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The main causes for 63 patients diagnosed with blindness. “Blindness” means central visual acuity of 20/200 or less in the better eye with the use of a correcting lens. An eye that is accompanied by a limitation in the fields of vision so that the widest diameter of the visual field subtends an angle no greater than 20° which is considered as having a central visual acuity of 20/200 or less. Blindness in some patients is caused by multiple factors, so the percentage sum is not 100%.
