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What is WHO definition of blindness? and explain in detail?
Answer: A. visual acuity less than 3/60 or its equivalent. (Ref. Park's Textbook of PSM 22nd/Pg.371)WHO defines blindness as visual acuity of less than 3/60(Snellen) or its equivalent. WHO added that inability to count fingers in daylight at a distance of 3 m.Categories Of Visual ImpairmentMaximum Visual Acuity Less ThanMinimum Visual Acuity Equal To Or Better ThanLow vision1. 6/186/60 2. 6/603/50Blindness3. 3/60 (finger counting at 3 metres)1/60 (finger counting at 3 metres) 4. 1/60 (finger counting at 3 metres)5. No light perceptionLight perception