CONTACT LENS FOR PRESBYOPES

OPTOM FASLU MUHAMMED

A large % of population needs correction for Presbyopia

100 million presbyopes in india & 10 million adding every year

PRESBYOPIA

It’s a part of normal ageing process,where the eye loses its ability to easily focus on near objects

So, need near correction.

Single Vision Reading Glasses,Bifocals,Trifocals OR Multifocal With Contact Lenses On The Eye There Are 2 Options to Correct Near Vision With Spectacle Over Contact lens

CORRECTING OPTIONS

OPTION 1: Fit CL For Distance; Don’t Overcorrect

* Determine Near Addition Over CL On Trial Frame

*Prescribe Reading Glass Over CL

OPTION 2 : Ideal For Pt’s Who Do Near/Intermediate Work All Day

*Give near add on CL*Give Minus Power For Distance In The Form

Of Spectacles For Driving And Other Distance Task

Highly motivated Those who have adequate tear film & no lid

disease/ abnormality Whose jobs don’t require fine va Affordability

PATIENT SELECTION

MONOVISION CORRECTION

ALTERNATING/TRANSLATING VISION LENSES

SIMULTANEOUS VISION LENSES

CL PRESBYOPIA CORRECTION

Eye Dominance Test

Equipment required: your arms and hands, and an object about 10 feet (3 meters) away

Procedure: Extend both arms in front of your body and place the hands together so as to make a small triangle between your thumbs and the first knuckle (see image). With both of your eyes open, look through the triangle and focus on a specific small object. Close your left eye. If the object remains in view, you are right eye dominant. If your hands appear to move off the object and move to the left, then you are left eye dominant.

ONE EYE IS CORRECTED FOR DISTANCE VISION OTHER EYE FOR NEAR VISION

IT’S THE EASIEST & AN EFFECTIVE MEANS OF CORRECTING PRESBYOPIA

SUCCESS RATE IS AS HIGH AS 70%

MONOVISION

The visual system can suppress the central focus image thus enable the object of interest to be seen clearly .

PRINCIPLE

Determine the distance & near corescription Determine the dominant and non-dominant

eye Fit The Dominant With The Distance POWER

Prescrptn And Non Dominant Eye For Near Power Prescrptn

FITTING PROCEDURE

EG:-4.00 DSPH (OU) ADD +1.50 DSPH (OU) Dominant Eye With -4.00 DSPH(DISTANCE) &

Non Dominant With -2.50 DSPH (NEAR )

Use disposable lens and give an office trial. Record BVA for distance and near

Don’t attempt uniocular VA now The eye with near power’ll read less for

distance and eye with distance power’ll read less for near

Explain fitting technique now Some pt’s may need sum adaptatn time &

may be dissatisfied with reduction of stereopsis

Follow up,and fit the final lens

Adaptation time-atleast 2 wks Advise-continue normal activities if possible No night driving Don’t compare eyes Set pt’s expectations Educate visual improvement overtime

TIPS-MONOCULAR VN FITTING

Translating Vision typesLike executive type bifocal spectacle lensPt when look down gaze lower lid lifts the

near segments up, towards the pupil /the visual axis thus the pt see clear for near

Popular in RGP Near and far can’t be seen clearly same

time

BIFOCAL/MULTIFOCAL CL

Sharp near/far vision When it works well,it’s very successful Works Better In Rgp & Less

Successful/Common In Scl

ADVANTAGES

Takes longer in adaptation Comfort is less due to thick design Dependence on eye -lens relationship

DISADVANTAGES

Distance & near images focused on retina simultaneously

Brain’ll be select/concentrate on one /other will be ignored

Like looking via net across the window @ distance object

SIMULTANEOUS VN

Sharp near and far vision

DISADVNTGESCompromised intermediate vision

Ghosting(doubling) is sometimes a problem

ADVNTGES

1.CONCENTRIC DESIGNConcentric segment show sharp demarcation

b/w distance and near powers

2 TYPES

Center nearCenter distance

3 TYPES

2.Diffractive bifocal Made up of concentric rings, Something like

a fresnel prism Higher the addition more no; of rings

3.Aspheric DesignsProg.Addition type of lens formed with

alteration in ant. & Post. Curvature of lens Power is uniformly increase/decreases in

periphery due to asphericity

One eye is fitted with distance correction and other eye is bifocal lens

Improves binocularity & stereo acuity which may be reduced in mono Vn

Tried in pt’s who are sensitive to distance vn

MODIFIED MONO VISION

High myopes Pts with busy schedules Dry eyes Flat corneas Laxity of lower lid High astigmatism External ocular disease / abnormality

UNSUCCESSFUL CL FITTING -PRESBYOPES

THANK YOUUUU