College of Ophthalmologists of Sri Lanka Naonal ... - cosl.lk
Transcript of College of Ophthalmologists of Sri Lanka Naonal ... - cosl.lk
College of Ophthalmologists of Sri Lanka
&
Na�onal Transport Medical Ins�tute
Vision Standards for
Driving License in Sri Lanka
Revised Edi�on with Amendments Effec�ve from 1�� February 2021
My Dear Colleagues and friends,
It is my pleasure to write this message to this booklet to introduce the vision standards for drivers in Sri Lanka, set out by the College of Ophthalmologists of Sri Lanka.
As a leading professional body in the country, the advocacy role we play is very important to influence decisions within the poli�cal, economic and social systems and ins�tu�ons. We closely collaborated with the Na�onal Transport Medical Ins�tute and formulated the vision standards for driving license.
Although many factors contribute to safe driving, crash rates and driving-related injuries have a strong associa�on with deteriora�on of vision. Consequently, licensing authori�es have ins�tuted minimum vision requirements for maintaining driving privileges.
The number of pa�ents with visual impairments due to progressive eye diseases, such as glaucoma, diabe�c re�nopathy and macular degenera�on is expected to rise in coming years as the popula�on ages worldwide. So it is essen�al for adequate standards of vision to be set for the driver.
I would like to take this opportunity to thank Dr. Muditha Kulathunga, senior consultant ophthalmologist for her valuable contribu�on made to set up these guidelines. Also I appreciate the support rendered by the medical staff at the Na�onal Transport Medical Unit in formula�ng these guidelines. These guidelines are set down as either statutory requirements or guidance from the College of Ophthalmologists of Sri Lanka.
I hope this booklet on vision standards for driving license will benefit our membership.
Thank you,
Dr. Dilruwani Aryasignha (MBBS, MD, FRCS)
President, 2019 College of Ophthalmologists of Sri Lanka
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COSL President’s Message 2019
Collabora�on mee�ngs with the
Na�onal Transport Medical Ins�tute
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Summary
The following change had been made to the Vision Standards for Driving
License in Sri Lanka by the College of Ophthalmologists of Sri Lanka with
effect from 1�� February 2021.
Include a best corrected or minimum vision of 6/12 be�er eye and 6/60
worse eye to the intermediate category (only to drive non commercial
vehicles).
Monocular category is redefined as 6/9 be�er eye and 6/Nil (<6/60)
worse eye to drive modified light vehicles.
Visual acuity (with or without spectacles )
Addi�onal tests Category
Be�er eye Worse eye
6/9
6/12
6/126/126/186/246/366/60
Adequate VF
Adequate VF
All vehicles
Intermediate category non
commercial light vehicles,
three wheelers and motor
cycles
6/9 Less than 6/60
Less than 6/60
Monocular (Modified light vehicle for personal use only)
6/12 CANNOT drive in Sri Lanka
CANNOT drive in Sri LankaBe�er eye maximum vision less than 6/18
Non commercial light vehicles, three wheelers and motor cycles (renewal or new applicants)
Normal Visual Fields
Some degree of BSV
ONLY renewals of heavy vehicles or commercial driving (Not for new applicants of heavy or commercial vehicles)
Squint
-
-
-
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Vision Standards for Driving License in Sri Lanka
With the ever increasing number of vehicles using our roads, it is
inevitable that drivers need to call upon increasing use of sensory and
motor skills in order to nego�ate safely through the traffic. Approximately
95% of the sensory input to the brain required for driving comes from
vision. So it is obviously essen�al for adequate standards of vision to be
set for the driver of any vehicle and these are set down as either statutory
requirements or guidance from the professional body i.e. The College of
Ophthalmologists of Sri Lanka.
Ini�al and renewal applicants are required to take and pass a
vision test before being issued a license.
The “private /personal vehicle” standards should be applied to:
• Drivers applying for or holding a license for a car, motorcycle, three wheeler or a light rigid vehicle not used to carry public passengers for hire.
• The vehicle need not be under their name
• The department of motor traffic should indicate that it is a “non
commercial license holder” in the license so that police can check and
take ac�on against improper use of the license
The “commercial vehicle” standards should be applied to:
• Drivers of “heavy vehicles” (i.e. those holding or applying for a license of classes DE, D, C, D1, C1, CE, J and PT)
• Drivers carrying public passengers for hire (taxi/cab drivers, chauffeurs, drivers of hiring three wheelers and school vans, etc.)
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Vehicle Type Commercial passenger transport vehicles and all Heavy vehicles
Light vehicles for personal use (not for commercial passenger transport)
Three Wheeler for
personal use (not
for commercial
passenger
transport) and
Motorcycles
Visual acuity
Snellens test type
and the standard
near vision tes�ng
should be used.
6/12 in each eye
with or without
glasses.
Should wear
correc�ve lenses
(Spectacles/
contacts) when
driving.
The appropriate
correc�on needs to
be tolerated by the
driver.
