A comparison of anterior chamber and posterior chamber intraocular lenses after vitreous presentation during cataract surgery: the Department of Veterans Affairs Cooperative Cataract Study

Abstract

PurposeTo compare the efficacy and safety of anterior chamber (AC) intraocular lenses (IOLs) and posterior chamber (PC) IOLs implanted after vitreous presentation during extracapsular cataract extraction (ECCE). DesignThe study was a prospective, long-term, randomized clinical trial conducted at 19 Department of Veterans Affairs medical centers across the United States. MethodsThere were 438 eyes (438 patients) that met preliminary eligibility criteria, suffered vitreous presentation during ECCE (phacoemulsification or classical extracapsular technique), and had sufficient capsular support for a PC IOL without sutures after anterior vitrectomy randomized to either a PC IOL (230 patients) or an AC IOL (208 patients). Patients were examined at 3, 6, and 12 months post-surgery and yearly thereafter. Minimum follow-up was 1 year. The primary outcome measure of best-corrected visual acuity at 1 year was obtained by a masked certified examiner. ResultsMore PC IOL patients (91%) achieved visual acuity of 20/40 or better at 1 year than AC IOL patients (79%), a highly significant difference (P = .003). There was no significant difference between the two groups for patient’s rating of vision or adverse events. Over 84% of the PC IOL patients and over 77% of the AC IOL patients rated their vision as good or better at 1 year as opposed to only 7% giving such ratings before surgery. For at least one rating period during the first year, 13.2% of the combined study patients had cystoid macular edema, 8.5% had posterior capsule opacification, 5.7% had glaucoma, and 3.7% had retinal detachment. ConclusionIn the presence of sufficient capsular support, a PC IOL should be implanted after vitreous presentation during ECCE.