The Sight Vol. 8

Vol 8, Issue 8, Nov 2012

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Abstract

Background: Presbyopia is an age-related impairment in amplitude of accommodation where the near point of the eye recede away ensuing diffi culty in near vision. Apart from the age, geographical variation, education, socio-economic status and profession have been occasionally associated with the age of presbyopia onset.

Objective: To investigate whether the ambient temperature, socioeconomic status and education infl uence the age of presbyopia onset.

Methods: This is a population based ecological study. The subjects of age range between 30 and 49 years were selected from two sites diff ering in ambient temperature (Site 1: Syangja, Nepal and Site 2: Andhra Pradesh, India). Subjects were stratifi ed based on age, occupation, socioeconomic status, and education level. Amplitude of accommodation was measured. Statistical analyses include paired t-test, chi-square test, multivariate analysis of variance and perasons’ correlation where appropriate.

Result: Mean age of onset of presbyopia among Site 1 and Site 2 populations were 42.3±0.46 and 38.7±0.58 years (p=<0.001) respectively. Mean of the amplitude of accommodation for age matched groups in two sites diff ered signifi cantly (p<0.001). No association was found between the age of onset of presbyopia and education level, profession, and socioeconomic status in both study populations. Occupation was moderately correlated with onset of functional presbyopia

in both sample groups.

Conclusion: Age is the major predictor of the accommodative amplitude. While ambient temperature has a considerable infl uence in dictating the age of onset, socioeconomic status, occupation, and education level are of little or no importance. Though the nature of near task infl uences functional presbyopia, this has nothing to do with the amplitude of accommodation and calculated presbyopia.

Key words: ambient temperature, functional presbyopia, calculated presbyopia, amplitude of accommodation.

Introduction

Accommodation is a physiological process that facilitates provision of clear vision for a range of viewing distances1. It is accomplished through a complex coordination of the neuromuscular action in the visual system. According to the Helmholtz theory2,3, during accommodation the ciliary muscle contracts releasing tension on zonules. The lens surfaces, mostly the anterior, become more curved thereby increasing the dioptric power of the crystalline lens. While focusing at distance, often called dis-accommodation, the ciliary muscle relaxes leading to increase in the diameter of the ciliary aperture. This imposes tension on the zonules causing the lens surface to become fl atter.

A young eye is capable of changing focus for a wide range of viewing distances with ease. With age, the crystalline lens becomes more resistant to shape change. As a result the amplitude of accommodation (AA) gradually reduces until it is completely abolished in the

Onset of Presbyopia: Eff ect of ambient temperature, socio-economic status,

profession and education level

Jit B Ale Magar, BOptom, PhDMoreton Eye Group, Brisbane, Australia

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Volume 8, Issue 8November, 2012

Original Article


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mid-sixties.1,4

Presbyopia is an age-related decline in near vision due to insuffi cient accommodation. Every human being living his or her 4th decade of life encounters this universal problem. The global presbyopic population is estimated to be more than 1.4 billion.5 Clinically, presbyopia may be categorized into two: fi rst, the functional presbyopia, which is subjective and onset is dependent on the customary working distance of an individual. Second, the calculated presbyopia which is the clinician estimated condition. This type solely depends on the AA a person can exert.

Variable results have been reported on the age of onset of functional and calculated presbyopia. A study in Hyderabad, India found that the presbyopia starts as early as 30 to 35 years in Indian population.6 Likewise, Dutta et al found that the mean age of onset of presbyopia in Indian population is 35.86 years.7 Rambo and colleagues found the mean age for onset of presbyopia to be 37.5 years in another study done in India.8 Based on the data presented by Duane and Donder, the mean age of onset of presbyopia is 44 years in European population4,9. This variation indicates the geographical and environmental infl uence for the onset of presbyopia. This characteristic was fi rst noticed by Weale10 who subsequently proposed that ambient temperature is the second major risk factor.

Though nutrition, environment, altitude, general health, socioeconomic status, race, income have also been occasionally quoted as contributing factors for the reduced AA and early onset of presbyopia6,7, Hunter and Shipp found no signifi cant association.11 This paper investigates the onset of presbyopia among the population of two diff erent geographical areas. Potential eff ect of other ambient temperature, education level, socio-economic status and profession is also studied.

Methods

Sample Size

Sample size was calculated using the following

formula;

n = (1)2

8(1.96 + 0.84)2 x (1.46)2

n = (d)2

8(1.96 + 0.84)2 x (SD)2 1.96 – constant for 95% confidence interval

Power of the study of 80% (1- )

SD - the standard deviation found in pilot study

d - is the precision (acceptable difference)

= 133.72 or 134 subjects

Considering the age as the strongest confounding factor, subjects were categorized in four age groups in fi ve years interval.

Group 1 – Age between 30 to 34 years


Group 3 – Age between 40 to 44 years and


Furthermore, subjects were categorized according to the socioeconomic status, income, education level and their profession. Likewise, results were matched for nature of the near tasks such as reading and writing, knitting, fi ne mechanics, scale reading, sewing and non-specifi c. Subjects having any previous intraocular surgeries (e.g. lens extraction), cataract, Aphakia/pseudophakia, active ocular pathology, known systemic diseases, best corrected distance visual acuity <6/9 (<20/30) and under medication for ocular or systemic diseases were excluded from the analysis.

The Study Sites

Two study sites were selected: one from Nepal (Site 1: Putali Bazar, Pokhara) and another from Andhra Pradesh India (Site 2: Nalgonda, Bibinagar). Brief description of each site is summarized in Table 1.

Maximum temperature recorded in individual day for Site 1 was 37.4ºC in May and in Site 2, it was 47º in June (year 2004). Minimum temperatures were 1ºC (Dec) and 8ºC (Dec) in Site 1 and 2, respectively, year (2003). Mean of the monthly maximum temperature was above 30º for 75% of the times in Site 2, whereas it was within 20ºC to 30ºC throughout the year in Site 1. Average minimum temperature was below 10ºC during winter in Site 1 and it was


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13.3ºC in Site 2.

Table 1: General geographical features of two study sites

Feature Site 1: Putali Bazar, Nepal Site 2: Bibinagar, India

LocationNearest CityElevationLatitudeLongitudeNumber of seasonsMonsoonTemperature

Average Max (SD)Average Min (SD)

Syangja District, Gandaki ZonePokhara (30 km)2000 meters from the sea level28.1º N81.4º EFourJune to September

25.25ºC (3.77)14.08ºC (4.8)

Nalagunda district, Andhra PradeshHyderabad (30 km)530 meters from the sea level17.70º N78.29 EFourJune to September

33.25ºC (4.11)19.75ºC (2.18)

Clinical Procedure

Comprehensive ocular examinations were carried out to ensure the normal ocular health by ophthalmologist or qualifi ed optometrist. Slit-lamp biomicroscopy and direct or monocular indirect ophthalmoscopy without mydriasis were performed.

Figure 1: Monthly average minimum and maximum temperature of two sites during the year 2003/2004 based on information published in established daily national newspapers. Temperatures are for nearest cities from the study sites: Pokhara and Hyderabad for Site 1 and Site 2 respectively.

Unaided, pinhole and best-corrected distance visual acuities were measured using self illuminated Snellen distance acuity chart placed at six meters in a suffi ciently illuminated room. Near vision with and without correction was obtained using N-notation near chart at variable customary distance depending on patient’s habitual working distance. Dry retinoscopy was performed using a streak retinoscope in minimally illuminated room to determine patient’s refractive status followed by monocular subjective refraction. Cycloplegic refraction was deferred because of logistic constrains. General health status was determined by thorough past and present medical history.

Although, push up method is commonly used to estimate AA (it overestimates the AA signifi cantly


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due to proximal magnifi cation (about 400%) coming into play12-14), in this study, the minus lens method was employed for its reliability and reproducibility.15 The subject was seated comfortably in a well-illuminated room. Fresh distance correction was inserted in a trial frame in front of the eye under test; the fellow eye being occluded. Near target (N8 sized optotype ‘E’) was presented. Minus lens was introduced in the trial frame and gradually increased in 0.25D step until the target became just blurred. The absolute value of minus lens required to sustain the fi rst blur was noted and added to 3.33 (dioptric value of 30cm working distance). The resultant value was recorded as monocular AA. Same procedure was repeated in the fellow eye. Binocular AA was determined by introducing minus lenses simultaneously in front of both eyes. For presbyopic subject who could not distinguish N8 target with distance correction on, a plus lense in 0.25D steps increment was added over the distance correction.14 The minimum plus lens required to resolve the N8 target was noted. This was subtracted from 3.33. The resultant power was recorded as AA.

Statistical analysis

Statistical software SPSS (version 17) was used. Paired student’s t-test was used to compare the means. Multivariate ANOVA was used to compare the means of three or more groups. Yates corrected Chi-square (χ2) was calculated to test association of non-parametric variables such as gender, socio-economic status and educational level. Pearson correlation (r2) was calculated to test the strength of relation between two variables wherever applicable. The level of signifi cance was set at 0.05.

Results

Demography

Total 146 subjects were enrolled in the study: 72 (49.32%) from Site 1 and 74 (50.68%) from Site 2. Overall, 46.58% subjects were male and 53.42% were female. Summary of age group and gender of the subjects are shown in Figure 2.

Frequency of illiterates in Site 1 and Site 2 were 11% and 38% respectively. Socio-economic status of low, lower middle and upper middle classes were 22.2%, 59.7% and 18.1%, respectively in Site 1and 47.3%, 43.2% and 9.5% respectively in Site 2. Occupation, socioeconomic status and level of education are illustrated in Figures 3, 4 and 5. Summary of the distribution of refractive status are given in Table 2.

Figure 2: Age group distribution of Study Subjects

Figure 3: Socio-Economic Status of Subjects

Figure 4: Education level of the study subjects


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Amplitude of Accommodation (AA)

As expected, monocular and binocular AA decreased with age. Statistically signifi cant negative correlations (r2 = –0.96 and –0.91 for Site 1 and Site 2 respectively) were observed between age and bilateral or unilateral AA (Figure 7).

Maximum hypeorpia was +2.0D in site 2 and +1.50D in Site 1. Similarly maximum myopic spherical equivalent was –4.50D, one in each Site. Distribution of the refractive status curve follows the normal distribution curve (Figure 6).

Mean AA in the age group 30 to 34 years in Site 1 (7.53 ± 1.01D) was signifi cantly higher (p = 0.000) compared to that for the Site 2 (5.41 ± 0.94D). Similarly, statistically signifi cant diff erences (p < 0.001 for all groups) occurred between the sites for other age groups (Tables 2 and 3). Male subjects had clinically greater AA in both sites but it was statistically

insignifi cant (p = 1.22).

No statistical diff erence occurred in binocular AA with occupation (p = 0.959 & 0.40 for Site 1 and 2 respectively) and neither did with socioeconomic status (p =0.0955 & 0.303 respectively). A weak positive correlation was observed between AA and occupation and socio-economic status (r2 = 0.021 and 0.161 for Site 1 & 2 respectively).

There was no signifi cant diff erence in means of binocular AA with the type of ametropia for any age group (p = > 0.123) except for emmetropic groups for age 45 to 49 years (Table 2). No signifi cant correlation was found between strength of ametropia and AA (r2 = <0.27 for any site and type of ametropia).Table 2: Means of Binocular Amplitude of accommodation

with age

Age Group

(Year)

Site 1 Site 2t-statistics

p -

value Mean ± SD Mean ± SD

30 - 34 7.53 ± 1.01 5.41 ± 0.94 6.43 (df = 33) 0.0000

35 - 39 6.03 ± 0.87 3.87 ± 0.88 6.34 (df = 29) 0.0000

40 - 44 4.52 ± 0.89 3.06 ± 0.66 6.39 (df = 36) 0.0000

45 - 49 3.75 ± 0.47 2.71 ± 0.46 6.59 (df = 33) 0.0000

Presbyopia

Calculated presbyopia was determined assuming the mean working distance of 34 cm (Site 1: 34.1 ± 3.31cm; Site 2: 34.0 ± 3.6cm; p = 0.17). Assuming one third AA in reserve is required for a comfortable near work, minimum 4.41D binocular AA is set as the limit of calculated presbyopia. In this study, the calculated presbyopia started as early as 34

Figure 5: Distribution of Occupation. (O-1: Housemaker, O-2: Student/Trainee, O-3: Retired, O-4: Unskilled worker/small farmer, O-5: Skilled worker/clerk/small business, O-6: Teacher/med.

Business/Offi cer, O-7: Manager/Executive)

Figure 6: Distribution of Refractive Status

Figure 7: Mean of Bilateral Amplitude of Accommodation with Age


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years in 25% of the population and 100% above the age of 41 years in Site 2. In site 1, it started as early as 40 years. Fifty percent of the subjects suff ered calculated presbyopia at the age 40 years and 100% above the age of 45 years Site 1. Mean ages of onset of calculated presbyopia were 42.09 + 1.65 years and 37.76 + 2.24 years in Sites 1 and 2 respectively. The diff erence is statistically signifi cant (p= 0.000). There was no signifi cant correlation between calculated presbyopia and socio-economic status (r2 = 0.161) and the occupation (r2 = 0.124) in both sites.

Table 3: Age group, binocular amplitude of accommodation and refractive status.

Age GroupSite 1 Site 2

t-statistics p-valueMean ± SD Mean ± SDEmmetropia

30 - 34 years 7.64 ± 1.16 5.83 ± 1.06 3.11 (df = 14) 0.008

35 - 39 years 6.32 ± 0.84 4.14 ± 1.00 4.89 (df = 15) 0.001

40 - 44 years 4.30 ± 0.84 3.08 ± 0.75 3.43 (df = 18) 0.003

45 - 49 years 3.64 ± 0.58 3.08 ± 0.50 1.53 (df = 7) 0.169Hyperopia

30 - 34 years 7.16 ± 0.65 4.81 ± 0.67 5.89 (df = 9) 0.001

35 - 39 years 5.88 ± 0.78 3.87 ± 0.71 4.47 (df = 9) 0.001

40 - 44 years 4.39 ± 0.84 3.08 ± 0.53 2.84 (df = 11) 0.016

45 - 49 years 3.58 ± 0.59 2.56 ± 0.41 3.94 (df = 13) 0.002Myopia

30 - 34 years 7.58 ± 0.12 5.33 ± 0.89 3.40 (df = 7) 0.011

35 - 39 years 5.08 ± 0.71 3.39 ± 0.66 3.25 (df = 5) 0.023

40 - 44 years 5.33 ± 0.87 3.19 ± 0.32 5.62 (df = 8) 0.001

45 - 49 years 3.87 ± 0.30 3.08 ± 0.24 3.93 (df = 7) 0.006

Mean age for the functional presbyopia in Site 1 was 42.31±1.33 years and in Site 2, it was 38.74±2.09 years. The diff erence is statistically signifi cant (p = 0.000). No signifi cant correlation was found between age of onset of functional presbyopia and socio-economic status in Site 1 (p > 0.192) and the result was almost identical for Site 2 (p > 0.936; (Tables 4 and 5). Presbyopia started as early as 40 years in Site 1 and 35 years in Site 2. 100% of the subjects in Site 1 suff ered near problem at the age of 44 years and above; this was 41 years and above in Site 2.

Table 4: Onset of Functional Presbyopia and Socio-economic Status

Socioeconomic Status Mean±SD t-value df p r2

Site 1 LowLow middleUpper Middle

43.2 ± 1.3342.1 ± 1.3242.4 ± 1.14

1.335 29 > 0.192 0.241

Site 2 LowLow middleUpper Middle

38.35 ± 2.2939.25 ± 1.7738.75 ± 2.06

0.0804 51 > 0.936 0.011

If the Site 2 is considered as an “exposed” group (exposed to high ambient temperature) and Site 1 as an “unexposed” group (low ambient temperature), the risk of developing calculated presbyopia in Site 2 is approximately 4 (RR = 3.78) times greater than among the Site 2 subjects (Yates corrected χ2 = 13.39, p < 0.001). The risk of functional presbyopia was 2.6 times higher


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among the site 2 subjects (Yates corrected χ2 = 7.01, p = 0.008). However, onset of functional presbyopia and nature of a near task had moderate positive correlation and were statistically signifi cant in the both the sites; Site 1: r2 = 0.66, p = 0.001 and Site 2: r2 = 0.51, p = 0.008. Similarly working distance had moderate positive correlation to the age of onset but did not diff er signifi cantly in both study sites.

Table 5: Age of onset of functional presbyopia with type of near task

Near Task

Site 1 Site 2

p-valuen

Mean ±

SDn

Mean ±

SD

Knitting/Sewing 1540.7 ±

0.2114

37.1 ±

0.46<0.0001

Reading/Writing 3542.5 ±

0.1431

39.3 ±

0.34<0.0001

Non-specifi c 1643.5 ±

0.1922

39.6 ±

0.45<0.0001

p – value

between groups<0.0014 0.0026

Discussion

The current study investigated association of factors such as geography and temperature, socioeconomic status and education level to the onset of presbyopia. A high negative correlation between age and AA is confi rmed. The AA among the population living in higher annual ambient temperature were signifi cantly lesser compared to those living in lower ambient temperature and so did the age of presbyopia onset. For 30 to 34 years of age, binocular mean amplitude of accommodation was 7.53D among the subjects of lower ambient temperature (Site1), which is similar to the value found by Duane (7.3D).16 Among the subjects of higher ambient temperature, (Site 2) it was 5.41, which concords with the other reports for Indian population.6,8

This study found comparatively earlier onset of functional presbyopia among the Site 2 subjects where mean age of presbyopia onset was 38.7 years, which is close to the result found by Rambo et al8 (37.5 years); however, it is higher than reported by Dutta et al

(35.8 years).7 In contrast, the age of onset of functional presbyopia among the subjects in Site 1 was 42.31 years, which is in between the age found in European population16 (44 years) and Indian population6-8.

Onset of the functional presbyopia was moderately correlated to the nature (r2=0.52 to p=0.66) and distance (r2=0.22 to 0.33, p=0.0617) of near task. The reason is obvious: fi ner the near work, the more the demand of accommodation; and the closer the working distance, the more the demand of accommodation. At the age of 40 years, only 33.3% subjects from site 1 (lower ambient temperature) had presbyopia; whereas, 92.3% subjects from Site 2 (higher ambient temperature), had near diffi culty. Similarly, 17 out of 36 (47%) had borderline or signifi cant calculated presbyopia at the age of 39 years among Site 2 subjects but none of the subjects from Site 1 had symptoms of presbyopia at this age. This study did not fi nd signifi cant association between onset of presbyopia and socioeconomic status (r2 = < 0.24, p = > 0.192), education level (r2 = < 0.154, p = > 0.523), gender (r2 = 0.128, p = > 0.87) and occupation (r2 = < 0.081, p = > 0.400). Similar result was reported by Hunter, and Shipp.8 No associations between refractive status and the onset of calculated (r2 = < 0.132) or functional presbyopia (r2 = 0.33) were established.

Conventionally, the onset of functional presbyopia is believed to start in earlier age among a hyperopic person compared to emmetropic and myopic individuals. But, this is theoretically incorrect for calculated presbyopia since there is no evidence suggesting that the hyperopia is a cause for reduced AA. However, for an uncorrected hyperopic eye, certain portion (equal to the hypermetropia) of exerted AA is used in compensating the refractive error. Obviously, a hyperopic eye has to accommodate more than an emmetropic or a myopic eye for the same near working distance. Hence, an uncorrected hyperopic person will become symptomatic to near work where a myopic or an emmetropic person of the same age may perform without


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diffi culty.

The biological reason for premature retardation of AA in higher temperature is still ill-understood. A study suggested that heat absorbed by the aqueous and the iris is transferred to the underlying crystalline lens, which causes denaturation of the lens protein.17 For many years, ultraviolet (UV) and infrared (IR) radiation has been suspected as a major factor in the degradation in the functional integrity of the crystalline lens.18 Laboratory studies demonstrated that exposure to UV portion of the spectrum leads to the changes that closely resemble aging process. UV ray is important contributor in the deleterious lenticular changes leading to the premature presbyopia. Stevens and Bergmanson17 reported laboratory scientifi cally credible evidences supporting this notion. Similarly infra-red portion of the spectrum has thermal eff ect which denatures cell protein causing a loss of function. Lens proteins, especially the alpha B (αB) crystallins, were found to be heat sensitive resulting in its structural deformation. In an experiment, Liang et al found that alpha crystallins of the lens undergo heat-induced aggregation on high temperature by its greater susceptibility of conformational change, becoming more unfolded.19 Magnitude of the UV ray increases as the equator approaches. This explains the earlier retardation in AA among the subjects of Site 2 which is closer to the equator compared to Site 1 (Latitude = 17.1ºN vs. 28.1ºN).

