Causes of binocular legal blindness in an australian metropolitan community.

Australian legal blindness is defined as bilateral corrected visual acuity less than 6/60; if visual acuity is better than this, collateral visual impairments may be included. Persons thus affected qualify for the Invalid Pension (Blindness). From October 1975 to June 1982, I studied clinical data of 311 persons assessed as legally blind, and recorded diagnoses. I personally examined 259 of these persons and a medical colleague examined 52. Examinees were resident in Brisbane (or environs), Australia. Eleven persons had asymmetrical conditions (analysed separately), and 300 had symmetrical conditions. Causes of the latter were genetically transmissible (20.3%), adult maculopathy (18%), congenital (12.7%), vascular (non-diabetic) (8.7%), adult glaucoma (8.3%), diabetes (7.3%), trauma (6%), and others (18.7%). Of 61 symmetrical genetic cases causes were retinitis pigmentosa (34.4%), congenital cataracts (16.4%), retinal dystrophy and maculopathy (13.1%), Leber's optic atrophy (9.8%), and others (26.3%). These results suggest that more attention should be directed to genetic counselling.