COMPARISON OF A DIFFRACTIVE BIFOCAL AND A MONOFOCAL INTRAOCULAR-LENS

Purpose: To compare a Pharmacia diffractive bifocal intraocular lens ( IOL) with a monofocal lens of the same design without the diffractive grating. Setting: Multicenter study. Methods: This randomized, prospec tive study comprised 70 patients with a monofocal IOL and 79 with a di ffractive bifocal IOL. Follow-up was 5 to 6 months. Near and distance visual acuities, contrast sensitivity, patient satisfaction, and spect acle use were evaluated. Results: All patients achieved a best correct ed visual acuity of 0.5 or better; 80% in the monofocal and 71% in the bifocal group had a best corrected visual acuity of 1.0 or better. Wi thout correction, 93% of the bifocal and 9% of the monofocal group cou ld read J3 or better. With distance correction, 99% and 4%, respective ly, could read J3 or better. Contrast sensitivity was slightly lower i n the bifocal group at distance and near for all spatial frequencies, In the bifocal group, 46% never used spectacles for near tasks. Overal l satisfaction was rated good by 86% of the monofocal and 85% of the b ifocal group. Conclusions: The diffractive bifocal IOL performed well at distance and near. Patients who no longer require spectacles will b enefit significantly from a bifocal IOL but many with a bifocal IOL in one eye wilt require spectacles for the fellow eye.