To conclude, apart from the age, ambient temperature also has considerable infl uence on amplitude of accommodation hence aff ects the age of onset and progression of the presbyopia. Exposure to higher ambient temperature causes a reduced AA resulting in the earlier onset of presbyopia. However, age of the onset of presbyopia is not aff ected by socioeconomic status, occupation, and education level. Nature of near task and the customary working distance almay determine the onset of functional presbyopia but these factors have no eff ect on amplitude of accommodation and calculated presbyopia.

References

1 Donders FC. On the Anomalies of Accommodation and refraction of the eye. The New Sydenham Society, London, 1864.

2 Helmholtz H. Treatise on Physiological Optics, English Language ed. New York: Dover, 1851.

3 Helmholtz H. Helmholtz's Treatise on Physiological Optics, Electronic Edition, 2001 ed. Menasha, WI: George Benta Publishing Co., 1924.

4 Donders F. Accommodation and refraction of eye. The New Society 1964: 204-215.

5 Holden BA, Fricke TR, Ho SM, Wong R, Schlenther G, Cronje S, Burnett A, Papas E, Naidoo KS, Frick KD. Global vision impairment due to uncorrected presbyopia. Arch Ophthalmol 2008; 126: 1731-1739.

6 Marella M. Amplitude of accommodation in Indian population. In. BSOptometry Project: BITS (Pilani), 2003.

7 Dutta D, Mahapatra R, Rao K. A study on the onset of presbyopia and its relationship with nutrition and socio-economic status. Orissa State Journal 2000: 19-21.

8 Rambo V, Sangal S. A study of the accommodation of the people in India. Am J Ophthalmol 1960; 49: 993-1004.

9 Duane A. Studies on monocular and binocular accommdaotion with their clinical implication. Am J Ophthalmol 1922; 1922: 865-877.

10 Weale R. Human ocular aging and ambient temperature. Br J Ophthalmol 1981; 65: 869-870.

11 Hunter Jr H, Shipp M. A study of racial diff erence in age at onset and progression of presbyopia. J Am Optom Assoc 1997; 68: 171-177.

12 Chen A, O'Leary J. Validity and repeatibility of the modifi ed push-up method for measuring amplitude of accommodation. Clin Exp optom 1998; 81: 63-71.

13 Lothringer L. Methods for measurement of amplitude of accommodation. In: http://www.emedicine.com/oph/topic724.htm ed, 2004.

14 Ostrin L, Glasser A. Accommodation measurement in a pre-presbyopic and presbyopic population. J Cataract Refract Surg 2004; 30: 1435-1444.


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15 Rosenfi eld M, Cohen S. Repetability of clinical measurement of the amplitude of accommodation. Ophthalmic Physiol Optic 1996; 16: 247-249.

16 Duane A. Normal values of the accommodation at all ages. J Am Med Ass 1912; 59: 4.

17 Stevens M, Bergmanson J. Does sunlight cause premature aging of the crystalline lens? J Am Optom

Ass 1989; 60: 660-663.

18 Goldman H. Radiation and eye. Arch Ophthalmol 1930; 125: 648-653.

19 Liang J, Sun T, Akhtar N. Heat-induced conformational changes of human lens recombinant alpha-A amd alpha-B crystallins. Mol Vision 2000; 2: 10-14.


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Abstract

A case of bilateral penetrating keratoplasty with left eye pseudophakia post blast injury was studied in 30 year old male. He was prescribed with aspheric rigid gas permeable contact lens which corrected his vision partially. He had optic atrophy in right eye and signifi cant corneal distortion, neovascularization and corneal scar in the left eye. Owing to visual impairment even with the RGP lens and complaint of poor near vision, he was prescribed spectacle microscope in the form of executive bifocal for the near vision task.

Key words: penetrating keratoplasty, contact lens, spectacle magnifi er

Introduction

Despite good graft clarity in penetrating keratoplasty (PK), patient may require contact lens for visual correction owing to irregular corneal astigmatism not readily correctable with spectacle alone.1,2,3 Rigid gas permeable (RGP) contact lens may be the correction of choice for good visual acuity. It corrects high degree of regular and irregular astigmatism, and has high oxygen permeability, minimal microbial keratitis, and neovascularization.4,5,6

RGP contact lens is a special indication in case of the scar between graft and host cornea.2,7

This case report highlights importance of both contact lens and low vision management in the patient after PK.

A case report

A case of bilateral penetrating keratoplasty with left eye pseudophakia was managed with a contact lens and spectacle magnifi er in 30 year old male. He had sustained blast

injury in both eyes 8 years back during maoist insurgency. His chief complaint was inadequate near vision with his present contact lens which he had worn only in left eye and had lost. He was a typist by profession. Other ocular and systemic history was within normal limit.

Unaided visual acuity was OD 2/60 OS 4/60. On refraction, visual acuity could be improved to 4/60 in right eye with -6.50/-3.00 080 and 6/60 in left eye with -6.00/-4.00 100. Duction as well as version extraocular motility was full in all the gazes. Lid examination revealed mild grade of meibomian gland dysfunction. Mild and diff use congestion was present in conjunctiva more in left eye than in right eye. An Opacifi cation was present between host and graft in both eyes (fi gure 1.A&B). In the left eye, neovascularization could be seen extending on to the centre of the donor cornea around 6 to 7 o’clock (Figure 1B). There was a central corneal opacity with superfi cial punctuate keratitis (SPK) around the opacity in the left eye. Bilateral anterior chamber was quite and normal in depth. Peripheral iridectomy was present at around 11 o’clock position in right eye. Pupil was inferonasally displaced, oblong and sluggish in reaction due to pupillary capture in left eye. Left eye was pseudophakic. Vitreous was transparent. Retinal examination revealed optic atrophy in right eye and normal in left eye.

Right eye topography read Sim K 43.69@162º & 40.90@72º with mean K 40.07@ 67º surface asymmetry index (SAI) 0.42 and surface regularity index (SRI) 0.95. Left eye topography read Sim K 42.97@142º & 39.25@52º with mean K 37.22@ 53º surface asymmetry index

Visual rehabilitation with Combined Contact

Lens and Bifocal Spectacle Magnifi er in a Case

Following Penetrating KeratoplastyShrestha, Mr. Gauri Shankar, (M.Optom, FIACLE Lecturer)

Chaudhary, Dr. Meenu, (MD Lecturer)B.P. Koirala Lions Centre for Ophthalmic Studies,

Institute of Medicine, Tribhuvan University

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(SAI) 3.85 and surface regularity index (SRI) 1.79 (Figure 2).

The following parameter of aspheric RGP lens provided acceptable fi tting characteristics (Figure 1) that was prescribed to the patient having oxygen permeability of 90Dk two weeks after treatment for meibomitis and SPK (Figure 1C&D).

Eye Base curve Total diameter Optic zone diameter power VA

OD 7.60mm 9.2mm 7.40mm -6.00DS 6/60

OS 7.40mm 9.2mm 7.80mm -3.50DS 6/24

The acceptable fi tting characteristics was defi ned by the best possible alignment fi t to minimize bearing which was guided by lens movement, lens centration, fl uorescein dye tear pattern, and the maintenance of corneal surface integrity.

Bifocal spectacle microscope was prescribed on top of contact lens as his current level of near vision was found inadequate for reading in computer screen and news paper. He didn’t have problem in writing, mobility, glare and light adaptation. He was satisfi ed with current level of distance vision. However he has been advised to use monocular telescope of 3X in left eye for spotting at distance. His near vision was found OD 4M at 12cm over contact lens and OS 2.0M at 30 cm with contact lens and +3.00DS addition. His target acuity for reading was set at 0.8M for equivalent viewing distance of 15cm. His target acuity for viewing a key board was set at 1.6M for equivalent viewing distance of 25cm. Executive bifocal spectacle with segment top at 1mm above lower lid margin was prescribed for near vision having +5.0DS above and +8.0D below segment top for left eye. He was further advised to magnify the font size in the screen during typing the text. He was also advised to keep magnifi ed format of applications in computer screen.

Discussion

Irregular corneal astigmatism and anisometropia remain the optical challenge following PK. 20% to 60% post-PK patient’s benefi t optically from CL wear.2,8 Apart from RGP contact lens, the other contact lens alternatives for the post-keratoplasty patient include soft lenses, piggyback lenses and scleral lenses. Post-PK eyes that exhibit high refractive errors but minimal astigmatism occasionally benefi ts from hydrogel CLs. However, they can cause hypoxia and secondary cornea neovascularization, which increases the risk of graft rejection.1,9

Piggyback contact lenses can be used where adequate centration cannot be achieved with an RGP contact lens however the reduced oxygen transmissibility of the piggyback lens system


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increases the potential for graft failure. Pre-formed scleral lenses made in an RGP material are another option for the post-keratoplasty patient. Disadvantage of preformed scleral lens is diffi culty in fi tting and advantage is good centration on the eye.10 These type of lenses are not available in our clinical set up. Neovascularization in the graft in left cornea suggests a state of compromization with previous contact lens indicating high chance of graft rejection. This fi nding warrants requirement of both optimal fi tting characteristics and high oxygen permeability of the material.

The nature of the graft determines type of contact lens management. It may include diameter of the graft, centration of the graft, resultant corneal toricity and topographical relationship between the host cornea and donor cornea. If the graft is too small, the edge of the graft may be within the pupillary zone, leading to glare and other visual symptoms. If the graft is large, the edge of the graft will be close to the limbal vasculature, increasing the chances of blood vessel infi ltration into the donor cornea and subsequent graft failure.9 Graft zones of greater than 9mm or more will often allow the practitioner to fi t a small diameter RGP lens that position within the region of the graft. However, the graft size in our case was approximately 8.5mm suggesting that the total diameter of the CL usually should be large to improve the stability, centration, and patient tolerance. 1,9 In our case, selected diameter of the lens was 9.2mm which was slightly larger (0.7mm) than the total graft diameter to ascertain adequate edge clearance of lens for tear exchange and to release heavy bearing on the graft. Corneal topography in our case showed normal elevation in spite of signifi cant corneal astigmatism and distortion. Corneal graft was well centered in both eyes. However, optic atrophy in right eye hinders the benefi t of contact lens improving the optical clarity. Similarly, eccentric location of pupil in the left eye may cause visual symptoms such as fl are and monocular diplopia in spite of having well

centered contact lens. A possible solution was to design lens with either a large or decentered back optic zone diameter of lens or make fi tting of lens low riding. However low riding lens decreases the level of comfort associated with the wearing of the lens. In our case, we determined to select a large diameter lens so that pupil coverage can be ascertained.

Fortunately corneal astigmatism in our case was within 3 to 4 diopters though corneal distortion was seen remarkably. Corneal astigmatism was found almost similar to the refractive astigmatism indicating possibility of spherical RGP to correct corneal astigmatism as well as distortion.9 Mostly RGP contact lens improves visual acuity up to 6/12 in PK.7 Of interest, he did not achieve normal vision with RGPs suggesting that RGP didn’t completely neutralize corneal distortion in left eye and there was optic atrophy in right eye. To meet the patient’s visual demand for reading and typing, an extra optical consideration had to be considered to achieve this goal. Being that reason, he was prescribed spectacle microscope in the form of executive bifocal. Both the optical portion in bifocal will be used purely for near vision. Non-optical accessory tools also have to be suggested to ease patients near work depending upon the task one has to perform. At last, this study suggests that contact lens alone may not be suffi cient in visual rehabilitation after penetrating keratoplasty and optical aids may be necessary for better visual rehabilitation.

References

1. Ho SK, Andaya L, Weissman BA. Complexity of contact lens fi tting following penetrating keratoplasty. Int Contact Lens Clin 1999;26:163–7.

2. Smiddy WE, Hamburg TR, Kracher GP, et al. Visual correction following penetrating keratoplasty. Ophthalmic Surg 1992;23:90–93.

3. Mannis MJ, Zadnik K. Refracting the corneal graft. Surv Ophthalmol 1990;34:436–40.

4. Cheng KH, Leung SL, Hoekman HW, et al. Incidence of contact-lens associated microbial keratitis and its related morbidity. Lancet 1999;354:181–5.


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5. Dart JK, Stapleton F, Minassian D. Contact lenses and other risk factors in microbial keratitis. Lancet 1991;338:650–3.

6. Chan WK, Weissman BA. Corneal pannus associated with contact lens wear. Am J Ophthalmol 1996;121:540–6.

7. Wietharn BE, Driebe WT Jr. Fitting contact lenses for visual rehabilitation after penetrating keratoplasty. Eye Contact Lens 2004;30:31–3.

8. Silbiger JS, Cohen EJ, Laibson PR: The rate of visual recovery after penetrating keratoplasty for keratoconus. CLAO J 1996; 22:266—269.

9. Lindsay R. Post keratoplasty contact lens management. Clin Exp Optom 1995; 78:223-226.nm

10. Tan DTH, Pullum KW, Buckley RJ. Medical applications of scleral contact lenses: 2. gaspermeable scleral contact lenses. Cornea 1995; 14: 130-137.

Figure 1. Bilateral penetrating keratoplasty and contact lens fi tting.

Figure 2. Bilateral corneal topography with placido disc

Corresponding address

Gauri Shankar Shrestha, M.Optom, FIACLELecturerB.P. Koirala Lions Centre for Ophthalmic Stud-ies,Tribhuvan University, Institute of Medicine,Maharajgunj, KathmanduP. O. Box: 8750Email: [email protected]


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Objectives: Low vision devices reduce the consequences of the visual impairment in life. The aim of this study was to fi nd out the prevalence and the major low vision devices prescribed in pediatric low vision children in low vision clinic of Nepal Eye Hospital (NEH).

Methods: It is a retrospective and cross sectional study. All the report fi les of the children who visited low vision clinic of NEH at the fi rst time from 1st May 2009 to 31st October 2011 (30 months) were reviewed. Their age, sex, best corrected visual acuity, refractive status and the prescribed low vision devices were analyzed.

Results: In this period, 69 children attended low vision clinic of NEH. Mean age of the children was 9.87 years. 42% of patients had best corrected visual acuity of 3/60 or worse in the better seeing eye. Nystagmus was found to be the most common cause of visual impairment which was found in 59.42% (41) children. Two thirds of children had multiple causes of low vision. General glasses were prescribed for 77% of children. Low vision devices were prescribed for 28% of children and telescope was prescribed for 68% of them. Hand held magnifi er was prescribed for 5 and stand magnifi er was prescribed for a single patient.

Conclusion: General glasses improve the visual acuity of many low vision children. Prescription of low vision devices was very low. Telescope was the most common low vision device prescribed.

Key words: Children, Low vision devices, Telescope.

Introduction

A person is said to be with low vision if the reduction in visual acuity or visual fi eld hinders the daily living activities and his professional

Low Vision Devices Prescribed in Low Vision Children of Nepal.

work. WHO defi nes low vision as the best corrected visual acuity of 6/18 to 3/60 in the better seeing eye. There are 161 million people with low vision in the world [Pascolini 2002]. In Nepal, about 1.85% of the total population is estimated with low vision [Brilliant 1985]. However, no data are available about the prevalence of low vision in Nepalese children.

Low vision is responsible for a high proportion of social care service use and results in important reductions in functional status. Low vision devices are the simplest way of reducing the consequences of impaired vision. Low vision devices can improve the quality of life of visually impaired children. The prescribing of LVD depends on the individual: it is not possible to anticipate the optical power of the LVD that a patient will need simply from looking at their diagnosis and measuring their VA because there are so many diff erent requirement depending on their age and visual demand [Gajdosova et al, 2010]. Reading rate increases signifi cantly with improved near visual acuity in school children by low vision devices [Sharma MK et al, 2010].

No studies have been done about need of low vision devices among children in Nepal. This study was designed to investigate the proportion of low vision children needing low vision devices in Nepal. This study also evaluated the major low vision devices prescribed and their magnifi cation. It will help to understand low vision practitioners to use the low vision devices eff ectively.

Methods and methodology

It was retrospective study conducted in the low vision department of Nepal Eye Hospital, Kathmandu, Nepal. All the patients who fi rst time visited the clinic with age 15 years or younger and best corrected visual acuity (BCVA) equal or less than 6/18 in the better

Kishor SapkotaOptometrist, Nepal Eye Hospital

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eye were included. Patients older than 15 years were excluded.

All the patients were referred cases from the primary eye care center or other departments of the hospital. Visual acuity was measured with Bailey-Lovie or Snellen chart in each patient. Cycloplegic refraction was performed with instillation of cyclopentolate 1% followed by tropicamide 1% in each eye. Refraction was done by a senior optometrist while other ocular ophthalmic examination was done by consultant ophthalmologist trained in low vision. A cause of low vision was diagnosed after the diff erent investigations. Besides the general refractive error correction, near and/or distance visual acuity of each patients was tested with the low vision devices like high powered glasses, spectacle magnifi ers, hand held magnifi ers, stand magnifi ers and telescopes with diff erent focal strength. Low vision devices were prescribed depending upon the performance of the patients with the device and the need.

Data were analyzed by SPSS 13 software and t test, X2 test were used to determine the association between diff erent variables. P value of less than 0.05 was considered as statistically signifi cant.

Results:

In the period of 30 months, 31,315 children were examined in Nepal Eye Hospital. Out of them 69 (0.2%) children were referred to low vision clinic of NEH. Mean age of the children was 9.87±3.316 years with range 4 to 15 years. The median age of the children was 10 years. Fifty fi ve percent were male and 45% were female. Boys were younger than girls but there was not signifi cant diff erence in the age between two genders (Independent Sample T-Test, t = -0.438, df = 67, p = 0.662).

Table 1 shows the best corrected visual acuity (BCVA) in the better eye. Visual acuity of 6/36 and 6/60 were found in the highest number of patients in their better eyes. 25 (36%) patients had visual acuity worse than 3/60 in their better eyes.

BCVA Frequency Percentage6/24 7 10.16/30 5 7.36/36 11 15.96/60 11 15.95/60 3 4.44/60 3 4.43/60 4 5.82/60 9 13.01/60 6 8.7CF 7 10.1PL 3 4.4Total 69 100

Overall, 52 (75%) patients were improved by general glasses in at least one eye. 6 myopic, 13 hyperopic and remaining 33 had astigmatism in the better seeing eye. The mean refractive error (spherical equivalent) was +1.5D ± 5.9D with range -18.00D to + 14.00D. 22 had mild refractive error, 13 had moderate refractive error and 17 had high refractive error in the better eye.

Table shows the causes of visual impaired in low vision children. Nystagmus was found as the most common etiology of the visual impairment. So, we statistically analyze the association of nystagmus with sexes. Nystagmus was not associated with the sex (Chi-Square test, X2 = 0.82, P = 0.775).

Causes of VI Frequency PercentageNystagmus 41 59.42%

High ref error 17

Amblyopia 16

Cataract 12Microophthalmus 9

Coloboma 9

Squint 8RP 6Albinism 5

Optic attrophy 3

Macular scar/ hole 3

Others 9Unknown cause 2Total 140

Majority of the patients had multiple causes of visual impairment. The mean number of


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causes was 2±0.97. Two had unknown cause, 22 had single cause, 23 had two causes, 18 had three causes and 4 had four causes behind the visual impairment.

General glasses were prescribed for 52 (75%) patients. Low vision devices were prescribed for 19 (27.5%) children. Telescope was prescribed for 13 (68%), hand held magnifi er for 5 (26%) and stand magnifi er for one patient. The magnifi cation of the telescope was 3X in 2 cases while 4X in 11 cases. Similarly, 2X power hand held magnifi er was prescribed for 4 and 3X for one patients in hand held magnifi er prescribing group. The only stand magnifi er prescribed was 3X power.

