RANDOMIZED CONTROLLED TRIAL OF ANTERIOR-CHAMBER INTRAOCULAR LENSES

Background There are an estimated 16 million people blind in both eyes with cataracts. Most live in rural areas of developing countries wher e surgical resources are scarce. There is no consensus on the most app ropriate type of intraocular lens in situations where high-volume low- cost surgery is required, This study was undertaken to evaluate the sa fety of multiflex open-loop anterior-chamber lenses (ACIOLs). Methods 2000 people attending Lahan Eye Hospital, southern Nepal, with bilater al cataracts reducing vision to 6/36 or less were randomly allocated t o receive standard surgery-intracapsular extraction (ICCE) with aphaki c correction-or ICCE with an ACIOL in their first operated eye. The pr imary outcome was a visual acuity of less than 6/60 in the operated ey e at 1 year follow-up. Visual acuity was measured for 91% of the cohor t at 1 year, The sample size was estimated to detect a doubling in poo r visual outcome from an estimated rate of 4% in the standard surgery (control) group. Findings The median (range) time taken to do the surg ery was 6.0 (3.0-17.2) min for the ACIOL group and 4.1 (2.4-10.3) min for the control group. 1 year after surgery, 5.0% of the ACIOL group a nd 5.4% of controls had functional Vision less than 6/60 (OR 0.93 [0.6 0-1.43], p=0.71). The causes of poor vision in the ACIOL and control g roups were: correctable refractive error (22 and 29), uveitis/secondar y glaucoma (13 and two), endophthalmitis (four and seven), pre-existin g eye disease (four and five), retinal detachment (none and four), cys toid macular oedema (two and none), corneal ulcer (one and one), and c orneal decompensation (none and one). Interpretation This study provid es evidence that, in rural areas of developing countries, multiflex op en-loop ACIOLs can be implanted safely by experienced ophthalmologists after routine ICCE, avoiding the disadvantages of aphakic spectacle c orrection. Further follow-up is planned.