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Causes of blindness and visual impairment among students in integrated schools for the blind in Nepal
Jyoti Baba Shrestha1, Subodh Gnyawali, Madan Prasad Upadhyay
1BP Koirala Lions Center for Ophthalmic Studies, Institute of Medicine, Tribhuvan University, Maharajgunj, Kathmandu, Nepal. jyotishrestha2020@yahoo.com
Purpose:
To identify the causes of blindness and visual impairment among students in integrated schools for the blind in Nepal.
Methods:
A total of 778 students from all 67 integrated schools for the blind in Nepal were examined using the World Health Organization/Prevention of Blindness Eye Examination Record for Children with Blindness and Low Vision during the study period of 3 years.
Results:
Among 831 students enrolled in the schools, 778 (93.6%) participated in the study. Mean age of students examined was 13.7 years, and the male to female ratio was 1.4:1. Among the students examined, 85.9% were blind, 10% had severe visual impairment and 4.1% were visually impaired. The cornea (22.8%) was the most common anatomical site of visual impairment, its most frequent cause being vitamin A deficiency, followed by the retina (18.4%) and lens (17.6%). Hereditary and childhood factors were responsible for visual loss in 27.9% and 22.0% of students, respectively. Etiology could not be determined in 46% of cases. Overall, 40.9% of students had avoidable causes of visual loss. Vision could be improved to a level better than 6/60 in 3.6% of students refracted.
Conclusion:
More than one third of students were visually impaired for potentially avoidable reasons, indicating lack of eye health awareness and eye care services in the community. The cause of visual impairment remained unknown in a large number of students, which indicates the need for introduction of modern diagnostic tools.
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