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The Sofia Eye Survey was a population-based blindness and visual impairment survey of 6,275 randomly selected men and women from the Sofia district and Sofia city in western Bulgaria. A complete house-to-house census on all adults over age 40 years was performed, and visual acuity performed on 98%. We referred 171 subjects for a complete dilated ophthalmologic examination because the pinhole vision in the better eye was 6/18 or worse. Trained ophthalmologists refracted all referred subjects and then examined them with a slit lamp and ophthalmoscopy to determine the cause of visual loss. The rate of blindness (defined as vision in the better eye worse than 3/60) in this population was 0.49% and the rate of visual impairment (6/18 to 3/60 in the better eye) was 0.83%. The leading cause of both blindness and visual impairment was cataract. These data from the first community-based survey of blindness in Eastern Europe suggest that the rates of blindness and visual impairment are similar to those reported from other developed countries.
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Vassileva et al. (1996) studied this question.
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