6/9, 6/12 or vice
versa with or
without glasses.
Should wear
correc�ve lenses
(Spectacles/
contacts) when
driving.
The appropriate
correc�on needs
to be tolerated by
the driver.
6/12 in each eye
with or without
glasses.
Should wear
correc�ve lenses
(Spectacles/
contacts) when
driving.
The appropriate
correc�on needs
to be tolerated by
the driver.
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Intermediate Vision
Absolute contraindica�on
Corrected vision Be�er eye 6/12 Worse eye: 6/18 to 6/60
Refer to eye surgeon – check visual fields – if adequate can allow
Indicate: “For personal use without modifica�ons”
Corrected vision Be�er eye 6/12 Worse eye: 6/18 to 6/60
Refer to eye surgeon – check visual fields – if adequate can allow.
For three wheelers indicate: “For personal use ”
Field of vision
Test should be carried out binocular
Esterman visual fields (white target size Goldman iii4 e)
140� in the
horizontal
meridian No defect within
20� from fixa�on
horizontally or
ver�cally.
140� in the
horizontal
meridian No defect within
20� from fixa�on
horizontally or
ver�cally.
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Monocular vision (worse eye: less than 6/60)
Contraindicated as modifica�ons cannot be done.
Monocular vision Absolute contraindica�on
Monocular vision (worse eye: less than 6/60) Under special circumstances on an individual basis could be considered provided that following criteria are met.
1. Visual acuity is 6/9 or be�er with or without correc�on.
2. Uncorrected minimum vision should be 6/36.
3. Visual fields – 120� in the horizontal meridian No extension of peripheral defect within 20� from fixa�on horizontally or ver�cally. Within central 20� single missed point or cluster of 3 adjoining points is acceptable if
140� in the horizontal meridianDefect in one eye should be completely compensated by the other eye
(worse eye: less than 6/12)
there are no other field defects
Indicate: “For personal use with modifica�ons”
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Colour blindness No restric�on No restric�on No restric�on
Diplopia Absolute contraindica�on
Assess on an individual basis. Diplopia in the primary posi�on presents an extreme hazard to safe driving. Cessa�on of driving un�l the diplopia is controlled with patching or glasses with prisms. Can allow as long as criteria for vision and visual fields are met a�er a period of 6 months if there is sa�sfactory func�onal adapta�on.
Assess on an individual basis. Diplopia in the primary posi�on presents an extreme hazard to safe driving. Cessa�on of driving un�l the diplopia is controlled with patching or glasses with prisms. Can allow as long as criteria for vision and visual fields are met a�er a period of 6 months if there is sa�sfac- tory func�onal adapta�on.
Progressive
disorders
affec�ng vision /
visual field or
night vision.
Absolute
contraindica�onCan allow as long as criteria for vision and visual fields are met.
Review every 2 years for renewal of the license.
Can allow as long as criteria for vision and visual fields are met.
Consider on an individual basis renewal on individual basis – eye surgeon will decide
Nystagmus Absolute
contraindica�on
Can allow as long
as criteria for
vision and visual
fields are met.
Can allow as long
as criteria for
vision and visual
fields are met.
Monocular vision (worse eye: Less than 6/60) is Contraindicated for Three Wheelers for personal use and Motorcycles as modifica�ons cannot be done.
Absolute contraindica�on
Blepharospasm Consider on an
individual basis.
Can allow grade
one and two (not
func�onally
disabling) as long
as criteria for vision
and visual fields
are met.
Consider on an
individual basis.
Can allow grade
one and two as
long as criteria for
vision and visual
fields are met.
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Assess on an individual basis. If a squint with adequate visual acuity and visual fields can be allowed even if there is no BSV. Squint with diplopia, consider criteria for diplopia.
Assess on an individual basis. If a squint with adequate visual acuity and visual fields can be allowed even if there is no BSV.
Squint with diplopia, consider criteria for diplopia.
Squint Absolute contraindica�on for new applicants
Consider if it is a renewal of license: Refer to ophthalmologist– criteria for visual acuity and visual fields should be met. Some grade of BSV should be present.
Notes on visual fields
The minimum visual field for safe driving is a field of vision of at least 120�
on the horizontal meridian measured by the Goldmann perimeter on the
III 4e se�ngs (or equivalent perimetry). In addi�on there should be not
more than a cluster of 3 non seeing spots in the binocular field which
encroaches within the central 20� of fixa�on. By this means, homonymous
or bitemporal defects which come within 20� of fixa�on, whether
hemianopic or quadrantanopic, are not accepted as safe for driving.
Isolated scotomata represented in the binocular field near the central
fixa�on area are also inconsistent with safe driving.
The test must therefore monitor the central area of field as well as its
outer perimeter and the intervening meridians. It is obviously essen�al
that the applica�on of the standard should not be equipment specific and
the phrase “equivalent perimetry” allows the development of equivalent
programs using other perimeters including autoperimeters.