Since the telescope was the most frequently prescribed low vision devices, we investigated any association on the age and gender to prescribing of telescope. There was no association between the age and telescope prescribing (Independent Sample T-Test, t = 0.899, df = 67, p = 0.372). Similarly, there was not signifi cant relationship between the gender and the telescope prescribing (Chi-Square test, X2 = 0.515, P = 0.473).

Discussion

Only 0.2% of the total patients were referred to the low vision rehabilitation clinic in NEH and more than one third of them had BCVA worse than 3/60 in the better seeing eye. This is lower than the prevalence of low vision in Nepal [Brilliant 1985]. This shows that referral system in NEH has some lacking. One of the possible factors may be the misunderstanding in ophthalmologist in low vision rehabilitation. Another reason may be the fact that many children having low vision do not visit the hospital or the insuffi cient vision screening programs. This highlights the need of proper referral system of low vision patients and more vision screening programs.

Nystagmus was found to be the most common cause of visual impairment. It was not associated with the gender. Majority of the children had multiple causes.

Vision was found improved in 75% of children

by general spectacles. This shows that proper refraction is necessary for the low vision patients.

Low vision devices were prescribed in 27.5% of low vision children. This is lower in comparison to other study. 65% of the low vision children were prescribed low vision devices in a study done by Gajdosova and co-workers [Gajdosova et al, 2010]. Less than one third low vision children were prescribed low vision device in our study. This may be due to the fact that only few types of low vision devices are available in Nepal. Another factor may be the cost of low vision devices. Majority of the children with low vision are of lower socio-economic status who cannot aff ord the expensive low vision devices.

In our study, telescope was found to be the most frequently prescribed low vision devices. Telescope was prescribed in 68% children, hand held magnifi er in 26% and stand magnifi er in 6% cases. In contrary to our fi ndings, magnifi ers were prescribed in 44% cases, hyperoculars or high aid in 12% and telescope in 38% cases in the study of Gajdosova study [Gajdosova et al, 2010].

This study could not determine the effi cacy and the abandonment of the low vision devices. Dougherty and co-workers [Dougherty et al, 2011] did a study on the abandonment of low-vision devices in an outpatient population. They found that, of the 119 prescribed devices, 19% had not been used within the previous 3 months. Patients with visual fi eld loss may be more likely to abandon prescribed devices. Proper training is necessary for the eff ective uses of low vision devices. However, it was found that additional training is not necessary for the simple low vision devices [Pearce et al, 2011].

References

Gajdosova E, Kukurova E, Gerinec A. [Improvement in the outcome of visual impairment using low vision aids in children]. Cesk Slov Oftalmol. 2010;66:266-72.

Pearce E, Crossland MD, Rubin GS. The effi cacy


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of low vision device training in a hospital-based low vision clinic. Br J Ophthalmol. 2011;95:105-8.

Dougherty BE, Kehler KB, Jamara R, Patterson N, Valenti D, Vera-Diaz FA. Abandonment of low-vision devices in an outpatient population. Optom Vis Sci. 2011;88:1283-7.

Pascolini D, Mariotti SP, Pokharel GP, et al. Global update of available data on visual impairment: a compilation of population-based prevalence studies. Ophthalmic Epidemiol 2002;11:67–115.

Brilliant RL, Pokhrel RP, Grasset NC, et al. Bulletin of the World Health Organization 1985;63:375-386.

Sharma MK, Thapa H, Paudyal B, Adhikar RK, Dhakwa K. A profi le of low vision among the blind school students in Lumbini Zone of Nepal. Nepal J Ophthalmol. 2010;2(4):127-31.

SSudrishti EEye ClinicKings way, Kathmandu

Tel: 014228531

General Eye Examination

(including evaluation of Glaucoma)

Pediatric Eye Examination

(Including Squint evaluation and Vision therapy)

Contact lens service

(Contact lens trial, counseling & dispensing by Qualified Optometrist)

Pharmacy

(Glaucoma and other medicines)

Appointment time: 2PM onwards (Sunday to Friday)

Tel: 014228531

AAvvailable services

Consultation time: 4PM to 8PM


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Abstract

Introduction:

By scientifi c report of free eye screening camp in a rural community, we can understand a particular type of community in a better way and plan for future camps in such communities in a better way. It can also help us to plan for eye care services in such communities.

Methods

One day free eye camp was conducted in Tistung VDC; a rural hilly village of central Nepal. Visual acuity was assessed using Snellen chart. Anterior segment evaluation was done with the help of torch light. Posterior segment evaluation was done with ophthalmoscope. Streak-retinoscopy, subjective refraction, Schirmer test I&II, Syringing and Perkin’s tonometry were performed in required cases. Data on age, gender, ethnicity, religion and major diagnoses were recorded and analysed using SPSS-17 software.

Results

68% of the people presenting to the free eye camp had ocular morbidity who were not having any treatment. Mean age of presentation was 48.60 +/- 23.39. 12.92% were pediatric population and 40.62% were elderly. 59.1 % of the total subjects screened were female. Unlike the caste composition of Nepal, a relatively larger percentage of so called lower caste people (20.92%) were screened in the camp. Among 221 cases with ocular morbidity, 40.27% had dry eyes, 30.32% needed refractive correction and 26.24% had visually signifi cant cataract. Among the cataract cases, 62.07% had bilateral visually signifi cant cataract.

Conclusion

Free eye screening camps are important for screening and treating ocular morbidity in rural communities. Larger group of passive population, female population and so called lower caste population are extremely benefi tted from such camps.

Key words: Cataract, Morbidity, Nepal, Refractive Errors, Rural Population

Introduction:

Rural population comprises 85% of the total population of Nepal. Eye screening camps are frequently conducted by diff erent organizations in diff erent rural communities but their reports are rarely presented in a scientifi c way. If it could be done, a particular type of community would be understood in a better way. It can help to plan for preventive and curative eye care services in such communities1 and eye camps can be conducted in a more systematic way in the future.

Methodology:

One day free eye camp was conducted in Tistung VDC; a rural hilly village of central Nepal. Health post was quite far from the site of the screening camp. Awareness to the local people about the eye screening camp was made through pamphlets and miking. Verbal consent was taken from the subjects for inclusion in the study. Visual acuity was assessed using Snellen chart. Anterior segment evaluation was done with the help of torch light. Posterior segment evaluation was done with ophthalmoscope. Streak-retinoscopy, subjective refraction, Schirmer test I&II, Syringing and Perkin’s tonometry

Pattern of ocular morbidity in a rural community of Nepal

Himal Kandel,1 Safal Khanal,2 Amrit Pokhrel,2 Dr. Subash Bhatta3

1 Optometrist, Eye Care Pvt Ltd, Orchid Magu, Male’ 20262, Republic of Maldives2 Optometry Student, Institute of Medicine, Trihuvan University, Kathmandu, Nepal3 Ophthalmologist, Institute of Medicine, Trihuvan University, Kathmandu, Nepal

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were performed in required cases. Data on age, gender, ethnicity, religion and major diagnosis were recorded and analysed using SPSS-17 software.

Visually signifi cant cataract was defi ned by any, best-corrected visual acuity less than 20/40, cataract as the primary cause of vision impairment, and self-reported vision of fair or worse.2

Results:

A total of 325 subjects were screened for ocular morbidity and treated or referred to higher centres when required. Mean age of presentation was 48.60 +/- 23.39. 12.92% were pediatric population and 40.62% were elderly. 59.1 % of the total subjects screened were female. 20.92% of the cases were so called low caste people.

68% of the people presenting to us had ocular morbidity who were not having any treatment. Among 221 cases with ocular morbidity, 40.27% had dry eyes, 30.32% needed refractive correction and 26.24% had visually signifi cant cataract. (Figure 1) Among the cataract cases, 62.07% had bilateral visually signifi cant cataract.

Discussion:

The present study was carried out to fi nd out the pattern of ocular morbidity in a rural community of hilly part of Nepal.

Eye screening camps are important not only for screening the pattern of ocular morbidity but rather more important as eye-health care and people also consider it as a health care service. Larger group of passive population (53.54%) were benefi tted from the camp.

In the male dominated society, male population has better reach to eye care centers which are located quite far away from their residence areas. So, larger percentage of female are expected to come with ocular problems. In our study, most of the cases (59.1 %) were female.

Most of the subjects were Hindus followed by Buddhists and Christians respectively.

However, no signifi cant diff erence in the pattern of morbidity was found among them.

Unlike the caste composition of Nepal3, a relatively larger percentage of so called lower caste people (20.92%) were screened in the camp. This could imply that so called higher caste people who are comparatively more privileged have better reach to the eye care centres and the former wait for free camps for eye camp for eye care. However, we can’t generalize it as we are unaware of the caste composition of the community.

Among the dry eye cases, surface disorder dry eye was quite common due to pingueculae and pteregia. Most of the dry eye cases were female. People used fi rewood as fuel for cooking. Thus female were mainly exposed to the dust and smoke in the kitchen which might have been its reason.

Most of the people were unaware of refractive errors. People should be educated about the signs and symptoms of refractive errors.

Conclusion:

Free eye screening camps are important for screening and treating ocular morbidity in rural communities. Larger group of passive population, female population and so called lower caste population are extremely benefi tted from such camps.

References:

1. Gupta M, Gupta BP, Chauhan A, Bhardwaj A. Ocular morbidity prevalence among school children in Shimla, Himachal, North India. Indian J Ophthalmol. 2009;57:133–8.

2. Richter GM, Chung J, Azen SP, Varma R; Los Angeles Latino Eye Study Group. Prevalence of visually signifi cant cataract and factors associated with unmet need for cataract surgery: Los Angeles Latino Eye Study. Ophthalmology. 2009;116:2327-35.

3. CBS, 2001 census, Kathmandu Retrieved from http://www.cbs.gov.np/Population/Monograph/Chapter%2003%20%20Social%20Composition%20of%20the%20Population.pdf

Figure legend:Figure 1 : Pattern of ocular morbidityCorrespondence:Himal Kandel, Optometrist, Eye Care Pvt Ltd. Republic of

Maldives. [email protected], [email protected]


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Profi le of Binocular Visual status of Pediatric Patients Presenting with

complaints of Asthenopia

Arun Prasad DhunganaOptometrist, RLGEHF

Abstract

AIM: To determine the accommodative amplitude, fusional vergence, vergence status and refractive status of pediatric patients presenting with symptoms of Asthenopia.

Method: Total 820 pediatric patients with complaints of asthenopia were enrolled in the study. VA assessment, slit lamp biomicroscopy, retinoscopy and binocular vision assessment were done. Patients who required glasses were prescribed with glasses. Patients who needed exercises on Synoptophore were called for follow up and those requiring pencil-push up exercise, Hart chart rock exercises and other vision therapy were advised to do at home.

Results: Total 820 subjects were enrolled in the study. Among them, 51.85% were female and 48.15% were male. Most common age group presenting with symptoms of asthenopia at the OPD was of age group 11-16 yrs. The most common binocular disorder was fusional insuffi ciency.

Conclusion: Asthenopia was found to be related to fusional vergence defi ciency, accommodative and convergence insuffi ciency and refractive error. It can be concluded that factors of asthenopia, whether muscular or refractive seems to give rise to symptoms and cannot be neglected since it can have direct impact on overall physical and academic development of the children.

Keywords: Asthenopia, convergence, binocular disorders

Introduction:

Asthenopia is a term used to describe a

sense of strain and weakness or ocular fatigue set up by the use of the eyes (a=not, sthenos=strength, ops=vision) (Atencio 1996, palmer 1993). It is a term used to describe diff erent symptoms associated with the use of the eyes such as pain, blurred vision, diplopia, focusing problem, reading problem, eyestrain, tiredness and headaches. It is a common presenting complaint among patients with accommodation and convergence insuffi ciency, refractive error and intermittent strabismus.

It is most often reported in association with near vision. Children with asthenopia complain of such symptoms particularly when reading and writing. It is often divided into two main categories: refractive including refractive errors and anisometropia and muscular comprising strabisimus and convergence insuffi ciency. Symptoms of asthenopia are becoming more common in modern society where near work at computers required sustained fi xation often for hours, at the same visual distance, which puts a strain on the system for near vision.

Among school children, recent studies have reported a prevalence of asthenopia in 15.2% in 6 year old children (IP et al 2006) and 34% in school children 6-10 yrs of age (Sterner et al 2006).

Methods and Methodology

This was a hospital based and descriptive study. Children of age group 6-16 yrs presenting with symptoms of asthenopia at the OPD of Ram Lal Golchha eye hospital

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foundation were included with verbal consent of the guardians .Patients with any ocular or systemic pathologies were excluded from the study

General ocular and medical history was taken. Uncorrected visual acuity for distance was measured with Snellen chart at six meters. A complete ophthalmic examination was done including slit lamp examination and ophthalmoloscopy. Cover test, prism cover test were done for near and distance at 40 centimeters and 6mrters respectively. Positive fusional vergence was measured with base out prism at near and distance.

Normal range for near was considered as 9/19/10 prism dioptres (blur/break/recovery) and 17/21/11 prism dioptres (blur/break/recovery) for distance. Prism cover test was used to assess the amount of deviation. Near point of convergence was measured with RAF rule. Normal range of convergence was set at 6-9 cm from the eyes. Near point of 12 cm was denoted mild convergence insuffi ciency, 13-18 cm as moderate insuffi ciency and 19 cm and more as marked convergence insuffi ciency. Near point of accommodation was measured with RAF rule with N6 target. Normal accommodation was set at 6-9 cm, mild accommodative defi cit was defi ned at a near point of 10-15 cm, moderate defi cit at 16-20 cm and marked defi cit at more than 20 cm. Retinoscopy and subjective refraction was done. Dynamic retinoscopy and cyclo refraction was done whenever required. Exophoria was defi ned as ≥ 4 prism dioptres at distance and ≥ 6 prism diopters at near. Esophoria was defi ned as ≥ 2 prism dioptress at distance and ≥ 4 prism diopters at near.

Result

Total 820 patients who presented to the OPD with complaints of asthenopia were included in the study. Maximum children were of age group 13-16 years. Male comprised of 48.15% and female comprised of 51.85%.

Table 1: Pattern of refractive error on asthenopic children

Type of Refractive Error Percentage

Simple Hyperopia 20%Simple Hyperopic Astigmatism 9%Compound Hyperopic Astigmatism 6%Simple Myopic Astigmatism 7%

Compound Myopic Astigmatism 5%Myopia 11%Mixed astigmatism 4%Total 61%

Fig 1: Distribution of patients with their chief complaints

Table 2: Distribution of Binocular Disorder

Fusional Insuffi ciency 32%

Conv. Insuffi ciency 28%Conv. + Fusional Insuffi ciency 16%Accommodative Disorder 19%Accom + Conv + Fusion 5%Total 100%

Table 3: Prevalence of the type of accommodative dysfunction

Degree of accommodative dysfunction

Prevalence

Insuffi ciency 80%Spasm 4%Infacility 9%Fatigue 7%Total 100%

Table 4: Type of Deviation

Type of deviation PercentageOrthophoria 84.96%Exophoria 11.04%Esophoria 2.20%Heterotopia 1.80%Total 100.00%


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Discussion

We found that the refractive error and binocular disorder was associated with asthenopia in many children. Convergence insuffi ciency has been reported to be a common binocular disorder in children (Raise et al 1987) but in our study, fusional insuffi ciency was the commonest binocular disorder.

Similar to the study done by Abdis et al (84%) most common accommodate disorder was accommodative insuffi ciency (80%).

Conclusion

Asthenopia was found to be related to defi ciency of fusional vergence system, accommodative

disorder, vergence dysfunction and refractive error. So orthoptic evaluation is very important in case of pediatric patients complaining of asthenopia.

References

1. Atencio R. Eyestrain: the number one complaint of computer user. Computer in libararies 1996; 16:40-44

2. Rouse MW. Management of Binocular anomalies: Effi cacy of vision therapy in the treatment of accommodative defi ciencies. Am J Optom Physiol opt. 1987; 64:421-429

3. Abdi S, Rydberg A. Asthenopia in school children, orthoptic and ophthalmological fi nding and treatment. Documenta ophthallmologica, 2005; 111, 65-72

Proprietor: Dr. Sanjeev MishraContact: 984122738

Address: Tinkune, Subidhanagar, KTM


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Background: Optometry program in Nepal was started by Institute of Medicine in 1998 in collaboration with the University of Auckland, New Zealand. It is the only one institution in the country providing Optometry education for the last 14 years. Being a new profession, in many countries it is still in the growing phase and people are still unaware of the services

provided by various eye care professionals. Purpose: To determine knowledge and opin-ions of medical students about the diff erent kinds of eye-care providers and the services

they provideMethod: A full-page survey was adminis-tered to 106 medical students in third phase at Maharajgunj Medical Campus, Institute of Medicine, Kathmandu. Students were asked to respond to questions that tested their knowl-edge of diff erences among ophthalmologists, optometrists and opticians in an open phrase and a multiple-choice format. Questions con-centrated on the diff erences in training and qualifi cation in diagnosing and treating vari-

ous eye conditions.

Result: Among the 106 medical students of mean age 23+1.24 years (21 years to 26 years), 79 (74.5%) students had a history of eye check-up , among them 22(27.8%) had been evalu-ated by ophthalmologists, 26(32.9%) by op-tometrists and remaining 31(39.2%)by both ophthalmologists and optometrists. For the 28 (26.4%) students using spectacle correction, 15 (53.6%) were prescribed by optometrists, 10 (35.7%) by ophthalmologist and 3(10.7%)

by both of them. Most of the medical students when asked in an open response format, recognized that there is a distinction between ophthalmolo-gists and optometrists, but only 85(80.18%) attempted to describe the diff erence. Of this

group, 39 (45.9%) correctly described the dif-ference between the two specialties using the

following criteria:1. Lack of medical school and surgical

training2. Primary focus of education on optics of the eyes, examination of eyes and on recog-

nizing diseases in the eye

Furthermore, 55 (51.8%) of those surveyed thought that Ophthalmologists are not trained to prescribe glasses and contact lens and 35 (33%) thought that Optometrists can-not prescribe medications. When asked about surgical training, 17 (16%) said they did not know who was trained to perform Laser Re-fractive Surgery. 15 (14.1%) thought that both Ophthalmologists and Optometrists can per-form Laser Refractive Surgery. Only 52 (49.0%) thought that both Ophthalmologists and Op-tometrists can perform post-operative care after Laser Refractive Surgery and other 26 (24.5%) were not sure. On question regarding who can treat glaucoma, cataracts and macu-lar degeneration with surgery – 12 (11.3%) of the respondents answered that they did not

know. Conclusion: There is considerable uncertainty even among medical students, with regard to the diff erences among eye care professionals

and services they provide.

Author Correspondence

Sudan PuriB Optometry fi nal year

Maharajgunj Medical CampusMaharajgunj, Kathmandu

E-mail: [email protected]

Does uncertainty exist among Medical Students Regarding the Defi nitions of

Ophthalmology and Optometry?Sudan Puri

B Optometry fi nal year

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Original Article


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Optometrists are primary contact eye care professionals, who can manage majority of eye problems among patients seeking eye care services at any level of health care delivery. In developed countries more than 70% of the eye care is provided by optometrists. World Council of Optometry defi nes optometry as an independent profession but it is being realized by optometrists in developed countries only. The number of optometrists produced each year being large and their development of professional career which mostly begins as a private practitioner has helped them become an independent professional. Co-management of cases by diff erent health professionals and a clear demarcation of working areas have eased the patients in choosing their clinician as well as the professionals in setting up their own working arena.

In Nepal, comparing other parts of the world, optometry is a new profession. We have several eye health professionals with overlapped working areas and lack a clear health policy to delineate job responsibilities. Fewer number of optometrists available in the country, optometrists being deployed as refractionists in most of the settings, potential of optometrists not been optimally utilized by the employers, feeling of insecurity among other eye health professionals adopting optometrists as co eye care providers, feeling of insecurity among optometrists to invest in private practice because of small Nepalese market and more importantly unawareness among the public regarding optometry are some of the factors hindering optometry move towards an independent profession in Nepal.

