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The prevalence and causes of visual impairment in central Sri Lanka the Kandy Eye study
Kapila Edussuriya1, Saman Sennanayake, Tissa Senaratne
1Department of Ophthalmology, General Hospital, Kandy, Sri Lanka.
Objective:
To determine the prevalence and causes of uncorrectable visual impairment in the Kandy District of central Sri Lanka.
Design:
Population-based, cross-sectional study.
Participants:
Inhabitants >or=40 years of age from villages in the Kandy District were selected by randomized cluster sampling; 1721 eligible participants were identified and 1375 participated in the study.
Methods:
The ophthalmic examination included best-corrected logarithm of the minimum angle of resolution visual acuity (VA), slit-lamp examination of the anterior segment, and dilated stereoscopic fundus examination. The principal cause of visual impairment after best correction was recorded.
Main Outcome Measures:
Visual impairment (better eye <6/18) and blindness (better eye <3/60) after best correction.
Results:
Comprehensive examinations, including VA, were performed on 1375 subjects (79.9% participation rate). The prevalence of blindness was 1.1% (95% confidence interval [CI], 0.002-0.020; 15 participants). The prevalence of visual impairment was 5.9% (95% CI, 0.043-0.075; 81 subjects). Cataract and age-related macular degeneration were the main causes of visual impairment.
Conclusions:
Visual impairment remains a major public health problem in central Sri Lanka. Specific programs directed at reducing the cataract burden need to be implemented.
Financial Disclosure(S):
The authors have no proprietary or commercial interest in any materials discussed in this article.
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