Suprathreshold screening tests which cover the central and peripheral
field in each eye are commonly available on most autoperimeters and will
sa�sfy the standard. Central threshold tests, commonly used for rou�ne
monitoring of glaucoma, are helpful in assessing the significance of a
scotoma in the central field but in isola�on are not useful.
Where the driver has obvious field defects such as a homonymous
hemianopia or quadrantanopia then no confusion arises and the licence is
refused. This applies even when the pa�ent has, for whatever reason,
been driving with this condi�on for many years. The problem arises,
however, when there are equivocal field losses that only just encroach
into the permi�ed field for driving. These may not necessarily be
repeatable especially in the elderly who can have problems mastering the
perimeter, or in pa�ents with early glaucoma or lightly photocoagulated
diabe�cs. To be fair to these pa�ents, it is important to test them on more
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than one occasion to enable an appropriate decision to be made regarding
their driving ability. The Esterman binocular field test allows some
enhancement of the binocular field as occurs naturally and also allows
fixa�on by the dominant eye. Hence it can be seen to be the least stringent
test fulfilling the required standard. It may therefore be used to the
benefit of the pa�ent. However, it must be stated that if the Esterman test
is failed, even by one spot within the 20� limit, it is likely that this
represents a significant scotoma which will lead to the loss of the driving
license. The score given by the program is weighted to the areas of field
important to driving but is of li�le help in the assessment of the standard.
Severe bitemporal hemianopia which extends to the midline on either
side can s�ll give a horizontal binocular field of 120� on an Esterman or
other binocular field by way of binasal vision. It is felt that despite this
“full” field, driving is unsafe due to the instability of the two hemifields and
the inability of the driver to “lock” the fields from the two eyes together.
Some pa�ents produce very different field test results at different �mes
and it is important to maximize reliability and reproducibility of the visual
field test in all cases. False nega�ve and posi�ve errors as well as fixa�on
losses must be minimized to produce accurate results. A field should be
rejected if there are more than 20% of false posi�ve errors. A perimetrist
should be present with the pa�ent at all �mes during the test and should
carefully explain the test to the pa�ent prior to beginning. Spectacles,
especially for a high ametrope, may produce aberra�ons and a more
accurate test may be produced without them.
Note:- NTMI will inform the public to obtain a Esterman visual field test
prior to seeing the consultant ophthalmologist regarding the driving
license.
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One needs to check the iden�ty of the person before performing the visual field test.
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Notes on monocular vision
Monocular vision is not a cause for disqualifica�on for light vehicles for
personal use (not for commercial/hiring passenger transport) provided
the visual field in the remaining eye is within the above defini�on. This
physiological blind spot may be picked up on an Esterman test in a
monocular pa�ent and if this is the case, other central visual field tests
such as the Humphrey 24-2 threshold tests should be supplied to
demonstrate the otherwise normality of the central field.
For drivers with monocular vision following modifica�ons to the vehicle
should be considered. Modified vehicle must present at the �me of
examina�on.
1. Disable symbol should be displayed
2. Only specified motor vehicle
3. 2 rear mirrors and 2 front mirrors
4. Speed has to be decided by the DMT
5. A�er making modifica�ons to the vehicle need to allow at least 6
months adapta�on �me from the �me of loss of vision on one
side or as decided by the consultant ophthalmologist.
Note on BSV
For renewals – for heavy and commercial vehicle drivers with long term
squints need to be able to perform Lang II (600 seconds of an arc) or
Titmus (800 seconds) test correctly.
Notes on Blepharospasm
Grades
Blepharospasm Severity
0 = None
1 = Minimal, increased blinking present only with external s�muli (e.g.,
bright light, wind, reading, driving, etc.)
2 = Mild, but spontaneous eyelid flu�ering (without actual spasm),
definitely no�ceable, possibly embarrassing, but not func�onally
disabling)
3 = Moderate, very no�ceable spasm of eyelids only, mildly
incapacita�ng
4 = Severe, incapacita�ng spasm of eyelids and possibly other facial
muscles
Blepharospasm Frequency
0 = None
1 = Slightly increased frequency of blinking
2 = Eyelid flu�ering las�ng less than 1 second in dura�on
3 = Eyelid spasm las�ng more than 1 second, but eyes open more than
50% of the waking �me
4 = Func�onally “blind” due to persistent eye closure (blepharospasm)
more than 50% of the waking �me
Vision standards for driving license should be checked by a board cer�fied consultant ophthalmologist /ac�ng consultant ophthalmologist awai�ng board cer�fica�on.
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Acknowledgement
Dr. Muditha Kulatunga DO, MS, FRCS
Dr. Dilruwani Aryasingha MBBS, MD, FRCS
Dr. Deepanee Wewalwala MS, FRCS
Dr. T. I. Jayasekara MBBS (Col); Dip Psychology; MSc Psych (UK)
Dr. W. G. N. Fonseka MBBS (NCMC), DFM
Dr. K. S. M. Samarasekara (CMO-NTMI) MBBS (NCMC), P.G Dip (OH & S)
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