However, there are opportunities for optometrists to come forward and work for

their individual identity. Existing cataract backlog, increasing cases of AMD, diabetic/ hypertensive retinopathy, glaucoma and other non communicable eye diseases in the country with increased life expectancy and changing dietary patterns will engage our ophthalmologists in managing these conditions for another couple of years. On the other hand, refractive error has been alarmingly increasing with changing vision demands and life style of the people. This is high time that we should develop a healthy referral system between ophthalmologists, optometrists and allied eye health professionals for improved eye care in Nepal.

Management of refractive error by the provision of glasses, contact lenses or low vision devices is an area where optometrists in the present context can exhibit their independency. Optometrists should enter into private practice in increasing numbers. An opportunity has to be given to the industries producing various ophthalmic products to enter the Nepalese market. Depending on the use and aff ectivity of these products in eye care they need to be promoted by the practicing optometrists. This will increase competition among the manufacturers, invite them to adopt various marketing strategies to bring awareness among the consumers. If a mechanism is set in coordination with the manufacturers the consumers can be oriented with the profession of optometry and the services they could provide. Independent practice in fact is a more secure form of employment for optometrists in Nepal. If the patient gets access to an optometric service as a primary eye care, this on a long run would help develop optometry as an independent profession as is commonly seen in developed

Optometrist- An Independent Eye Care Professional in Nepal

Subodh Gnyawali, OD, MPH

President, Nepalese Association of Optometrists

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countries.

The present structure for optometry education in Nepal also has to be modifi ed. The university has to have a department of optometry independent to the department of ophthalmology. It should be an optometrist to coordinate the educational activities of optometry rather than an ophthalmologist.

Increasing demand for optometry studies in the country cannot be coped with limited uptake of students at a single institute. More colleges off ering optometry degree has to come up so that more optometrists are produced, more are retained in the country, specialty services in optometry can be developed and there are more optometrists as private practitioners.


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Introduction

Glaucoma is a disease characterized by optic neuropathy secondary to retinal ganglion cell damage and presents with various morphological changes of optic nerve head with specifi c types of visual fi eld defect.

Glaucoma causes irreversible blindness. There were about 60 million cases of glaucoma in 2010 which is expected to rise to 80 million in 2020. One of the reasons for increase in incidence is the greater number of undiagnosed cases until it causes total blindness. In developed world, 40-60% of cases are undiagnosed while those in developing countries it is about 90%.

Recent researches and literatures have described that there are multi-factorial risk factors responsible for glaucomatous optic neuropathy apart from elevated IOP, which in past was considered as only the prime factor.

As already mentioned there are various factors responsible for pathogenesis of glaucoma. These factors are described here.

1. Neuronal loss in glaucoma by apoptosis:

Glaucomatous optic neuropathy is characterized by extensive retinal ganglionic cell (RGC) axon loss leading to cupping of optic nerve head (ONH). RGC damage and destruction in glaucoma occurs by apoptosis. Apoptosis is programmed cell death in the absence of infl ammation. It is characterized by DNA fragmentation, chromosomal clumping, cell shrinkage and blebing of cell membrane followed by breakdown of cells into membrane bound vesicals.

Caspase family of cysteine aspartyl specifi c protease has been found to be the central regulator for apoptosis.

When the enzyme is activated it initiates the proteolysis of cytosolic, a nuclear component leading to complete destruction of cells.

Role of increase IOP in the process of

Apoptosis

Process of RGC apoptosis is decreased by decreased IOP. IOP increase causes alteration in aqueous humour dynamics which can lead to trabecular changes like cytoskeletal changes, alteration of cellular and extra-cellular matrix. These changes are also co-related with level of IOP increase and duration of elevated IOP. Neuronal loss is seen in two phases in glaucoma. Initial phase when apoptosis is observed and late phase due to toxic eff ect of primary degeneration of neuron and constant exposure to increased IOP.

But about 25-35% of patients with glaucoma are diagnosed in individuals with normal IOP suggesting that elevated IOP is not the only risk factor.

Molecular mechanism of RGC apoptosis in

glaucomatous eye

In glaucomatous eye there is extensive remodeling of extra-cellular matrix (ECM). There is increase in TGF-β2, a matrix metalloproteinase (MMP1). Changes in ECM components can interrupt cell-cell and cell-ECM interaction that leads to death by apoptosis.

MMP are major matrix degrading enzyme and recent study has shown enhanced MMP-1 activity is seen in apoptotic RGC along with destruction of laminin indicating increased degradation of ECM at retinal site in response to increased IOP. Laminin helps in cells adhesion and survival by interaction with cellular integrins.

As IOP increases there is retrograde axoplasmic

Dr. Madhu Thapa

Pathogenesis of Glaucoma: IOP and beyond

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transport block which results in deprivation of supply of brain derived neuro trophin factor (BDNF) to RGC. BDNF is important for cell metabolism and cell survival. When BDNF is defi cient, there will be further progression of RGC apoptosis.

2. Vascular insuffi ciency:

Various reports have already described the strong association between vascular insuffi ciency and glaucoma. Diseases like migraine, peripheral vascular disease has been associated with glaucoma. This involves dysregulation of cerebral and peripheral vasculature.

There is increase in sensitivity to endothelin1 mediated vasoconstriction is observed in these vascular abnormalities. There is increase level of endothelin 1 found in aqueous and plasma of glaucomatous patients. Advanced age is also considered as an important risk factor for glaucoma and a progressive decline in cerebral and ocular perfusion seen on old age.

In healthy eye, a constant fl ow of blood is required to maintain retina and optic nerve head to meet its high metabolic demand. Effi cient auto regulatory mechanism is operated to maintain a constant fl ow in arteries, arterioles and capillaries. This auto regulatory mechanism is not as effi cient in old age as seen in young individuals.

In POAG and NTG patients have low systemic blood pressure leading to reduced ocular perfusion pressure.

Reduced in diastolic pressure is now recognized as an important risk factor for glaucoma.

Ocular blood fl ow = perfusion pressure/resistant to fl ow

Where, perfusion pressure= mean arterial BP-IOP

So, decrease in BP or increase in IOP leads to decrease in perfusion pressure to eye.

3. Role of glutamate in RGC death

Under hypoxic condition the retinal cells are

known to release glutamate which is essential neurotransmitter in central nervous system and retina in normal concentration. But when the concentration increases higher than the physiological state, it becomes toxic to neurons and toxicity depends upon the duration and extent of increase concentration.

Glutamate mediated neuro-transmission is via ionotropic glutamate receptor which includes N-methyl D aspartate (NMDA) receptors which after activation by glutamate causes opening of ion channels and leads to entry of extra-cellular Calcium and Sodium ions into neurons. This increase in concentration of sodium and calcium ions causes apoptosis.

Experimental administration of NMDA antagonist have shown to prevent glutamate induced toxicity.

4. Role of nitric oxide (NO)

Though nitric oxide plays an important role in body function where secreted in physiological quantities, its excessive production leads to various non neurological and neurological condition like glaucoma.

Nitric oxide synthesis (NOS) produce NO by oxidation of L-arginine and detected in 3 iso-forms. Excessive NO produced enters freely into the cells after diff usion through the local micro environment. It is a free radical radical of moderate reactivity but after entry into the cell it leads to production of highly reactive free radicals such as peroxinitrite after combining with super oxide (product of mitochondrial metabolism). It causes massive destruction of cell components. The increase in NO has also been observed in aqueous humour of glaucomatous patients. NOS can produce excessive NO under diverse condition such as exposure to cytokines and increased IOP.

5. Oxidative stress and glaucoma

Ocular tissue is provided with very effi cient anti-oxidant defense mechanism which includes glutathione and superoxide dismutase. Ascorbic acid also has an important protective role and high concentration is


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detected in vitreous humour, cornea, tear fi lm and aqueous humour.

Excessive free radicals and oxidative stress has been seen as an important factor in many ocular diseases such as cataract, age related macular degeneration and recent glaucoma.

Glaucoma patient have shown a signifi cant depletion of anti-oxidant potential in aqueous humor, decrease in plasma glutathione and increase in per oxidation in plasma.`

Conclusion:

Though there are various theories regarding pathogenesis of glaucoma, lowering IOP is the only therapeutic measure achieved till date to control the disease. Reduced IOP can defi nitely protect the optic nerve damage to remarkable extent.

Recent researches have shown that various agent with neuro protective eff ects may have signifi cant role in glaucoma management.

For instance calcium channel blockers are suggested to provide neuro protection by improving ONH blood supply. Likewise, carbonic anhydrase inhibitors are also thought to have similar eff ect.

Various agents with anti-apoptotic activities are also being studied in animal models. Caspases inhibitors are found to protect RGC apoptosis and erythropoietin when given intra-vitreally is found to increase RGC viability in animals.

Role of other neuro-protective agents like BDNF N-acetyl L-cystine, Nitrous oxide synthetase inhibitors, NMDA antagonist are also being studied.

None of the neuro-protective agents have been tried in human subjects yet. Better understanding of neurological basis of glaucoma can lead us to a new era of neuro-protective anti glaucoma in future.


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Craniosynostosis is the premature fusion of one or more of the cranial sutures accompa-nied by severe orbital abnormalities. This can occur as part of a syndrome or as an isolated defect. Prevalence of craniosynostosis is ap-proximately one in 2100 to 3000 infants (D. Taylor, 2005). Of more than 180 craniosynos-tosis syndromes; Crouzon’s and Apert’s syn-drome account for the majority of cases (Ki-monis, Gold, Hoff man, Panchal, & Boyadjiev, 2007). Pathogenesis

The growth of skull bones is driven primarily by the expanding growth of brain. There are diff erent sutures present in skull, the major ones being sagital, metopic, coronal and lam-boid. These sutures close at diff erent times with completion of closure occurring by 12 years of age (Kabbani & Raghuveer, 2004). Early closure of sutures hinders the growth of brain with brain growing in a direction par-allel to the closed suture, instead of normal perpendicular growth. The abnormal devel-opment of brain away from the prematurely closed suture results in abnormal structure of skull (D. Taylor, 2005). Abnormal anatomy of skull results in various complications including increased intra cranial pressure, abnormal fa-cial features, hearing and vision abnormalities, and intellectual impairment (Aleck, 2004). Etiology

Etiology of non syndromic craniosynosto-sis is unknown and is sporadic in many cases (Kabbani & Raghuveer, 2004). The syndromic craniosynostosis shows autosomal dominant, recessive or X-linked inheritance. Mutations in-volving transcription factor (TWIST) and three fi broblast growth factor receptors (FGFR) plays a major role in craniosynostosis (Kabbani & Ra-ghuveer, 2004; D. Taylor, 2005). Craniosyston-osis may also occur due to secondary causes like metabolic disorders such as hyperthyroid-ism, malformations like microcephaly, shunted hydrocephalus, encephalocele and mucopoly-saccharidosis.

Diagnosis

Diagnosis can be made with the help of clini-cal features but for confi rmation and to specify various syndromes radiological investigation are necessary most of the times (Kimonis, et al., 2007). Clinical diagnosis based on the ex-amination can be established soon after deliv-ery and is highly accurate, as high as 98-100%, for the single suture involvement (H. O. Taylor, Ramakrishnan, & Forrest, 2010). Computed tomography (CT) scan are widely used for diagnosis and to aid in surgical plan-ning and rule out other associated intracranial anomalies. Magnetic resonance imaging is re-served for cases with syndromic craniosynos-tosis and aids in diagnosis of associated anom-alies like hydroceplahlus, cerebral vascular anomalies. Prenatal ultrasound is appropriate for diagnosis of various craniosynostosis from second trimester onward (D. Taylor, 2005). Ocular examination:

Physical examination comprising close inspec-tion of lid position, size and shape of palpebral fi ssure is essential. Careful inspection of ocu-lar motility in all gazes, cycloplegic refraction, pupil and fundus evaluation are mandatory (Cohen, 2000). Exophthalmometer readings, intraocular pressure, visual fi eld evaluation, corneal sensitivity and examination under an-esthesia should be performed when indicated. Special eff ort should be directed to measure interpupillary distance, inner and outer can-thal distance, palpebral fi ssure size, shape and symmetry and slant of palpebral fi ssure (Co-hen, 2000). These baseline measurements pro-vide data for future evaluation and to monitor progression. Crouzon Syndrome

Crouzon syndrome was fi rst described by Louis Edouard Octave Crouzon in 1912. This is one of the common type of craniosyntnosis; accounting for 5% of craniosynostosis with incidence of 1 in 25,000 live births (Kabbani & Raghuveer, 2004). Half of the cases are fa-milial with complete penetrance but variable

Craniosynostosis Mahesh Raj joshi

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expressivity and other half are new mutations (D. Taylor, 2005). Mutations in FGFR 2 gene on chromosome 10 are causative with autosomal dominant inheritance (Kabbani & Raghuveer, 2004; Kimonis, et al., 2007). Characteristics facial features include short an-terio-posterior head distance, hypertelorism, beaking of nose, hypoplasitc maxilla and mid face hypoplasia (Kanski, 2007; D. Taylor, 2005). The synostosis of cornonal or multiple suture usually develops during fi rst year of life and completes by 2 or 3 years of age (D. Taylor, 2005). Ocular involvement

The structural deformity results in widely separated orbits; hypertelorism and laterally rotated orbital axis known as exorbitism. Pro-ptosis is the characteristic feature (Kreiborg & Cohen, 2010). Shallowing of orbits due to ar-rested growth of maxilla and zygoma result in proptosis (Kanski, 2007; D. Taylor, 2005). Severe proptosis causes exposure of ocular structures resulting in frequent conjunctivitis, keratitis. In extreme cases luxation of globes anterior to eyelids (Kanski, 2007) and spontaneous pro-plapse of globe, provoked by coughing may occur (D. Taylor, 2005). Strabismus of V paterrn exotropia and hyper-tropia is common (Kanski, 2007). Exotropia has been reported in three fourth of patients with Crouzon syndrome (Kreiborg & Cohen, 2010) while others have reported a lower oc-currence, 39% (Gray, Casey, Selva, Anderson, & David, 2005). Anomalous extra ocular mus-cles formation and insertion has also been re-ported. Refractive error is common with ma-jority having hypermetropia (Hertle, Quinn, Minguini, & Katowitz, 1991). A study reported 77% of patient with ametropia and 57% with hypermetropia of more than 2 dioptres (Gray, et al., 2005). Visual impairment in crouzon syn-drome is high, a study reported visual impair-ment in 35% of patients in one eye and 9% in both eyes (Gray, et al., 2005). Amblyopia due to various etiology is the most common cause of visual impairment (Gray, et al., 2005; Hertle, et al., 1991). Exposure Conjunctivitis and keratopathy is

also common with studies reporting 15% to half of patients reporting the condition (Gray, et al., 2005; Kreiborg & Cohen, 2010). Optic at-rophy due to increased Intra cranial pressure is one of the major cause of severe visual im-pairment (Gray, et al., 2005). In addition, there have been rare reports of aniridia, anisocoria, blue sclera, cataract, corectopia, ectopia len-tis, glaucoma, iris coloboma, megalocornea, microcornea, nystagmus, and optic nerve hy-poplasia (Cohen, 2000; Fries & Katowitz, 1990). Apert Syndrome

Apert Syndrome may involve all the cranial sutures and is most severe form of cranio-syntnosis (Kanski, 2007). It constitutes 4% of all craniosynostosis and occurs in one in every 65,000 live births (D. Taylor, 2005). Inheritance is autosomal dominant but majority of cases are sporadic due to FGFR2 mutations with sig-nifi cant association with older parental age (Kanski, 2007; Kimonis, et al., 2007; D. Taylor, 2005). Males and females are equally aff ected (Cohen, 2000). The features are similar to Crouzon syndrome but is characterised by broad thumbs and great toes, and symmetrical syndactaly involv-ing the second to fourth or fi fth fi ngers and toes (D. Taylor, 2005). Mental retardation is also commonly associated with Apert syndrome (D. Taylor, 2005) with 30% of cases being re-ported with retardation (Kanski, 2007). Ocular features:

Ocular features are similar to the crouzon syn-drome but less severe with shallow orbits, proptosis and hypertelorism (D. Taylor, 2005). Most ocular pathology is due to shallow orbits and resulting proptosis. Corneal exposure may lead to traumatic injury and exposure keratitis. Eyebrows may have break in continuity prob-ably due to underlying bony defect (Cohen, 2000). Optic atrophy is very uncommon (Co-hen, 2000). V pattern exotropia is a characteristic feature (Kreiborg & Cohen, 2010). Strabisumus is due to various defects in superior rectus and su-perior oblique muscles ranging from under-action of the muscles to anomalous insertion and complete absence of superior rectus and


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superior oblique muscles complex (Green-berg & Pollard, 1998; Jadico et al., 2006). Rare association of keratoconus, ectopia lentis and congenital glaucoma has been reported (Kan-ski, 2007; D. Taylor, 2005). Manangement of Craniosynostoses Craniosynostoses are best managed by mul-tidisplinary approach consisting of various health care professionals; plastic surgeons, eye care specialist, ENT specialist, neurosur-geons, oral surgeons and others (Panchal & Uttchin, 2003). Various ocular disorders associated with cra-niosynostosis such as exposure conjunctivitis and keratitis should be treated appropriately with lubricating drops and ointments. Am-blyopia due to various causes represents the most common cause of visual impairment and treatment should be directed towards achiev-ing best visual outcome. Surgical procedure is indicated in early infancy preferably during fi rst 6 months of life to pre-vent further progression (Panchal & Uttchin, 2003). Surgery should be done immediately if vision is threatened by the risk of optic atro-phy or corneal exposure (D. Taylor, 2005). The main aim of surgery are to excise the fused suture to allow the normal growth as well as to normalise the clavarial shape (Panchal & Uttchin, 2003). Decompressive osteotomy is the surgery of choice to reduce increased in-tracranial pressure in early life which can be combined with craniofacial techniques (D. Taylor, 2005). Other surgical methods include removal of prematurely fused suture to com-plicated procedures such as cranioplasty and orbital remodelling. References

Aleck, K. (2004). Craniosynostosis syndromes in the genomic era. Semin Pediatr Neurol, 11(4), 256-261. Bayraktar, S., Bayraktar, S. T., Ataoglu, E., Ayaz, A., & Elevli, M. (2005). Goldenhar’s syndrome associated with multiple congenital abnor-malities. J Trop Pediatr, 51(6), 377-379. Cohen, M. M. (2000). Craniosynostosis : diag-nosis, evaluation, and management. New York [u.a.]: Oxford Univ. Press.

