Long-term visual outcomes in the Cataract-Free Zone Project in Brazil.

Abstract

To determine the long-term visual outcomes and causes of poor vision in the cataract population in Brazil treated in the Cataract-Free Zone Project. Project A subjects (62 patients) were recruited in Taquaritinga, SP, 26 months after surgery. Project B subjects (34 patients) were recruited in São João da Boa Vista, SP, 43 months after surgery. All patients underwent visual screening and eye examination (examination 1). They were classified according to visual acuity in the operated eye and the causes of poor vision were diagnosed and referred for treatment. The results of these interventions were collected (examination 2) and analysed by Chi-square test. At examination 1 in project A, 47 of 62 patients (75.6%) had visual acuity < or = 20/100. The main causes of poor vision were refractive error (31.9%) and posterior capsule opacification (17.0%), with or without refractive error. At examination 1 in project B, 22 of 34 patients (64.7%) had visual acuity < or = 20/100. The main causes of poor vision were again posterior capsule opacification (50.0%) and refractive error (9.0%). After posterior capsulotomy with Nd:YAG laser and prescription of new corrective eyeglasses, visual acuity = 20/80 was obtained in 64.5% of patients in project A (OR = 0.18, CI = 0.07-0.41) and 70.5% of patients in project B (OR = 0.19, CI = 0.06-0.60) at examination 2. The causes of blindness in the remaining patients were identified. This type of project is effective in reducing blindness caused by cataracts in developing countries. However, long-term scheduled follow-up of operated patients is an effective means of avoiding consecutive blindness resulting from secondary cataracts and refractive changes.