Operated and unoperated cataract in Australia

Purpose: To quantify the prevalence of cataract, the outcomes of cataract s urgery and the factors related to unoperated cataract in Australia. Methods: Participants were recruited from the Visual Impairment Project: a cluster, stratified sample of more than 5000 Victorians aged 40 years and o ver. At examination sites interviews, clinical examinations and lens photog raphy were performed. Cataract was defined in participants who had: had pre vious cataract surgery, cortical cataract greater than 4/16, nuclear greate r than Wilmer standard 2, or posterior subcapsular greater than 1 mm(2). Results: The participant group comprised 3271 Melbourne residents, 403 Melb ourne nursing home residents and 1473 rural residents. The weighted rate of any cataract in Victoria was 21.5%. The overall weighted rate of prior cat aract surgery was 3.79%. Two hundred and forty-nine eyes had had prior cata ract surgery. Of these 249 procedures, 49 (20%) were aphakic, 6 (2.4%) had anterior chamber intraocular lenses and 194 (78%) had posterior chamber int raocular lenses. Two hundred and eleven of these operated eyes (85%) had be st-corrected visual acuity of 6/12 or better, the legal requirement for a d river's license. Twenty-seven (11%) had visual acuity of less than 6/18 (mo derate vision impairment). Complications of cataract surgery caused reduced vision in four of the 27 eyes (15%), or 1.9% of operated eyes. Three of th ese four eyes had undergone intracapsular cataract extraction and the fourt h eye had an opaque posterior capsule. No one had bilateral vision impairme nt as a result of cataract surgery. Surprisingly, no particular demographic factors (such as age, gender, rural residence, occupation, employment stat us, health insurance status, ethnicity) were related to the presence of uno perated cataract. Conclusions: Although the overall prevalence of cataract is quite high, no particular subgroup is systematically under-serviced in terms of cataract s urgery. Overall, the results of cataract surgery are very good, with the ma jority of eyes achieving driving vision following cataract extraction.