Dixon, M. J. (1996). Treacher Collins syndrome. Hum Mol Genet, 5 Spec No, 1391-1396. Esparza, J., Hinojosa, J., Garcia-Recuero, I., Ro-mance, A., Pascual, B., & Martinez de Aragon, A. (2008). Surgical treatment of isolated and syndromic craniosynostosis. Results and com-plications in 283 consecutive cases. Neuro-cirugia (Astur), 19(6), 509-529. Fries, P. D., & Katowitz, J. A. (1990). Congenital craniofacial anomalies of ophthalmic impor-tance. Surv Ophthalmol, 35(2), 87-119. Gray, T. L., Casey, T., Selva, D., Anderson, P. J., & David, D. J. (2005). Ophthalmic sequelae of Crouzon syndrome. Ophthalmology, 112(6), 1129-1134. Greenberg, M. F., & Pollard, Z. F. (1998). Ab-sence of multiple extraocular muscles in cra-niosynostosis. J AAPOS, 2(5), 307-309. Grewal, A., Bhat, D., Sood, D., Garg, S., Singh, A., Bharti, R., et al. ( 2005). Goldenhar Syndrome : Anaesthetic and Airway Management. J An-aesth Clin Pharmacol, 21(3), 313-316. Harb, E., & Kran, B. (2005). Pfeiff er syndrome: systemic and ocular implications. Optometry, 76(7), 352-362. Hertle, R. W., Quinn, G. E., Minguini, N., & Ka-towitz, J. A. (1991). Visual loss in patients with craniofacial synostosis. J Pediatr Ophthalmol Strabismus, 28(6), 344-349. Hertle, R. W., Ziylan, S., & Katowitz, J. A. (1993). Ophthalmic features and visual prognosis in the Treacher-Collins syndrome. Br J Ophthal-mol, 77(10), 642-645. 5 | Jadico, S. K., Young, D. A., Huebner, A., Edmond, J. C., Pollock, A. N., McDonald-McGinn, D. M., et al. (2006). Ocular abnormalities in Apert syndrome: genotype/phenotype correlations with fi broblast growth factor receptor type 2 mutations. J AAPOS, 10(6), 521-527. Kabbani, H., & Raghuveer, T. S. (2004). Cranio-synostosis. Am Fam Physician, 69(12), 2863-2870. Kanski, J. J. (2007). Clinical ophthalmology : a systematic approach. Edinburgh; New York: Butterworth-Heinemann/Elsevier. Kimonis, V., Gold, J. A., Hoff man, T. L., Panchal, J., & Boyadjiev, S. A. (2007). Genetics of cranio-synostosis. Semin Pediatr Neurol, 14(3), 150-


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161. Kreiborg, S., & Cohen, M. M., Jr. (2010). Ocu-lar manifestations of Apert and Crouzon syn-dromes: qualitative and quantitative fi ndings. J Craniofac Surg, 21(5), 1354-1357. Lehman, S. (2006). Strabismus in craniosynos-tosis. Curr Opin Ophthalmol, 17(5), 432-434. Marszalek, B., Wojcicki, P., Kobus, K., & Trzeciak, W. H. (2002). Clinical features, treatment and genetic background of Treacher Collins syn-drome. J Appl Genet, 43(2), 223-233. Mehta, B., Nayak, C., Savant, S., & Amladi, S. (2008). Goldenhar syndrome with unusual fea-tures. Indian J Dermatol Venereol Leprol, 74(3), 254-256. Panchal, J., & Uttchin, V. (2003). Management of craniosynostosis. Plast Reconstr Surg, 111(6), 2032-2048; quiz 2049. Tay, T., Martin, F., Rowe, N., Johnson, K., Poole, M., Tan, K., et al. (2006). Prevalence and causes

of visual impairment in craniosynostotic syn-dromes. Clin Experiment Ophthalmol, 34(5), 434-440. Taylor, D. (2005). Pediatric ophthalmology and strabismus. Edinburgh [u.a.]: Elsevier Saun-ders. Taylor, H. O., Ramakrishnan, A., & Forrest, C. R. (2010). Advances in the Diagnosis of Cranio-synostosis. European Paediatrics, 4, 66–71. Touliatou, V., Fryssira, H., Mavrou, A., Kanavakis, E., & Kitsiou-Tzeli, S. (2006). Clinical manifesta-tions in 17 Greek patients with Goldenhar syn-drome. Genet Couns, 17(3), 359-370. Trainor, P. A., Dixon, J., & Dixon, M. J. (2009). Treacher Collins syndrome: etiology, patho-genesis and prevention. Eur J Hum Genet, 17(3), 275-283.


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The most recent defi nition of dry eye published in Dry Eye Workshop (DEWS) report (2007) 1 was as “Dry eye is a multifactorial disease of the tears and ocular surface that results in symptoms of discomfort, visual disturbance, and tears fi lm instability, with potential damage to the ocular surface. It is accompanied by increased osmolarity of the tear fi lm and infl ammation of the ocular surface.”

According to the defi nition, symptoms of discomfort are given priority as compared to signs. A new element is mentioning visual disturbance as a dry eye symptom. This is particularly important for contact lens wearers.

Studies consistently show that of all the symptoms experienced by contact lens wearers, that of dryness is most frequent.2, 3 In a survey of 100 contact lens wearers, only 25% of all patients said that they experienced no dryness symptoms.4

Contact lens wear may cause hyperosmotic shift of the tear fi lm.5, 6 The causes for this may be reduced tear stimulation caused by decreased corneal sensitivity, thus reducing blink rate, increased lens induced tear hyper-evaporation or accumulation of lens deposits in the tear fi lm. Therefore, if a person has a borderline or moderate dry eye to start with, contact lens wear may comprise tear function to the extent that it begins to cause symptoms.

Most researchers agree today that dry eye could be divided into hyposecretive and hyperevaporative dry eye.7 (Hyper) evaporative dry eye is by far the most frequent type of dry eye.6-8 Modern lifestyle, which invariably includes computer work, is perhaps the main culprit for reduced blink rate.9 This

is particularly important in contactology, since this cause of hyperevaporative dry eye is frequent among contact lens wearers compounding the problem. Hyposecretive dry eye is mainly found among the elderly and hyperevaporative among younger population from which most contact lens wearers are recruited.

Main symptom of hyperevaporative dry eye is tearing, caused by the increased evaporation and condensation of aqueous tears on palpebral margins, particularly in cold weather. Hyposecretive dry eye mainly presents symptoms of burning, grittiness and foreign body sensation.

Diagnostic tests

1) Tear fi lm break up time (TBUT)

This test is regarded as pivotal in dry eye diagnostics .As mentioned in DEWS Report dry eye defi nition, tear fi lm instability is one of the main causes of dry eye, and that is what TBUT test measures. It is easy and quick to perform and moderately invasive though it has dubious repeatability and lack of consensus reading cutoff value between normal and pathologic values: older papers advocate 10 seconds, while several newer ones reduce it to 5 secs.

2) Schirmer test

Historically it was the fi rst test used to diagnose dry eye. It still has a place in it, but with strictly defi ned purpose: only to measure the quantity of aqueous tear production. In hyperevaporative dry eye we often see tears dripping from the test strip-interpreting this result as “normal tear function” would mean missing the opportunity to properly diagnose and treat patient’s tear dysfunction. 10 mm of test strip wetted with tears in 5 minutes is

Current Diagnosis and Management of Dry Eye

Digen SujakhuOptometrist, (B.Sc. Env. Sci, B. Optom.,T.U.)

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generally accepted.

3) Lid parallel conjunctival folds (LIPCOF)

A group of authors led by Prof. Hoeh in 1995 published the paper Lid-parallel conjunctival folds are sure diagnostic signs of dry eye.10

according to the authors, the height and/or number of bulbar conjunctival folds parallel to the temporal margin of the lower eyelid are observed. Before assessment, lower eyelid is briefl y lifted from the eye surface-if folds disappear, they indeed are what is described as LIPCOF.

Findings are ranked as follows:

Grade 0: no folds – normal fi nding (not dry eye)

Grade 1: one fold above the normal tear meniscus height-mild dry eye

Grade 2: multiple folds up to the height of normal tear meniscus-moderately dry eye

Grade 3: multiple folds above normal tear meniscus height-severe dry eye.

It is non-invasive method, takes very short time to perform and has no additional costs as it requires use of no test strips, dyes etc. This may be particularly practical in dry eye screening in contact lens wearers, especially regarding soft contact lens wearers. One recent study reaffi rms the potential value of LIPCOF in dry eye screening, placing cutoff value between grades 1 and 2.11

4) Lid Wiper Epitheliopathy (LWE)

Korb et al found correlation between dry eye symptoms and the appearance of inner upper eyelid lid wiper portion staining.12in symptomatic patients, 88% had LWE13. Lid wiper can be stained either with fl uorescein or with lissamine green.

Lid wiper is part of inner margin of upper eyelid that exerts most pressure on the eyeball during blinking. Korb et al explain appearance of staining on lid wiper with decreased lubrication in dry eye and consequently increased friction. LWE has been graded in Prof. Korb’s initial paper, and more precisely in

his more recent paper.12, 13 though not widely used it is a promising concept. Its indisputable value is in drawing attention to increased friction as one of the main causes of dry eye symptoms, the fact that was previously overlooked.

5) Meibomian gland expression

It is one indirect way of assessing lipid layer function. It was initially as well as most recently described by Prof. Korb in 2008.14 by manually applying pressure on eyelid for 10-15 seconds; we can assess quantity and appearance of meibum. It is non-invasive, requires no additional equipment and at least may give us general idea about lipid layer secretion.

6) Ocular surface staining

Ocular surface staining marks a more serious form of dry eye, one in which protective role of tear fi lm has been compromised. Typically, dry eye exhibits staining in the palpebral aperture and at 6 o’clock. However, as it is with other signs of dry eye, staining correlates poorly with symptoms: one may have pronounced dry eye symptoms without any surface staining and vice versa.

Following diagnostic sequence is recommended, which will not take too much time, and does not require any additional equipment.

1. Case history

2. Slit lamp examination of lid margin for blepharitis

3. TBUT

4. LIPCOF

5. Meibomian gland expression

6. Ocular surface staining

Therapeutic approach

Main goals in dry eye therapy are fi rstly, to alleviate symptoms and thus enhance patient’s quality of life, secondly, to prevent development of possible complications of dry eye, such as viral or bacterial infection or scarring. And at last but not least, not to


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minimize the side eff ects of the therapeutic measures.

Artifi cial tears

These were and still are the mainstay of any dry eye therapy. Nowadays, their role in lubrication and, most recently, prevention of evaporation, are increasingly gaining importance.

Rewetting

By volume, all artifi cial tears are 99% water. However, what makes them diff erent from 100% water are demulcents that keep water on the eye long enough to provide adequate rehydration. A demulcent (derived from the Latin demulcere, ‘caress’) is an agent that forms a soothing fi lm over a mucous membrane relieving minor pain and infl ammation of the membranes. What is more important, it can swell to many times its dry volume without losing its initial properties. After absorbing water it can slowly release it, providing long lasting rehydration.

Lubrication

Compounds with proven lubricating eff ects are nowadays available in rewetting eyedrops. By reducing friction, dry eye symptoms such as grittiness and foreign body sensation are reduced.

Evaporation prevention

Though there was not much available to off er diagnosed hyperevaporative dry eye caused by lipid layer dysfunction, recently there are formulations with lipid layer substitutes, presenting perhaps the biggest change in artifi cial tear therapy since the introduction of hydroxypropyl methylcellulose (HPMC) as an active ingredient of artifi cial tears in the early fi fties.

Preservatives

Benzalkonium chloride (BAK) is still the most frequently used preservative. As a cationic surfactant (detergent), it disrupts lipid layer of the tear fi lm and causes tear break-up. Therefore, BAK-containing eyedrops may actually worsen the symptoms of

hyperevaporative dry eye by dissolving lipid layer. So monodose preservative-free artifi cial tears or those with preservatives with less adverse eff ects, such as higher molecular weight, are compounds of choice here.

Other therapeutic measures

Since air-conditioned environment has low relative humidity, natural ventilation is better option wherever possible. Also placing computer below eye level will narrow the eye aperture and thus reduce ocular area from which tears evaporate.

Treat any eyelid disease (blepharitis), eyelid hygiene

Reduced blinking in CL wearers may cause Meibomian gland orifi ces to clog, thus compromising lipid layer function and increasing tear evaporation. To prevent this, eyelid hygiene (cleaning of gland orifi ces with clean water of commercially available lid scrubs) is recommended on daily basis.

Assess contact lens care regimen

Improper lens care (lens worn too long, use of improper cleaning solution etc.) may also cause tear fi lm function to be excessively compromised.

Change of CL material

In case none of the above can help, a change to silicone-hydrogels (SiHs) may help. It has been claimed that ACUVUE OASYS with HYDRACLEAR PLUS (Senofi lcon A) lens has improved performance, especially for patients in challenging environments who may have issues with lens comfort and dryness.

Change of lens type or wear regimen

If gas permeable CLs cause severe discomfort due to ocular dryness, change to soft material may be considered. In case of severe intolerance, consider temporary or permanent reduction of wear time or complete discontinuation of CL wear.

In CL practice, diagnosis of dry eye is compulsory and should include number of tests in order to defi ne the type of dry eye,


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as well as the condition of the ocular surface including potential damage such as staining, lid wiper epitheliopathy, LIPCOF. Special attention should be payed on lens material and its property, lens modality and if applicable CL solutions. Careful CL selection and follow up of each case will improve dry eye related symptoms and ocular surface health.

References:

1. Defi nition and Classifi cation of Dry Eye. Report of the Diagnosis and Classifi cation Subcommittee of the Dry Eye Work Shop (DEWS). Ocul Surf 2007; 5:75-92.

2. MacMonnies CW and Ho A. Marginal dry eye diagnosis: History versus biomicroscopy. In: The Pre-ocular tear fi lm in Health, Disease, and Contact Lens Wear 1986; ed. Holly FJ: p. 32-40.

3. Brennan NA and Efron N. Symptomatology of HEMA contact lens wear. Optom Vis Sci 1989; 66: 834-838.

4. Petricek I, Prost M, Popova A. The diff erential Diagnosis of Red Eye: A survey of Medical Practitioners from Eastern Europe and the Middle East. Ophthalmologica 2006; 220: 229-237.

5. Martin DK. Osmolarity of tear fl uid in the contralateral eye during monocular contact lens wear. Acta Ophthalmol (Copenh.) 1987; 65: 551-555.

6. Farris RL, Stuchell RN and Mandel ID. Basal and refl ex human tear analysis. I. Physical measurements:

Osmolarity, basal volumes, and refl ex fl ow rate. Ophthalmology 1981; 88: 852-857.

7. McCauley JP, Shine WE, and Aronowicz J et al. Presumed Hyposecretory/hyperevaporative KCS: Tear Characteristic. Trans Am Ophthalmol Soc 2003; vol 101:141-154.

8. TearLab presentation at TFOS, Florence, 2010.

9. Patel S, Henderson R, Bradley L, et al. Eff ect of visual display unit use on blink rate and tear stability. Optom Vis Sci 1991; 68:888-892.

10. Hoeh H, Schirra F, Kienecker C, Ruprecht KW. Lid parallel conjunctival folds are a sure diagnostic sign of dry eye. Ophthalmologe. 1995; 92(6):802-8.

11. W. Sickenberger, H. Pult, B. Sickenberger. LIPCOF and contact lens wearers- anew tool to forecast subjective dryness and degree of comfort of contact lens wearers. Contactologia 2000; 22: 74-79.

12. Korb DR, Herman JP, Greiner JV, Scaffi di RC, Finnermore VM, Exford JM, Blackie CA, Douglass T. Lid Wiper Epitheliopathy and dry Eye symptoms. Eye and Contact Lens 2005; 31(1):2-8.

13. Korb DR, OD, Herman JP, Blackie CA, et al. Prevalence of Lid Wiper Epitheliopathy in Subjects With Dry Eye Signs and Symptoms. Cornea 2010; 29:337-383.

14. Korb DR, Blackie CA. Meibomian gland diagnostic expressibility: correlation with dry eye symptoms and gland location. Cornea 2008; 27(10):1142-1147.


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As an optometry graduate, I think I have a pretty good experience on how it feels to be an optometry undergraduate student in Nepal. We have to bear a huge load of course curriculum which ranges from human anatomy,physiology, pharmacology, community medicine, optics, detailed optometric theory and methods, vision science, practical /clinical postings, presentations, ocular diseaseto a fi nal project work. These are the materials that optometry students usually learn during the whole four years of undergraduate educationwhich might be a bit hectic for some people. This article is my own experience on how I survived my undergraduate years as an optometry student and some tips on how to make your four years interesting without being bored or frustrated at all.

Before I was a student of optometry at Institute of Medicine, I had never heard of the word Optometry. But, as soon as I got enrolled in Optometry, and after few months, I think there was no one who would know more about optometry than me. I dug into each and every source ranging from magazines to internet resources. And what I found was optometry as the most fascinating and challenging subjects in life sciences. Though there are very less stuff of surgery and medicine (for those who think surgery and medicine are the only ways to make people feel better), I found optometry as a profession in which a small contribution of yours brings a huge smile on others’ face. For example, vision therapy for children struggling with learning and providing low vision devices to those people who were told that there is nothing that can be done to their eyes to make them read the newspaper again. This is

a real triumph in your life, if you agree with my view. The more interesting part is optometry is interrelated with fi elds like psychology, neuroscience andvision science. These were some of the motivating factors for me being an enthusiastic learner in optometry.

I was always a curious guy and still I am. I want to think out of the box besides the traditional way of learning. I wanted to get updated to current developments and also was curious in learning new ways to explore if there are anyways that I can contribute to the betterment of mankind. That is the reason I chose my career in research. The views and methods I follow might not be generalised to everyone but I think they apply to most of the people if they want to perform better. The most common activities in undergraduate years in optometry education in Nepal are: academic presentations (Ophthalmology/optometry, attending or presenting) clinical posting rotations and attending lectures. This is a bit frustrating that there is nothing you can do in lectures given by your lecturers or instructors to make it more interesting. The only thing you can do is be more interactive (asking questions, contributing newer knowledge, if you are sure) and make the class more active rather than just listening. But, there are a lot of things you can do to make your time exciting in clinical postings, self-learning and attending or giving presentations which I tried during my undergrad years. Here are some of them:

Clinical rotations:

Be a very careful observer

• Watch carefully how a certain procedure is done by your seniors/instructors

How not to be bored during undergraduate

optometry years and perform better?

Nabin Paudel, PhD Candidate

University of Auckland, Auckland, NZ

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• Note down the procedure or keep in mind ( for searching about that on textbook or internet when you go home)

• Learn from the basics and don’t leap at once

Be Polite and ask things you don’t know

• Speak softly to patients so that they don’t get irritated by the procedure you are doing.

• Make feel them that you are taking care of them not only learning from them.

• If you don’t know something,(even a very simple thing) ask to your friends/seniors/instructors(this may help you from doing blunders and potential harm)

Be interactive and laborious

• Discuss the fi ndings of the day with friends, if there are any interesting fi ndings

• Learn all available procedures within your four years step by step but don’t be over-smart

• A lot of instruments might be kept unused, explore them and know how to use them among yourselves and then on patients.

Tidy and professional:

• Don’t make crowd among each other and behave immaturely (act like a professional).

• Be tidy and on time.

Learn to enjoy some hard days:

• Though there may be some long days, learn to enjoy by seeing the smile on your patient’s face as it is the greatest pleasure of the day which will make you day.

Presentations:

Try to attend as many presentations as you can.

If you are attending:

• Takes notes of the presentation materials ( might be useful for you in the future)

• Contribute your ideas and knowledge if

you are sure about it and have the latest information relevant to the matter.

If you are presenting:

• Start preparing for it very early rather than in the last minute

• Be on time on the day of your presentation

• Add humour to your presentation (but must be somehow relevant to your topic)

• Add graphics, cartoons and animations (not much slide transition and color patterns) so that the audience don’t sleep during your session

• Be confi dent while presenting and open questions for discussions to the audience

• Don’t read the slide (as the audience will read themselves) rather try to explain in a simple way.

• Use fl ow charts, diagrams to demonstrate the results or methods as a picture is worth a thousand words.

Self-Learning/Reading for exams:

Be creative and think out of the box:

• Besides lecture notes and standard text books scan journal articles on your study topic

• Be a bit extra than your friends on answering questions (except in MCQs and objective)

• Internet is a bucket full of fi shes in academic resources so explore it.

• Include fi gures in your answers if relevant and possible.

• See lectures from international universities which may have new information and new methods for a certain procedure.

• Try to solve exam papers and numerical from international university, professional licencing exam papers like OCANZ, University of Melbourne. (for fi nal year students and are available on the internet).


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Research Project/Project work:

• Select a topic which you think will be new in your fi eld and you are interested

• Know detailed background information about the topic you want to study

• See core papers (similar papers to your proposed chosen topic)

• Discuss the feasibility of the paper with your proposed supervisors

• Try to contact international professors or any academics and ask for suggestions on your topic if they have done similar kind of study previously. ( Most of the academics are good people and are always willing to help if you request them)

• Take your project as a challenge and be excited that you are going to fi nd something new

• Never manipulate your data. It is your learning phase, it is an undergraduate project work not a PhD and you are very lucky to have this project in your course which is a signifi cant advantage for further studies.

These were some of the things that I tried to follow during my undergraduate years though I might not be able to follow all of them. I am very hopeful that these tips might be helpful for any optometry undergraduate students all around the world.

