Symmetric bilateral implantation of a distance-dominant diffractive bifocal intraocular lens

Abstract
To assess visual results after symmetrical bilateral implantation of a distance-dominant bifocal diffractive intraocular lens (IOL). Fernández-Vega Ophthalmological Institute, Oviedo, Spain. Fifty patients had bilateral implantation of a distance-dominant diffractive bifocal 447D IOL (Acri.Tec GmbH) in a prospective study. Monocular and binocular best corrected distance visual acuities and best distance-corrected near visual acuity, binocular best distance-corrected intermediate visual acuity, and distance contrast sensitivity under photopic (85 cd/m(2)) and mesopic (5 cd/m(2)) conditions were determined. At the 6-month postoperative visit, the mean binocular best corrected distance acuity and best corrected distance near acuity were 0.02 +/- 0.04 logMAR and 0.04 +/- 0.03 logMAR, respectively. Binocular best corrected distance intermediate visual acuity worsened significantly as a function of the distance of the test: from 0.04 +/- 0.03 logMAR at 33 cm to 0.21 +/- 0.08 logMAR at 70 cm (P<.01). Contrast sensitivity was within normal limits under photopic and mesopic conditions. Binocular contrast sensitivity was statistically significantly better than monocular contrast sensitivity at all spatial frequencies under both illumination levels (P<.01). Bilateral implantation of the distance-dominant bifocal 447D IOL provided good simultaneous distance, near, and intermediate vision with improved contrast sensitivity under photopic and mesopic conditions.