Clinical evaluation of the Crystalens AT-45 accommodating intraocular lens: results of the U.S. Food and Drug Administration clinical trial.
PURPOSE: To evaluate the 12-month U.S. phase II clinical trial results of the Crystalens AT-45 (eyeonics, Inc.) intraocular lens (IOL) used to provide uncorrected distance, intermediate, and near visual acuities in patients having cataract extraction and to compare in a substudy the contrast sensitivity and near visual acuity in patients with the Crystalens AT-45 IOL and those receiving a standard IOL. SETTING: Fourteen clinical sites throughout the U.S. for efficacy and 3 non-U.S. sites for safety and efficacy. METHODS: Patients 50 years or older had small-incision cataract extraction with implantation of the Crystalens AT-45 IOL. Unilateral implantation was followed by fellow-eye implantation. Postoperatively, uncorrected distance, near, and intermediate visual acuities were determined. Near and intermediate visual acuities were tested through a distance correction to eliminate potential pseudoaccommodative effects of residual myopia and corneal cylinder. A substudy tested contrast sensitivity under mesopic conditions with and without glare, as well as visual acuity in a subset of Crystalens AT-45 patients and a control group receiving a standard IOL. RESULTS: A total of 263 patients participated in the U.S. clinical trial and had 1 year of follow-up. Near visual acuities through the distance correction of 20/40 (J3) or better, monocularly and bilaterally, respectively, were seen in 90.1% and 100%; intermediate near visual acuities were seen in 99.6% and 100%. More than half the bilaterally implanted Crystalens AT-45 patients achieved uncorrected near acuity of 20/25 (J1) or better through the distance correction, and 84% achieved 20/32 (J2) or better. In the substudy, monocular near vision through the distance correction of 20/25 (J1) or better was seen in 50.4% with the Crystalens AT-45 IOL and in 4.7% with the standard IOLs. Mesopic contrast sensitivity results with and without glare for the Crystalens AT-45 were similar to those with standard monofocal IOLs. Nearly all patients (74 patients; 97.3%) who bilaterally were within 0.50 diopter of plano postoperatively achieved 20/32 (J2) or better uncorrected near, intermediate, and distance visual acuities. CONCLUSIONS: The Crystalens AT-45 accommodating IOL provided good uncorrected near, intermediate, and distance vision in pseudophakic patients. Contrast sensitivity with the Crystalens AT-45 was not diminished relative to standard monofocal IOLs, and near and intermediate visual performance was significantly better than with standard IOLs.