Some of the internet resources those I explored as an undergraduate student and might be of interest to optometry students are:

www.optometry.co.uk (Clinical articles)This website has very good clinical articles ranging from ophthalmic optics, ocular disease to contact lens.

h t t p : / / w w w . o p t . i n d i a n a . e d u / r i l e y /HomePage/1lecturenotes.html , has lectures notes on various diagnostic procedures like slit lamp, BIO, etc

http://www.pacificu.edu/optometry/ce/online_ce.cfm , has courses especially designed

for optometrists but useful for everyone.

http://www.academy.org.uk/ , has very useful resources on procedures, lectures from City University, Aston University etc. More interesting is a virtual patient clinic where you can examine patients online and diagnose them. It is awesome.

http://www.odwire.org/a forum of optometrists especially from USA where there are a lot of optometry related discussions (academic and non-academic)

http://www.optiboard.com/ a forum of optometrists, opticians and other eye care professionals with a lot of dispensing related information.

http://www.ce4optometry.com/web/ clinical articles, some of them are free and for some you may have to pay money.

http://www.eyeceonline.com/ hundreds of very interesting articles especially designed for optometrists and opticians.

http://www.nova.edu/hpd/otm/index.html Optometric theory and methods, presentation, lectures from NOVA College of Optometry.

http://viperlib.york.ac.uk/ if you want to learn a bit more of vision science, explore this. Heaps of vision science stuff from illusions to lectures.

There are hundreds of resources in the web, the only thing is you need to explore and get them. I hope your journey for search of new knowledge will start soon. I hope you will fi nd the above resources helpful. If you think I can be of help in any of your activities from academic to research works, feel free to mail me on the following mail address. Thank you so much.


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Before planning for any invasive surgical intervention, it is important to give the relevant and comprehensive information of the disease process and alternative treatment methods to the patients. Historically consent was not the important part of medical practice as the involved physician is expected to approach the appropriate intervention which is best for the patients. Those days’ doctors did not explain what they were doing to the patients and why they were doing it. But, in the 20th century, it has become an important part of medical practice and often a legal necessity for surgical procedures.1,2 The concept of patient consent evolved from a judgement in the US supreme court during 1914 and it became a part of international law following world war two with the basic concept that patient consent is mandatory prior to performing any invasive procedures. 3, 4

The basic concept of the consent revolves around the possible medico-legal defences for the doctors and the right of the patients to make his own decision for the future management of the health conditions.5 once the patient is informed, he is given chance to make decision whether or not to go through with a procedure. Most times it is recorded so that there will be no confusion later. This documentation can become important in the event that there is a dispute about whether or not medical consent was obtained before a procedure.

It is the right of the patients to refuse to consent or to consent selectively. When someone lacks the capacity to give consent legally, she or he may still be consulted during the process and may also be informed about the procedure.

The ethical form of consent is regarded as the shared process of decision making.6 Shared decision making thus allows both patient autonomy and physician responsibility. In the socioeconomically developing countries like Nepal it is likely that patient would be less determined to decide about the subsequent management plans of their health conditions and they prefer to get decision made by the involved physician. Patients undergoing eye surgeries are concerned of their improvement of vision; questions being when the vision would improve and the overall risks of losing vision from the operation.7 It is a general legal and ethical principle that a valid informed consent must be obtained before starting treatment.9 In the western countries, touching a patient without valid consent may invite a civil or criminal off ence.10,11 Many factors, such as access to information, emphasis on patients’ autonomy and medico-legal considerations have become part of the process of informed consent.

A recent study in the Annals of Internal Medicine highlights the importance of informed consent discussions, the role they may play in reducing malpractice risks, and the fact that patients often have unrealistic expectations regarding the potential benefi ts of procedures. In a study by Pimentel et al carried out in patients with cancer, most of the patients wanted to know as much as possible about their illness and treatment.12 Patients should establish a trustful relationship with the surgeon who operates on them.11 Kiss CG et al.13 report that patients’ prefer to abstain from taking part in the management decision regarding their care. It is vital that the informed

Consent: A necessary step before medical intervention

Sanjay MarasiniClinical Optometrist

Department of OphthalmologyDhulikhel Hospital/Kathmandu University Hospital

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consent requires us to do more than tell our patients about the risks of the treatments we off er them and make sure that they fully understand the anticipated benefi ts.

atients want to know about the important complications8 although the preference has been observed to vary with the education level and socioeconomic status of the patients. Kang DK observed that 35.6% of their patients’ did not want to know about the complications and risk of surgery which is similar to our observations. It is understandable that diff erent patients with diff erent anxiety levels and interest would express diff erent degrees of acceptance or tolerance to how much information they would want to know prior to undergoing surgery.10 It is postulated that providing information about risks and complications causes undue and unnecessary anxiety.14

From the ethical point of view; the consent will be valid only when the patient feels that it would have been possible to refuse and change their mind. It is observed that for many patients consent means the medico-legal document which is generally regarded to be from the doctor’s perspective. Although, some might be anxious, it should not mean that they do not need information. The information helps patients to cope with the treatment and better surgical outcomes.

References

1. Nisselle P. Informed Consent. N Z Med J 1993;106:331–2.

2. Health and Disability Commissioner (Code of Health and Disability Services Consumers’ Rights) Regulations (1996). Wellington, New Zealand: Government Printer.

3. Nick WV. Informed consent—the new decisions. Bull Am Coll Surg 1974;59:12-7

4. Borelli N. The Nuremberg Code, Informed Consent, and Involuntary Treatment. JAMA. 1997;277(9):712-712. doi:10.1001/jama.1997.03540330034025

5. Cheung D, Sandramouli S. The consent and counselling of patients for cataract surgery: a prospective audit. Eye 2005; 19: 963–7

6. Seeking Patient’s Consent: The Ethical Considerations. General Medical Council publication: London.

7. Elder MJ, Suter A. What patients want to know before they have cataract surgery? Br J Ophthalmol 2004;88:331-2

8. Marasini S, Kaiti R, Mahato KR, Nepal BP. Informed consent among patients who need to undergo eye surgery: A qualitative study assessing their attitude, knowledge and anxiety level. (Unpublished data)

9. Department of Health. Good practice in consent implementation guide: consent to examination or treatment. 2001

10. Kang KD, Abdul Majid AS, Kwag JH, Kim YD, Yim HB. A prospective audit on the validity of written informed consent prior to glaucoma surgery: an Asian perspective. Graefes Arch Clin Exp Ophthalmol. 2010 May;248(5):687-701. Epub 2009 Oct 15.

11. Ghulam AT, Kessler M, Bachmann LM, Haller U, Kessler Tm. Patients’ satisfaction with the preoperative informed consent procedure: a multicenter questionnaire survey in Switzerland. Mayo Clin Proc. 2006 Mar;81(3):307-12.

12. Pimentel FL, Ferreira JS, Vila Real M, Mesquita NF, Maia-Goncalves JP. Quantity and quality of information desired by Portuguese cancer patients. Support Care Cancer. 1999 Nov;7(6):407-12.

13. Kiss CG, Richter-Mueksch S, Stifter E, Diendorfer-Radner G, Velikay-Parel M, Radner W. Informed consent and decision making by cataract patients. Arch Ophthalmol. 2004 Jan;122(1):94-8.

14. Stenchever MA. Too much informed consent?. Obstet Gynecol. 1991 Apr;77(4):631.


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All people, whatever are their statuses, whoever are they; somehow are found to practice traditional treatment approach to diseases, not to mention eye. However the severity of the practice diff ers in many ways; according to age, educational level, gender, socio-economical background, occupation, ownership of health insurance, rural location of residence etc. The routes of administration of the Traditional Ocular Medications (TOMs) are mainly topical, oral, face-wash, fume-bath, shower and inhalation. When we explore the whys of the traditional ocular medications being still prevalent in the societies, we come across diff erent logical answers. If my friend and one of my cousins got benefi tted with the medications, then why can’t I try? Someone may reply by asking. If the given area is far more rural then one may fi nd diffi culty in accessing the modern eye care facility, so they are bound to have TOMs. By occupation, people who are farmers and unemployed tend to have excessive practices of TOMs. It may be because the famers are almost every time in the farming or jungle area so they can cherry-pick the medicines easily and seek counseling from traditional healers as well. The unemployed people might not be able to aff ord expensive modern medical therapy, so they refused to go.

Very few of the papers has unleashed that there is the phenomenal increase in the use of TOMs over last two decades but however there is no logical and scientifi c deduction of the fact. If the use of TOMs has not been substantially reasonable, then there must be some unidentifi ed underlying factors those may promote the use of TOMs. Secondarily, with the increasing literacy rate worldwide, one may presume as how come such beliefs and practices prevail. Alternatively, the resort to patronage of TOMs has been variously

attributed to ignorance, barriers to access primary eye care services, preference, failure of conventional treatment, desire to take control over medical treatment, communication gap between patients and orthodox eye care providers, and infl uence of friends and relations.

Traditional Ocular Medications (TOMs) are a form of biologically-based therapies or practices that are instilled or applied to the eye or administered orally to achieve a desired ocular therapeutic eff ect. TOMs are crude or partially processed organic (plant and animal products) or in-organic (chemical substances) agents or remedies that are procured from either a traditional medicine practitioner-TMP (Synonyms: Traditional alternative Medicine Practitioner-TAMP; Traditional Healer-TH, Spiritual Healer) or non-traditional medicine practitioners which could be the patient, relation, or friend. The use of TOMs, either as sole fi rst line treatment, or as adjunct used concurrently with conventional therapy has been associated with poor visual, ocular, and occasionally survival outcome of otherwise treatable eye diseases in clinical ophthalmic practice. TOMs- related poor ophthalmic treatment outcomes have been attributed to delay in uptake of eye care services while on fi rst line TOMs therapy; damage to ocular and or adnexal structures from intrinsic TOMs toxicity or result of interaction with prescribed medications, and microbial contamination of TOMs agent or procedure. The lack of standardization of dosage, low purity level, and non-physiologic physico-chemical properties of TOMs, and its unintended role as culture medium for pathogens account for the observed adverse eff ects.

TOMs use refl ects the diverse eye health care needs of the population not met by the existing

Adhikary RabindraReiyukai Eiko Masunaga Eye Hospital, Banepa

Traditional Beliefs in the Eye Care in Nepal

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eye care delivery system. Consequently, to eff ectively rein in the tendency to use TOMs, there is the need to understand the health behavior, health literacy status, socio-economic variables, and dimensions of barrier to access eye care in the population. The use of TOMs persisted for eons and no one can take a giant step to eradicate it at once. It is something that has become a part of the society for a long time. It helped (presumably) people from long before various orthodox medicines arrived. So, we can’t underestimate it when we have got better choices now. The rather progressive approach to eliminate it might be fi rst to upgrade the quality and service delivery system of TOMs providing trainings to the practitioners, educating and counseling them. Gradually, collaborating them to Governmental health posts or sub-health posts to encourage for the practice of modern service would be helpful. When the traditional practitioners start practicing modern and reliable medicines then they themselves counsel the society about its better and quicker advantages. Change is always possible but not abruptly, hence we can wait some more time longer to see the eff ects.

It is reasonable to illustrate some common beliefs of Nepalese people over the eye conditions and its traditional treatment modalities. Most often all the children are applied with the gajal or kajal (combination of soot or oil) soon after they are born. Gajals are supposed to strengthen the eye sight and cure red eyes. Some of them are preserved with the

antibiotic ointments, usually chloramphenical found in the aplicaps. There is no convincing scientifi c truth as to do any help to eye from its application other than the cosmetic enhancement. Since the ointment also remains outside the closed vial/pack for over months its effi cacy for the control of infection is again in question. In some regions Laal Gedi (Ipomoca gnomoclita ) is inserted into the conjunctival cul-de-sac for cleaning or removing foreign bodies. When one cannot take out the Laal gedi from the fornix then there would be formation of foreign body granuloma, disregarding the micro-trauma it may cause. Some use mothers’ milk in to the babies’ eye when there is some apparent problems like redness. Although the actual outcome is not completely understood one should be aware of practicing it after adequately cleaning breasts. When people have swollen lids (stye or chalazion), they believe when their lids are touched with the penis of a kid, then they are freed from such problems for ever. This practice may give arise further problem than solving it. Further, the folklore of getting styes in the eyes of liars is groundless to science as well. There are also extant practices of putting various herbal drops and gulaab paani (preparation from the rose petals and water) into the eye, as the composition and purity diff er with each preparation and possible contamination render this practice unreliable and insalubrious.

(The author declares that he has no competing interests.)


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Optometry profession is primarily interested in preventing the visual problems and enhancing visual skills so that, people can perform their jobs easier, faster and with greater accuracy. Lenses are used primarily as a means to prevent visual distortion and to stabilize adequate visual pattern.

Visual analysis is important in each and every cases of optometry practice. Visual analysis is a part of scientifi c optometry. It is a procedure of summing up optometric analysis for purpose of early decision regarding the proper rehabilitation procedure to follow in any particular case. It helps us to fi nd out the limitation of the prescript able lens for distance and near, whether the case can be solve by lens application alone, by vision training alone or by application of both vision training and lenses. It also helps us to follow the changes in relationship between accommodation and convergence brought about by the new lenses or the vision training.

From the point of view of visual analysis refractive error is not the cause of visual diffi culties. But a change in the habitual learned pattern of accommodation. Never prescribed a lens greater than the amount of accommodation free of association with convergence. This is the basic foundation of functional optometry. If the lens value we prescribed do not aggravate the existing problems they will be acceptable. This lens value is the subjective at far. For example if a one diopters hyperope without previous correction comes to you without any visual problem then it suggest that he has learned certain freedom between the accommodation and convergence equal to his refractive error. He has created fusional convergence at far equal in amount to the accommodative- convergence stimulated by the accommodation. There is always a habitual pattern between accommodation and convergence, we should keep it in mind that

the habitual pattern should not be disturbed by the new lenses.

In ancient time of optometry practice, optometrist used to refract for the distance and do subjective for the distance. They prescribe these lenses for constant use. But torch has been focused on the problem caused by the Contact lenses and spectacles we prescribe for distance. If the patient use it for near which is not supposed to be with the distance lenses, the patient will have various problems. Generally these type of problems are occurs in age group btw 10-40yrs of age.

The Minimum spherical diopters acceptance at near depend on the positive relative accommodation, negative relative accommodation, positive relative convergence and negative relative convergence. By looking at the Dissociated cross cylinder and Binocular cross cylinder fi ndings of near with a cross grid target, we can say the prescribed lens is correct or not for near also. Never prescribed a lens, which reverse the equilibrium pattern fi ndings (Blur out test at near). The blur fi ndings measure the ability of the organism to inhibit one component. Therefore, the relative relationship between these blur fi ndings indicates the direction in which the greatest degree of fl exibility exists. If the lenses change these relationships, visual diffi culty would ensue. Every patient should be counseled for the spectacles we give them, what is the purpose of it? Constant use, occasional use, for near only, for distance only or for both distance and near.

Visual analysis is very important aspect of optometry practice which can help us to improve our practice as well as in our legal issues. Visual analysis is purely optometry function which is entertained throughout the world.

Suraj UpadhyayaOptometrist, B.Optom (IOM) (TU)

Visual Analysis

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Abstract

Optometry, as an evolving Profession, has two possible directions it can take. Follow the way of conventional medicine, where the primary care model is to treat the symptom of the problem. This approach considers the absence of symptom being good health. The second possibility, is to recognize the real origin of disease and eye problems. A human being that is out of balance. Not only in their physical life, but their emotional and spiritual one too.

This paper draws on 40 years of clinical experience of a vision therapy oriented practitioner, one who has embraced the grandfather principles of functional and behavioral vision concepts. A modern approach that recognizes a new paradigm of vision care that has been born. Can this integrated model be embraced as a second 'upgraded’ direction for Optometry? Like in biblical times, there are commandments that show the way to enlightenment. These could be the steps to go beyond a symptom based medical model of treatment. An approach that is Holistic in its foundation, and redirects the responsibility for healthy eyes back to the patient.

Introduction

Raised and educated in South Africa, forty years ago I began my career seeing patients as an Optometrist. This was my fi rst and only career choice. To guide people towards healthy seeing. My teachers and colleagues emphasized looking at the whole person when designing a vision care program. There was little interest in being a ‘Junior Ophthalmologist', only treating the eye problem!

From the beginning, I thrived on the concepts

of Functional and Behavioral Vision Care. In spite of my fi rst practice experience being mostly prescribing glasses, each day, I explored the visual fi ndings and considered home based vision training principles for the patient. This was my way of exploring the relationship between the human being and what their deeper perceptual ‘seeing’ was communicating to me through my vision analysis fi ndings. At fi rst, I had no real skill in communicating this Holistic way of dealing with eye problems. Over the years I was able to simplify my communication, such that more patients involved themselves in the integrated Vision therapy. In this way, I conducted my own clinical trials.

This paper is a result of this process and also includes my 16 year Professorship and clinical research at two Colleges of Optometry in the United States of America. During this time I have observed our profession being politically infl uenced and pressured to fi t into an outdated health care model. One that is driven by the Pharmaceutical and Eye and Contact Lens manufacturers. That is, our vision care delivery is infl uenced by industry and politics, rather than conscious Holistic health care practice. Even today, there are Optometrists being sucked into being like their medical counterparts, where treating eye disease is the focus. What about good old Functional and Behavioral Approaches. Where the well-being of the patient comes fi rst. An approach that has prevention and regeneration at its heart. The standard Optometric model is for the practitioner to treat disease and eye problems in a standard symptom based approach. It's an easy model to follow, when the patient is unwilling to take self responsibility for their visual well-being.

The 10 Commandments for the Future of Optometry

Roberto Kaplan O.D., M.Ed., FCOVD.

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However, the ever growing presence of the Internet in people's lives is accelerating the interest in self-help approaches to health in the U.S. and other countries. Consumer desire for organic and healthy food and complementary healing methods is becoming standard practice. There is easy availability of information via the Internet for the public on alternative and complimentary ways to help their eyes. This opens up the possibility for us as Optometrists to provide a healthy therapeutic form of vision care. Our Optometric Profession must take a stand for the future - Prevention. If we don't, we will always be subservient to Medicine and Ophthalmology.

For an eff ective paradigm shift to occur there needs to be a vision, and a blueprint for steering the direction. The branch of Optometry that evolved on the Functional and Behavioral principles of Skeffi ngton, archived through the Optometric Extension Foundation, can serve as a beginning point.

The 10 Commandments is a modern extension of these clinical methods, with an upgrade for the complex virtual world and technological time we live in. Primary Care Optometry, modeled after conventional medicine, is not eff ectively controlling the ever increasing rise of refractive and eye disease problems.

Within these 10 Commandments is the solution. The growing numbers of people interested and committed to a preventive approach to vision care is our opportunity. The clinical know-how is available. It is time for Optometrists to upgrade their model of vision care to bring this possibility into reality. The 10 commandments serve this purpose.

What are the 10 Commandments?

The commandments speak to the wisdom of a functional approach in dealing with patient's vision problems. My patients, by identifying their personal needs taught and directed me to the 'know how'? The commandments speak less to a technique or method of use, but more to the way of how to be with the patient. To see their eye problems as part of a

continuum of their life struggles and evolution. My eyes were opened to see the eye problem as an entry point to the human being's way of perceiving themselves more deeply. In this way, they were more able to perceive their life problems from a holistic perspective. This paper is a way to present these discoveries as an introduction to the future. A way for Optometry to steer its direction to a truly preventive profession, much like Dentistry has accomplished. Obviously, to administer this approach in a clinical setting will take additional study and practice.

Here are the 10 Commandments:

Commandment 1 - Treat the human who sees not with the eye, but through the eye

There is a scientifi c myth, that has been heavily conditioned into the thinking of both practitioners and the public alike. We see with the eyes. Light comes into the eye, it is refracted and an upside down image forms on the retina. From a physical point of view this may be stated so. However, from a psychological perceptual and quantum physics point of view, a revised understanding is necessary.

Light does enter the eye. This light is transformed by refraction. The upgrade in thinking is that the light carries information. It is not the light per say that we are interested in. It is the invisible information with in the light that provides the impetus for perception. It is perception that ultimately determines how and what we see. When the upside down information is correctly received and processed through the brain, an accurate perception is formed. Note, I stated through, not in the brain.

However, there are many variables that can interfere in this processing ability. The main one is the inner state of the person themselves. What exactly is meant by this statement. Recent breakthroughs in understanding the 'Biology of Consciousness' helps point the way. . How receptive the tissue and structures of the eye is to the incoming light is dependent on how


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present or aware the person is behind the eye. From Brain research one could hypothesize that it is simply a matter of the person's focus and attention that is needed for the retina and macular to receive the light. If this happens, then the assumption is that the light is transmitted. New evidence suggests that it is not so simple. There are actually two primary variables that aff ect the functionality of the eyes. One certainly is the brain. A very helpful part, since its primary role is to protect and help the human survive. Survival mechanisms can steer the energy to and through the eye, and we can react very quickly.

