Table 3. Principal cause of bilateral blindness (VA<3/60), bilateral severe visual impairment (VA<6/60–3/60) and bilateral visual impairment (VA<6/80–6/60) among persons with available correction.
| Blindness | Severe Visual impairment | Visual impairment | ||||
| n | % | n | % | n | % | |
| Refractive error | 0 | (0%) | 6 | (22%) | 67 | (50%) |
| Cataract, untreated | 10 | (27%) | 10 | (37%) | 36 | (27%) |
| Aphakia uncorrected | 1 | (3%) | 0 | (0%) | 0 | (0%) |
| Cataract surgical complications | 0 | (0%) | 0 | (0%) | 2 | (2%) |
| Phthisis | 1 | (3%) | 0 | (0%) | 0 | (0%) |
| Other corneal scar | 1 | (3%) | 1 | (3%) | 1 | (1%) |
| Avoidable vision loss a | 13 | (35%) | 17 | (63%) | 106 | (80%) |
| Diabetic retinopathy | 3 | (8%) | 3 | (11%) | 3 | (2%) |
| Glaucoma | 4 | (11%) | 2 | (7%) | 8 | (6%) |
| Age related macular degeneration | 4 | (11%) | 2 | (7%) | 2 | (2%) |
| Other posterior segment | 13 | (35%) | 7 | (13%) | 24 | (18%) |
| Total posterior segment | 24 | (65%) | 11 | (37%) | 27 | (20%) |
VA, Visual Acuity.
a
Avoidable causes: Cataract (including un-operated cataract and postoperative complications), refractive error, trachoma, and other causes of corneal scars.