Prevalence and causes of blindness and low vision in Dambatta local government area, Kano State, Nigeria.

In 1995 a population based cross sectional blindness prevalence survey was conducted in Dambatta local government area (LGA). 3596 people were examined. The prevalence of blindness was 1.14% with 95% confidence limit of (0.8-1.48%). The causes of blindness are cataract 54%, Trachoma 17%, Glaucoma 15%, Corneal opacity 7%, other blinding conditions 7%. The prevalence of low vision was 2.05% with 95% confidence limit (1.60-2.50%). One percent of the population were severely visually impaired (WHO category 2). The causes of low vision are cataract 55%, corneal opacity 14%, uncorrected aphakia 11%, Glaucoma 7%, Refractive error 5%, other conditions 8 percent. Cataract was the leading cause of uniocular blindness with 53%, others were phthisis bulbi 17%, Trauma 14%, corneal opacity 10%, and others 7 percent. Cataract was the single most important cause of blindness, low vision and uniocular blindness accounting for 54%, 55%, and 53%, respectively. Uncorrected aphakia accounted for 11% of the low vision group, 80% of these had couching. This study showed that 93% of the blindness was avoidable in the sense that it could have been primarily prevented or, is treatable. 92% of the causes of low vision are avoidable.