New evidence from 'Monk's Brain' studies reveal another phenomenon. Lamas who are trained in mind\spirit matters, like meditation, are more able, and far quicker, able to activate larger surface areas of brain tissue. The resultant eff ect is that they can process light through the eye in a much more complex way, such as in hidden computer driven stereoscopic images. This still 'brain state' gives them the ability to see more deeply into themselves and life, with less eff ort and time. Their visual performance far exceeds that of Western intellectual counterparts.

Commandment 2 - How the patient sees, and what we measure in the eye, is a refl ection of their perceptions

Seeing is promoted as being primarily an eye function is now a belief in normal eye medicine. Few consider that in the total process of vision, the eye probably only contributes about 10 percent. The brain and the human spirit determines how and what is seen. So, when an abnormality is measured in the eye, such as Myopia, Astigmatism, suppressions, Glaucoma etc., the source of the problem is behind the eye. My clinical fi ndings implicate that what we measure at the level of the eye are misperceptions, actually survival perceptions, that get programmed into the eye via the nerves and blood supply.

So, this means in vision therapy we are providing experiences to reorganize a very deep inner process. It is not enough to just

treat a measured coded abnormality, like a convergence insuffi ciency or strabismus, that is even classifi ed as an eye disease. Vision therapy is more than what is accomplished in the training room. The procedures the patient is following must be practiced in their real life, at home. If vision therapy is modifying perception, then the resulting experiences must have a place to land in their personal life. Usually, we think of vision therapy as training certain eye and vision skills that eff ect reading, working at a computer, learning and in sports. At the very core of not seeing is avoidance. The resistance to see issues or problems in patient's lives can and does show up as measurements of refractive and eye conditions. In the same way, if new healthy perceptions are encoded during the vision therapy process, then the Myopic and Astigmatic perceptions are modifi ed. This can actually be monitored through changes in visual acuity, binocularity, and over time lowered and modifi ed diopter measurements.

If these perceptions are more healthy, then this new way of seeing can also benefi t how the patient sees their choice of career, relationships, family and lifestyle. To take this one step further, clear perceptions directly impact personal problems in patient's lives. Intimacy, deep connection, and addictions are positively aff ected by vision therapy.

Commandment 3 - Do not treat or try and fi x the diopters, suppressions, lack of visual acuity, eye diseases, phorias, and other eye fi ndings. Use them to defi ne what the eye is communicating about deeper perceptions of the person's whole existence

It is a very big step for a practitioner schooled in Optometric and Medical Science to modify their own inner perceptions of the reality they have been conditioned to believe. We are trained to diagnose eye problems and provide treatments. This model is predicated upon the belief that if we measure something in the eye, that deviates from a norm, the eye condition is the problem that has to be fi xed. The future of Optometry being a truly preventive


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discipline, needs a new perception of the eye measurements and what to do about this so called 'problem'.

Consider that our usual eye measurements, and their relationships to the patient's symptoms, are a print-out and communication from the brain. This communication is a ‘call out’ for help. It is not an eye problem. The brain makes adjustments to its vascular and neural messaging to the eyes when it's in a survival state. This messaging implicates the presence of a survival perceptions, like fear or anger. The most vivid demonstration of this process is the case of retinoscopy. A young patients sees perfect 20/20, and yet the retinoscopy fi nding already showing a minus projection. The eyeball is fi ne at this stage, however, the retinoscopy is showing a survival restrictive perception. Our usual treatment strategy is to tell the patient to come in the future. Then when the eye shows the Myopia, we can 'correct' it with minus lenses.

Then the question can be asked, "What exactly does our lens and vision therapies provide for the patient?" In conventional primary vision care our "correct the refractive error" model locks the patients perceptions into the survival mode. Compensation is just covering up the symptoms not correcting anything. Except, perhaps preventing the practitioner and patient from dealing with the fear of lowered visual acuity. What this means is that the healthy perceptions of thinking, feeling and emotions are not given the appropriate chance to gain the necessary developmental steps for integration. It could be stated that an eye suppression is a one sided suppression of thinking, feeling or emotional perceptions. Psychiatrist Frederick Schiff er, has identifi ed localized areas of emotional activity related to light coming through one eye. So in vision therapy we are guiding the patient into perceptual experiences of higher and higher levels of fusion or integration of the brain. However, this is still only a stepping stone towards a human experience through the eye that is akin to a visionary meditative state, like the Lama Monks have demonstrated. This still

state of seeing gives the freedom to deal with life problems from a less reactive position. Less terror, wars, anger and a return to honoring the unity of the human family on this Earth.

Commandment 4 - Prescribe glasses that are preventive and therapeutic because the ‘correct the refractive error’ glasses do not correct anything

Normal lens prescribing follows the correct the refractive error model of vision care. The measurement in and of the eye is an eye problem, and that is the end of the story. Write the prescription for 20/20 and get the next patient in. We have a new commandment. There are patients who come in to our offi ces interested in taking more responsibility for their visual well-being. This means that we are needing to upgrade our prescribing approaches to meet this level of consumer interest. The growing interest in corrective surgery, like Lasik, is raising the awareness of the possibility for improving vision. Not just functional vision skills, but also visual acuity. Growing numbers of patients are investigating natural approaches to lowering their dependency upon strong glasses. What is our position in Optometry on this obvious marketing opportunity. One that can serve the profession of Optometry, but more important, help vast number of patients lead a more conscious life through healthier functioning visual systems. At the core of a new form of lens prescribing is the premise that the visual system is a natural biofeedback system. The interaction between the fovea/macula and retinal input sets the stage for clearness and unclearness of sight. A normal correct the error lens neutralizes the unclearness of perception into an over focused fovea focus. This introduces a perceptual experience for the patient to fear unclearness and label it wrong. We, as Optometrists, even reinforce this way of thinking. Everybody has to have a sharp focus and be clear, otherwise it is dangerous for them. On the other hand, an integrated vision therapy model of lens prescribing has been birthed and clinically tested for over 30 years. That is, for the self responsible patient


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(this is emphasized), especially the Myopic patient, provide a reduced lens prescription. In this way, a clear and unclear fovea/retinal relationship is established.

What happens next is where the real patient compliance and self motivation comes into play. The patient is coached to become aware of what circumstances in their life produces changes in visual acuity. That is, when does the visual acuity seem less clear and visa versa, when does it increase. Variables like certain foods, fatigue, excessive computer use, and spending time outside produces changes in visual acuity. The main advantage of this lens form of integrated vision therapy is that the patient begins monitoring their own vision. They learn very quickly that their eyesight and perception is under their control. Then the Optometrist becomes the teacher, the guide to true prevention. There is no need to fear that glasses will become obsolete in this model. The opposite is true. Patients will be prescribed more lenses for use in the diff erent parts of their lives.

Commandment 5 - Prescribe minus lenses in the direction of a parasympathetic stimulant (less minus and more plus), since minus lenses that compensate for 20/20, or 100% eyesight, are a sympathetic stimulant, a drug.

It is not very often that we are given a chance to refl ect that a lens acts like its prescription drug, that is it has a direct pharmacological action on the autonomic nervous system. The fi fth commandment is each time a new minus lens prescription is written, REMEMBER, you are ordering the patient to look through glasses that is a stimulant, like ‘speed’. Yes, you are sharpening visual acuity and giving them a chance to protect themselves from not seeing unclear on a physical level. At the same time you are locking them into survival perceptions of their inner unclearness. This is like supporting an addictive process of not becoming aware. The emerging integrated model of vision care supports the patient in looking at their ‘drugged’ way of perceiving. To help them look through lenses that wake up

their perceptual consciousness. All inhabitants of our planet Earth need to see themselves and outside in order to restore the survival way we are living. It begins with our perceptions. As Optometrists, we have a big role to play in the future scenario of people seeing correctly through their eyes. For the Myopic population, lowered minus lens prescriptions introduces a relaxed parasympathetic way of looking. Through the retinal stimulation, having more feeling for what we are looking at is awakened. This feeling over time is called compassion. The logical clear view is softened. Slowly, as the patient lives this way of looking and seeing, so the brain and eye adjust. We measure this more balanced state in the refractive and binocular fi ndings. Prevention is started for the patient and their off spring.

Commandment 6 - Prescribe glasses, with an integrated vision therapy approach, thus giving the patient the self responsibility for their vision future

While considering this therapeutic way of prescribing, it will be necessary for most patients to be educated about returning for regular visits. In actual fact, the patient can be guided to realize that in offi ce supervision, say once per month, will be supportive for their new commitment to prevention and regeneration. This approach serves to maintain a high level of self responsibility. Once the patient makes the decision for regular monthly visits, their integrated vision therapy involvement in their life is more likely to happen. In offi ce visits, can include introduction to conventional vision therapy techniques, however, these visits serve another very important process. It is a chance for the patient to experience the deeper connection between their life processes and change in perceptions. The functional Optometric fi ndings of refractive status, like astigmatism, suppressions, and fusion will refl ect what is happening to the patient’s inner world of perception. In my offi ce sessions, I show the patient these connections and how by using their new perceptions in their life, the measurements in the eyes change. The main variable to monitor is visual acuity in the


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distance. The second is the level of binocular vision. These fi ndings vary according to the perceptual level of presence and awareness of the patient. If they need to block a certain life experience, there will be lower visual acuity, or they will suppress the view through one eye.

Commandment 7 - Observe and learn how every eye condition of refraction or disease is a view into how the patient is deviating from their fundamental perceptual EyeCode®. (That is their God given way of perceiving)

Every condition or variation that we measure at the level of the eye is a refl ection of an avoidance of perception in the inside world of the patient. The patient is genetically coded with information, like phorias, structures on the iris, and fusion abilities. Each person has unique astigmatic axes. One can consider that these fi ndings serve as blueprint for an individual EyeCode®. Over the years, I have categorized these codes into what has become known as the Kaplan EyeCode®. The Iris EyeCode® shows the fundamental core perceptual style of the patient, either a logical, feeler or emotional processor. In addition, there is precise information, called perceptual infl uences, that are passed down from the parents. This forms the basis for the patient to deviate from their core code. The Diopter and Disease EyeCode® reveal the deviations from the core perceptions that are related to life conditioning. These are the environmental conditions that begin after birth. For example, a child may have genetic infl uences to show Myopic measurements at the level of the eye, and the interaction with the Myopic parents and fi tting into a Myopic conditioned society then exaggerates their moving into Myopia at a faster rate. On the other hand, a patient with no genetic Myopic infl uences, has less impetus for Myopic perceptions and development for a Myopic eye. They may however, trigger a Myopic visual style by environmental abuse of their visual system, such as in excessive computer use. In the same way, certain perceptual states, like self imposed pressure, either inherited or learned, can be connected to elevated levels of intra ocular pressure. My

fi ndings suggest that when the patient fi nds out about this inner and outer connection, they are more motivated to take self responsibility for their eye problems. This is a big relief for us, the practitioner, to have a patient take charge. Our true role in vision care becomes evident. We are then the coach, mentor or guide to the patient opening up to their vision.

Commandment 8 - Consider all treatments for eyes to be connected to where the patient is in their life cycle, that is, the variables before their current chronological age, and the future.

Is it possible, that the within the Biological workings of the eyes are changes that show up during diff erent periods of our cycle of life? Clinically, I have observed that as we go through life in 20 year cycles, there is a repeating of certain perceptual experiences. It seems that our perceptions of thinking, feeling and emotions are given repetitive chances to evolve themselves. At the same time, the code of the eye, reveals changes, for example Presbyopia. Normally, we say the change of lens and ciliary muscle fl exibility is just due to the aging process. Consider that Presbyopia is part of a Biological imperative that is designed to modify thinking perceptions into more feeling and emotional forms. This would make total sense when one’s considers the life cycle of when Presbyopia begins. The patient’s foundation of their life has been concretely built. Usually the career, home and family is established. Now it is time to feel and enjoy life more. Less need to focus and gain knowledge and more time to feel and be touched by life itself. The implication of this is huge. Preventive and life cycle lens prescribing will then take on a very diff erent form than treating the patient as having something wrong with their eyes. The eye condition and the patients age guide us to prescribe lenses that will support the patient’s life process rather than just giving them false sense of sharpness of eyesight such they can continue being unconscious of their fears or need to evolve.

Commandment 9 - Examine the eye and


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visual fi ndings to reveal how well the patient is integrating their perceptions of thinking, feeling and emotion.

The visual fi ndings follow a coded perceptual developmental path in addition to the environmental conditioning. Evolvement of inner vision is a life process of integrating perceptions of thinking, feeling and emotion. The anatomy of the eye is the fi rst place to observe this fact. The macula is designed to gather focused light in the fastest way possible. The precise information within this focused light is used to build an understanding known as the content of life. The retinal unfocused light, is slower in being processed by the brain. This information forms the context of what is looked at. This feeling state supports our perceptual processes of being touched, the beginning basis for healthy emotional states. During the life cycle these perceptual states integrated to deeper and deeper levels. Of course, the success of this integration is what we measure as the state of fusion between the two eyed inputs. Clinically, I have observed that many patients under life and visual stress lose the ability to keep this integrated Binocular status of multidimensional vision. If the perceptual state gets stuck in either thinking, feeling or even emotion, a survival state of vision is cemented. This limits the capacity for the eye to receive light and sets up the patient for a lack of fulfi llment in their life. Modifi cation of the perceptual state through integrative vision therapy encoding, frees up the natural progression once more. The patient can be guided how to integrate these three levels of perception, preparing them for a future preventing further destruction of eye tissue.

Commandment 10 - The vision care program must address the reality that at the very core of measured vision problems is an inability for the patient to handle emotional incongruity.

One of the most diffi cult future steps for the profession of Optometry to take is to recognize and acknowledge that at the very core of measured vision problems is an inability for

the patient to handle emotional incongruity. The implication of this statement is vast. The alterations of the eyeball length, power, and the tissue changes we see extend beyond just the physical. Biological changes at the level of the eye are printouts of survival nature of the human beings brain state. The good news is that through re-traveling the journey of thinking, feeling and emotional perceptions, the survival perceptions can be encoded into a healthy pure view. This higher frequency state can be considered to be a kind of essential seeing, like a spiritual view. Certainly, the brain and mind state investigations of the Monk’s brain testify to this possibility. Is it possible that in primary care Optometry we are missing out on this vast potential we have in our profession? Is our physically oriented vision therapy only just scratching the surface of the potential we can off er patients? My experience of the higher levels of integrated vision therapy has provided me with a deeply fulfi lling career as an Optometrist. I off er these commandments to our profession. Upgrade now, it is time and there is a brilliant possibility.

Roberto Kaplan is a Doctor of Optometry with an interdisciplinary Master’s Degree in Visual Science, Special Education, Speech Pathology and Psychology. He has been Board Certifi ed in Vision Therapy for 36 years. Retired from normal Optometric Practise, Dr. Kaplan collaborates with Medical Doctors, Optometrists and other Professionals in varying approaches to Psychosomatic and natural Holistic steps to Health and Vision Care. www.robertokaplan.com


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The World Health Organisation (WHO) has a programme to fi nd ways to prevent and elimi-nate blindness around the world by the year 2020 – ‘Vision 2020’.

Visual impairment causes not only suff ering for an individual person but the economic im-pact on society as a whole is enormous. Eyes are the major sense organs for human beings and any defect in them can contribute to other health and mobility problems. Not only is the world population expanding quite rapidly but the average life expectancy is also moving up causing many challenges.

Cataract, glaucoma, diabetic retinopathy, cor-neal injuries and uncorrected refractive errors are the most common conditions. If sight is causing one or more of these conditions, what needs to be done? What can be done? It’s a huge problem now; it will be bigger in the fu-ture.

Suff ering aside, the partially-sighted person is dependent on family or friends for daily help.That may mean the helper must forgo their own education or paid occupation. The eco-nomic cost to them and the family is great. Of-ten the visually-impaired person cannot pre-pare meals, help in the garden, wash clothes, or even identify friends and family. Studies have shown that there is a strong association between depression and the quality of life, and an increase in mortality in these people. Glaucoma suff erers have, for example, a great risk factor for falls because they may have suf-fered a loss in their lower visual fi eld and a de-crease in their contrast sensitivity.

It is imperative that governments are aware of the costs that blindness is causing and that they make an eff ort to fund a blindness pre-vention programme.Uncorrected refractive errors are the leading cause of visual impairment all over the world

and could be costing billions of dollars a year.The majority of these problems are in develop-ing countries where there is a signifi cant lack of trained personnel, and a fi nancial problem. However these issues are not only in less eco-nomically developed countries but are com-mon throughout the world.An example is myopia. There has been a marked increase in this refractive condition of late.The cause is thought to be not only genetic but associated with the amount of close work undertaken in childhood and youth. There is a good deal of research work being undertaken to fi nd the reason for this and to eventually prevent this nuisance condition.

On the positive side, the treatment of some eye conditions has improved dramatically over the last fi fty years, and they have become relative-ly less expensive. Even though the cost of the procedures may seem large it is small when we take into consideration the terrible problems we would have to endure without them. New and inexpensive instruments are becoming available which will help in the detection and diagnosis of glaucoma and maculopathy.They are really clever and small and can be at-tached to iPhones where the information can be saved, printed and emailed.

Make no mistake - we are all greatly needed, and appreciated.

Eliminating World BlindnessBob Kinnear

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There is a growing numberof Neuro-Developmental Optometrists in the United States that are using Visual Evoked Potential (VEP) as a tool to diagnose and choose proper treatment protocols. When I was a student in the mid-1980’s, VEP was an instrument mostly relegated to the Optometry schools. Advances in computer technology and the testing methodology over the last ten years have made this a very viable tool.

Visual Evoked Potentials are electrical signals that are measured from the electophysiological activity at the visual cortex. VEP’s occur when a patient observes a visual stimulus such as a fl ashing checkerboard, a sinusoidal grating or even a fl ash of light. The results are a representation of the functional integrity of all levels of the visual pathway including the retina, optic nerve, optic radiations and visual cortex.

VEP testing is purely objective and does not require the patient to do anything beside look at the pattern on the screen. Patterns can be both high contrast (testing primarily the parvocellular pathway) or low contrast (testing the magnocellular pathway). Because

of the nature of the testing, one can easily test patients that are preverbal or non-verbal and even infants. In addition, we can objectively measure the patient’s responses to our treatment protocols (lenses, prisms, patching, bi-nasal occlusion and vision therapy). Furthermore, testing is repeatable and can measure clinical success over a time period.

Other applications of VEP just being released are in the diagnosis and treatment of Glaucoma. Testing is also benefi cial in patients with systemic neurological disorders such as Multiple Sclerosis.

Many of us are working together to develop new testing protocols. A user group met at the Neuro-Optometric Rehabilitation Association (NORA) meeting this past spring in Memphis, Tennessee, USA. The goal of this users group is to share and standardize protocols over the next few years so that comparative data can be shared and new uses of the instrumentation may evolve. As new protocols develop and testing is further refi ned, I expect the use of Visual Evoked Potential to increase signifi cantly not only here in the USA but all over the world.

The Use of Visual Evoked Potentials (VEP)In the Optometric Practice

Charles Shidlofsky, O.D., FCOVDPlano, Texas USA

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The four o’clock hour arrives at the offi ce of Vision Therapy Group in Flint, Michigan (USA). Three vision therapists emerge from their offi ces and head into the therapy room to meet their patients. The patients, many of them children, generally attend vision therapy sessions during the hours immediately after school. They have come for a variety of reasons, but mostly they are searching for explanation as to why they struggle in school and are failing to live up to their full potential. The clinic is administered by Doctor Bradley Habermehl, immediate past president for the College of Optometrists in Vision Development. Dr. Habermehl has been an optometrist for over 23 years off ering optical and contact lens services as well as specialized treatments for those struggling with learning and behavioral issues on the autism spectrum. He and his staff of trained therapists have been helping students who struggle in school with reading and comprehension, and those who struggle with a lazy or wondering eye for nearly 18 years.

