Visual status of deaf school students in Kathmandu, Nepal
Aim: To evaluate the visual status of deaf students in Kathmandu, Nepal.
Methods: This was a descriptive cross-sectional study. All students in the school for the deaf in Kathmandu were examined over a six- month period, starting on 1st January 2005. A thorough ocular examination was done by an optometrist and the following information was recorded on a standard proforma: history, cause and duration of deafness (if known); family history of the same problem; associated systemic problems, and history of eye examinations. Visual acuity was measured in each eye using an illuminated Snellen chart with multiple optotypes. A cover test was performed to identify strabismus, and Ishihara plates were used to assess colour vision. A torch was used to examine the external eye, and a direct ophthalmoscope was used for posterior segment examination. Retinoscopy was performed where indicated. Students were referred to the eye hospital for further evaluation and management if necessary.
Results: Out of the total 253 deaf students, 56 per cent were male, and their ages ranged from from 6 to 25 years (mean 13.75 years). Over two thirds (68 per cent) had been deaf since birth but only 40 per cent knew why they were deaf. At least one other family member was also deaf in 36 students (14 per cent). Thirty students had a visual acuity of <6/9 in the better eye, but no child was bilaterally blind. Out of the total of 253, 57 students (23 per cent) had at least one ocular problem, including strabismus (7 students, exotropia>esotropia), refractive error (32 students: 22 per cent were myopic, 41 per cent were hyperopic and 38 per cent were astigmatic), corneal ulcer or scar, glaucoma suspect, and amblyopia. Six were found to have abnormal colour vision. Nine students gave a history of night blindness, but there was no evidence of retinitis pigmentosa, and all those with reduced vision were referred for assessment. No student had the typical retinal changes of congenital rubella. Only 26 students (10 per cent) had had an eye examination at any time in the past.
Conclusions: Although ocular problems were common amongst these deaf students, only a few had previously had an ocular examination. Vision is very important in deaf students, as a means of communicating and learning about the world, so they should be included in vision screening programmes. Many attend special schools and can be readily assessed by an eye care team.