CAUSES OF VISION IMPAIRMENT 

The following estimates are from Prevent Blindness America (National Society to 

Prevent Blindness, 1980) and reflect 1978 estimates.  While these estimates are not 

recent, they are the only comprehensive statistics which could be located which 

indicate the percentage of all cases of blindness accounted for by each disease (for 

all ages and ethnic groups). 

Existing Cases of Legal Blindness 

(Based on the number of legally blind persons in the population at a given time). 

The leading causes of existing cases of legal blindness and the percentage of 

cases of legal blindness caused by each are as follows: 

glaucoma (12.5) 

macular degeneration (11.7) 

cataract (8.3%) 

optic nerve atrophy (7.0) 

diabetic retinopathy (6.6) 

retinitis pigmentosa (RP) (4.7) 

myopia (4.0) 

all other/unknown (45.2) 

New Cases of Legal Blindness  

(New cases of legal blindness which occur during the year) 

The leading causes of new cases of legal blindness and the percentage of cases 

of legal blindness caused by each are as follows: 

macular degeneration (16.8%) 

glaucoma (11.5%) 

diabetic retinopathy (10.1%) 

cataract (9.8%)    

optic nerve atrophy (4.3%) 

all other/unknown (47.5%)  

18