Table 1 Visual impairment criteria*
From: The effect of different criteria on the number of patients blind from open-angle glaucoma
WHO | US | US SSA | |
|---|---|---|---|
Low vision | VA < 0.3 (20/70) and/or a constriction of the central visual field to < 20° | VA < 0.5 (20/40). | MD ≤ -22 dB in both eyes. |
Blindness | VA < 0.05 (20/400) and/or a constriction of the central visual field to < 10° | VA ≤ 0.1 (6/60) and/or a constriction of the central visual field to < 20° |