In the United States, vision therapy sessions generally run for 45 minutes to 1 hour, depending on the practice. Patients work one on one with a therapist to correct a variety of functional visual issues. Treatment can involve a variety of activities and exercises that encompass everything from balance boards and tracking sheets, to prisms and metronomes. The most common diagnosis is convergence insuffi ciency. This condition often leads to diffi culties with reading comprehension, visual memory, and depth perception. Patients with convergence insuffi ciency often report that they see double or “ghost” images or that the words appear to jump around on the page. As a result, these patients tend to struggle in their studies and can turn to negative classroom

behavior in order to avoid reading, writing, or doing math.

Other patients seek out vision therapy for help with strabismus and amblyopia. Often, these patients have sought help from numerous doctors and specialists. It is not uncommon for patients with strabismus to turn to vision therapy after several failed surgeries to correct an eye turn. Vision therapy teaches the brain to use and interpret information from both eyes, negating the need for a compensatory eye turn.

Many patients, who suff er from visual motor diffi culties, also suff er from poor body awareness and a compromised vestibular system. Therefore, it is frequently necessary for patients to receive treatment for these areas before beginning ocular motor work. Vision therapy treats the whole person and since the visual system does not function independently of other systems, all related motor defi ciencies must be addressed as well.

Very often, patients who have been previously misdiagnosed with ADD, ADHD, dyslexia, and even autism spectrum disorders, can fi nd help in the optometrist’s offi ce with vision therapy. Doctors who specialize in vision therapy, developmental optometrists, receive their board certifi cation from the College of Optometrists in Vision Development (COVD). The international offi ce of COVD is also responsible for ongoing training and certifi cation of certifi ed vision therapists (COVTs).

Those interested in learning more about vision therapy should contact the College of Optometrists in Vision Development (COVD) at www.covd.org or the Optometric Extension Program at www.oepf.org .

Changing Lives with Vision Therapy

Ruth Villeneuve Vision Therapist)

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Hyphema is not a common occurrence and it is even more uncommon to see hyphema in the presence of past radial keratotomy (RK). With the onset of laser refractive surgery, the popularity of RK has plummeted signifi cantly. Although less common today, a form of form of radial keratotomy called “relaxing incision” is used during cataract extraction to alter re-fractive error to stabilize vision.To see hyphe-ma (bleeding into the anterior chamber of the eye) is a serious clinical entity and may re-quire urgent evaluation. Presenting hyphema can alarm the examiner and in the presence of RK scars, even create consternation about compromise of the globe, anterior uveitis and glaucoma. John and Schmitt (1983) reports seven cases of coincidental hyphema and RK without any perforation.The management of a patient with hyphema can be found in Shep-pard’s (2011) post at Medscape. As Sheppard states the most commonly seen traumatic hy-phema is one that only fi lls about one-third (“1/3”) of the anterior chamber as in the photo below. In fact studies show that nearly 60% of hyphemas involve less than a one-third of the anterior chamber.Here are some key clinical implications. The fi rst is increased intraocular pressure (IOP). Up to 32% (Sheppard, 2011) will have some elevation in IOP. A consistent el-evation of IOP can be found in hyphemas that are almost 75-90% of the anterior chamber. Monitoring the IOP on a daily basis is prudent.The second most common entity is to watch for “rebleeds” (secondary hemorrhages). Re-bleeds may occur more often in African Ameri-cans than in white patients (Sheppard, 2011). There is speculation that sickle cell trait can be uncovered by a hyphema. Monitoring these patients on a daily basis may not improve the outcome because most rebleeds do not occur until the third or fourth day of the trauma. Re-bleeds, if they do occur, do worsen the prog-nosis for a normal eye.Lastly, hyphema can be stimulated by the use of certain non-steroidal anti-infl ammatory medications (NSAIDs). Their use can actually stimulate a spontaneous hy-

phema or even a rebleed. Because a rebleed is likely to produce a more serious outcome from the hyphema and is to be avoided, the patient should discontinue the use of anti-platelet, anit-coagulant and NSAIDs or until the pa-tient’s personal physician can be contacted.In summary hyphema in the presence of past RK is likely to have no diff erence in outcome than an eye who has never had hyphema. In most cases,hyphema is self-limiting and requires monitoring IOP, uveitis and rebleeds. Radial Keratotomy HyphemaBloom HR, Sands J, Schneider D. Corneal rup-ture from blunt trauma 22 months after radial keratotomy. Refract Corneal Surg. 1990 May-Jun;6(3):197-9.Elgin U, Sen E, Teke MY, Tirhis H, Ozturk F., Mi-crotrauma-induced recurrent hyphema and secondary glaucoma associated with chronic acetylsalicylic acid use. Int Ophthalmol. 2012 Feb;32(1):89-92. Epub 2012 Feb 2.Jean D, Detry-Morel M. Stellar corneal rupture and secondary glaucoma after squash trauma in a keratotomized eye. Bull Soc Belge Ophtal-mol. 1992;245:109-13.John ME Jr, Schmitt TE. Traumatic hyphema af-ter radial keratotomy. Ann Ophthalmol. 1983 Oct;15(10):930-2.McKnight SJ, Fitz J, Giangiacomo J. Corneal rupture following radial keratotomy in cats subjected to BB gun injury. Ophthalmic Surg. 1988 Mar;19(3):165-7.Sheppard, J.D. “Hyphema” Medscape refer-ence web site. March 9, 2011. Available on-line at http://emedicine.medscape.com/article/1190165-overview. Retrieved on 19 July 2012.Trivedi D, Newton JD, Mitra A, Puri P. A seri-ous drug interaction leading to spontaneous total hyphema. J Postgrad Med. 2010 Jan-Mar;56(1):46-7Disclaimer: These are the personal opinions of Dr. Hom. There are no disclosures for this post. © Copyright 2012 Richard Hom OD MPA aka “Tips4EyeDocs”

HYPHEMARichard Hom OD MPA

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High resolution optical imaging of objects hidden in scattering media such as the human eye is a challenging and important problem with many industrial and medical applications. Optical Coherence Tomography(OCT) fi rst described in 1991 (Huang 1991), used this type of system and was rapidly adopted for medical applications, especially for ophthalmic imaging. OCT allows for noninvasive in vivo cross-sectional imaging of ocular structures such as the retina, retinal nerve fi ber layer (RNFL), and the optic nerve head. It measures the intensity and echo time delay of back-scattered and back-refl ected light from the scanned tissues.

Spectral domain OCT (SD-OCT) is a newer technology based on Fourier transformation theorem which aff ords unprecedented ultrahigh resolution ultrahigh speed RNFL imaging. This technology is possible, because it uses a spectrometer that is a fundamentally a more effi cient way to process information coming back from the stationary reference mirror and the eye. The advantages of SD-OCT over Time Domain OCT include faster image acquisition, higher resolution, automated real time(ART) image averaging, TruTrack eye traking technology and much better Signal to Noise Ratio (SNR).

Spectralis OCT in Glaucoma – Image acquisitions and interpretations

RNFL circle scans

This consists of a 3.4 mm circular scan that is used to measure the thickness of the RNFL. A RNFL curve is obtained by ‘opening up’ the circular scan. The RNFL curve starts with the

temporal quadrant and continues clockwise in the right eye and counterclockwise in the left eye. The RNFL thickness values are provided for the four quadrants (temporal, superior, nasal, and inferior) and for 12 clock hours.

For OCT circle scans, the retinal nerve fi ber layer is automatically segmented and the RNFL thickness is measuresd along the scan. The thickness measurements are compared to a normative database. TruTrack active eye tracking and Automated Real Time (ART) imaging are now signifi cantly improved for the acquisition of circle scans. This results in faster image acquisition and considerably higher image quality of these scans. For the RNFL preset, the default for the number of images averaged with Art is now increased from 16 to 100 images, leading to improved image quality.

Thickness profi le graph

The normal retinal nerve fi bre layer thickness

Spectral Domain Optical Coherence Tomography in Glaucoma –

A review of its interpretation

Mr. Safal KhanalFinal year, B. Optometry

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graph shows a double hump pattern with thicker superior and inferior sectors and thinner nasal and temporal sectors. The graph in the lower right of the window shows the RNFL thickness profi le measured along the circular scan, and its comparision to the normal range. The black curve indicates the measired RNFL thickness. The green band represents the normal range of RNFL thickness(within normal limits), defi ned as the range between 5th and the 95th percentile of the normal distribution. The green within this normal band represents the mean RNFL thickness of the normal eyes. The red area denotes the range below the 1st

percentile of the RNFL thickness distribution in the normal eyes. A measurement value falling into this range is considered as ‘’outside normal limits”. The yellow band represents the values below the 5th percentile but above 1st percentile of the distribution of the normal values. A measurement value falling into this range is highlighted in a yellow color and is labeled as ‘borderline’ to indicate that it falls between these two percentiles of the normal database sample.

Classifi cation

The pie chart displays classifi cation results for the 6 sectors of the optical disc (T, TS, TI, N, NS, NI), together with a global classifi cation. The black value gives the average RNFL thickness measurement value for each sector and the

This is an OCT imaging report of RNFL of both eyes of a 52 year old Female diagnosed as Glau-coma suspect. The retinal thickness map in the Right eye looks normal since the black line lies in the green shaded area indicating it is within 95% Confi dence Interval(CI) of the normal pop-ulation. Similarly, the sectorial RNFL thickness is all shaded in green. In contrast, the RNFL thickness graph in the left eye lies in the yellow zone in the nasal re-gion and also the sectorial RNFL thickness is shaded in yellow in the nasal sector indicating the thickness is within 99% CI of normal popu-lation. Therefore, the OCT report of RE can be termed as “within normal limits” whereas that of left eye as “outside normal limits” as one or more sectors in yellow signifi es borderline clas-sifi cation.

Interpretation

Case –reports

Case- report 1


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global average (G). The green value below in brackets indicates the average value from the normative database adjusted to the age of the examined patient. If the measured average thickness in a sector is within the 95% confi dence interval of the normal distribution (p>.05), the sector is colored green to indicate it is within the normal range. If the average thickness is outside the 95% confi dence interval but within the 99% confi dence interval of the normal distribution (.01<p<.05), the sector is colored yellow to indicate borderline. If the average thickness is outside the 99% confi dence interval of the normal distribution (p<0.01), the sector is colored red, indicating

This is an OCT imaging report of RNFL of both eyes of a 72 year old male diagnosed as Pri-mary Open Angle Glaucoma. The retinal thick-ness graphs in both eyes appears to lie in the red shaded area in most regions. Similarly most of the sectorial RNFL thickness in both eyes are shaded in red signifying a greater amount of RNFL loss compared to normal population (less than 99% CI). Since the report is classifi ed abnormal if one or more sectors are shaded in red, the OCT imaging report of this patient in termed as “outside normal limits” in both eyes.

Interpretation

Case- report 2 outside normal limits. An outside normal limits classifi cation means that less than 1% (1 out of 100) of all normals from the database have thickness values this low, indicating a high probability of abnormality. The colored bar below the pie chart indicates the overall classifi cation. The bar is red ("outside normal limits") if one or more sectors or global is outside normal limits, and yellow ("borderline") if one or more sectors or global is classifi ed as borderline but none as outside normal limits. If all sectors and global are classifi ed as within normal limits, the bar will appear green ("within normal limits”).

RNFL progression report

This printout is dedicated to record the progression of RNFL thickness measurements for an individual patient. The examinations are listed chronologically decipting following elements.

• The OCT circle scan for each examination, shown with RNFL segmented.

• The comparision of each scan with the normative database including quantitative sector analysis.

• The RNFL thickness profi le on the right side indicating the changes in RNFL thickness with respect to the reference exam. Loss of RNFL is shown in red.

RNFL trend report with FoDi

This shows a trend diagram displaying the ratio of mean measured thickness and mean normal thickness of the normative data for each sector. The scale of horizontal axis can be set to time or ecamination number. A number of 1.00 indicates the average value of the normative database. Any sector values below 1.00 indicate that the sector is thinner than the average of the normative database while sector values greater than 1.00 indicate that the sector is thicker than the average of the normative database.

The Diff erence to Selected Reference Charts give the diff erence of every sector compared to the selected reference image that is outlined


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by a Red Box in the RNFL thickness area.

References:1. Budenz DL, Anderson DR, Varma R, Schuman J, Cantor

L, Savell J, et al. Determinants of normal retinal nerve fi ber layer thickness measured by Stratus OCT. Ophthalmology. 2007;114(6):1046-52.

2. Vizzeri G, Balasubramanian M, Bowd C, Weinreb RN, Medeiros FA, Zangwill LM. Spectral domain-optical coherence tomography to detect localized retinal nerve fi ber layer defects in glaucomatous eyes. Optics express. 2009;17(5):4004-18.

3. Moreno-Montanes J, Anton A, Olmo N, Bonet E, Alvarez A, Barrio-Barrio J, et al. Misalignments in the retinal nerve fi ber layer evaluation using cirrus high-defi nition optical coherence tomography. Journal of glaucoma. 2011;20(9):559-65.

4. Toteberg-Harms M, Sturm V, Knecht PB, Funk J, Menke MN. Repeatability of nerve fi ber layer thickness measurements in patients with glaucoma and without glaucoma using spectral-domain and time-domain OCT. Graefe's archive for clinical and experimental ophthalmology = Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie. 2012;250(2):279-87.

5. Wu H, de Boer JF, Chen TC. Diagnostic capability of spectral-domain optical coherence tomography for glaucoma. American journal of ophthalmology. 2012;153(5):815-26 e2.

6. Ye C, Lam DS, Leung CK. Retinal nerve fi ber layer imaging with spectral-domain optical coherence tomography: eff ect of multiple B-scan averaging on RNFL measurement. Journal of glaucoma. 2012;21(3):164-8.

7. Coscas G. Optical coherence tomography in age-related macular degeneration 2ed. New York: Springer-Verlag Heidelberg; 2010.

8. Fercher AF. Optical coherence tomography - development, principles, applications. Zeitschrift fur medizinische Physik. 2010;20(4):251-76.

9. Huang D, Swanson EA, Lin CP, Schuman JS, Stinson WG, Chang W, et al. Optical coherence tomography. Science. 1991;254(5035):1178-81.

10. Leitgeb RA. Optical coherence tomography--high resolution imaging of structure and function. Conference proceedings : Annual International Conference of the IEEE Engineering in Medicine and Biology Society IEEE Engineering in Medicine and Biology Society Conference. 2007;2007:530-2.

11. van Velthoven ME, Faber DJ, Verbraak FD, van Leeuwen TG, de Smet MD. Recent developments in optical coherence tomography for imaging the retina. Prog

Retin Eye Res. 2007;26(1):57-77.

12. Hee MR, Izatt JA, Swanson EA, Huang D, Schuman JS, Lin CP, et al. Optical coherence tomography of the human retina. Archives of ophthalmology. 1995;113(3):325-32.

13. Schuman JS, Hee MR, Arya AV, Pedut-Kloizman T, Puliafi to CA, Fujimoto JG, et al. Optical coherence tomography: a new tool for glaucoma diagnosis. Current opinion in ophthalmology. 1995;6(2):89-95.


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Retinoblastoma (RB) is the most common in-traocular neoplasm found in childhood, and with modern treatment modalities in most cases is curable. Retinoblastoma is a malignant tumor of the developing retina that occurs in children, usually before age 5 years, and may be unilateral or bilateral. About 60% of pa-tients have unilateral RB, with a mean age at diagnosis of 24 months, and about 40% have bilateral RB, with a mean age at diagnosis of 15 months. Mutations in the RB gene (chromo-somal location 13q14) predispose individuals to the disease, as well as to an increased risk of developing pineal tumors, extracranial sar-comas, and melanoma. When a patient with RB develops a pineal tumor, the term trilateral RB (TRB) is used.[1, 2, 3] RB may occur sporadical-ly (60%), or it may be inherited (40%). Histori-cally, the RB trait seemed to be transmitted in an autosomal dominant pattern. Occasionally, however, the trait skips a generation in fami-lies, indicating genetic carriers.

Fig. Retinoblastoma, glaucomatous stageRadiographic features

Computed Tomography

On CT scans, RB is seen as a mass that is pre-dominantly located in the posterior ocular pole. The mass may have distinct contours and an inhomogeneous structure, and it may contain calcifi cations in about 70% of case. CT scanning has high sensitivity in the detection of intraocular tumors, and it has a specifi city of 91% for RB. This modality has allowed the staging of intraocular tumors, the detection of extrabulbar growth, and the determination of further treatment approaches. CT scanning

can be used to follow up tumors to determine the eff ect of treatment and to establish a time-ly diagnosis of malignant tumor relapses.

Fig. Patient with retinoblastoma, glaucoma-tous stage. Intracranial extension on CT scan

Magnetic Resonance Imaging

Magnetic resonance imaging (MRI) is not as specifi c for diagnosing RB as CT scanning be-cause of MRI’s insensitivity for detecting calci-um. When calcium is detected, it may be seen as an area of low signal intensity on all pulse sequences.[4] RB is usually visualized as a mass that is slightly hyperintense relative to the vit-reous on T1-weighted images and that is hy-pointense on T2-weighted images. T1 hyperin-tensity may be due to the presence of melanin. Mild to marked enhancement is seen on gado-linium–enhanced T1-weighted images.Like CT scanning, MRI has a role in the detec-tion of extraocular tumor spread, especially ex-tension into the optic canal. It can also depict intracranial tumors associated with TRB.UltrasonographyThree-dimensional (3D) ultrasonography can be used to perform retinal and tumor mapping, which is useful in planning localized or plaque radiation. Subsequently, 3D ultrasonography can also help confi rm the proper positioning of such plaques. In addition, calcifi cation and retinal detachment can be diagnosed with this modality; however, 3D ultrasonography is not useful for depicting the extraocular spread of tumors. General anesthesia must be a part of this examination, because the eye should be still during the scan.[5, 6] Color Doppler imag-

Radiographic features of retinoblastomaShulav Paudel, Radiography Technologist

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ing reveals slightly vascularized tumor areas and can depict blood fl ow inside the tumor.Bone scanA bone scan can help show if the retinoblas-toma has spread to the skull and other bones. Most children with retinoblastoma do not need to have a bone scan. It is normally used only when there is a strong reason to think retinoblastoma may have spread beyond the eye. For this test, a small amount of low-lev-el radioactive material is injected into a vein intravenously. The material settles in areas of damaged bone throughout the entire skele-ton over the course of a couple of hours. Then child lies on a table for about 30 minutes while a Gamma camera detects the radioactivity and creates a picture of the skeleton. This may require sedation. This test shows the entire skeleton at once. Areas of active bone chang-es appear as “hot spots” on the skeleton – that is, they attract the radioactivity. These areas may suggest the presence of cancer, but other bone diseases can also cause the same pat-tern. To help tell these conditions apart, other imaging tests such as plain x-rays or MRI scans, or even a bone biopsy might be needed.

Angiography

Retinal fl uorescein angiography helps to con-fi rm the diagnosis of RB. However, it is not usu-ally performed for this disease because of the availability of noninvasive, cross-sectional im-aging methods.

References

1. Shields CL. Forget-me-nots in the care of children with retinoblastoma. Semin Oph-thalmol. Sep-Oct 2008;23(5):324-34. [View Ab-stract]2. Mastrangelo D, De Francesco S, Di Leonardo A, Lentini L, Hadjistilianou T. The retinoblastoma paradigm revisited. Med Sci Monit. Dec 2008;14(12):RA231-40. [View Ab-stract]3. Schefl er AC, Abramson DH. Retinoblas-toma: what is new in 2007-2008. Curr Opin Ophthalmol. Nov 2008;19(6):526-34. [View Abstract]

4. McCaff ery S, Simon EM, Fischbein NJ, et al. Three-dimensional high-resolution magnetic resonance imaging of ocular and orbital malignancies. Arch Ophthalmol. Jun 2002;120(6):747-54.5. Finger PT, Romero JM, Rosen RB, et al. Three-dimensional ultrasonography of choroidal melanoma: localization of radio-active eye plaques. Arch Ophthalmol. Mar 1998;116(3):305-12. [View Abstract]6. Romero JM, Finger PT, Iezzi R, et al. Three-dimensional ultrasonography of cho-roidal melanoma: extrascleral extension. Am J Ophthalmol. Dec 1998;126(6):842-4.

The Sight Vol. 8

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