Initial results of endothelial cell counts after Artisan Lens for Phakic Eyes: An evaluation of the united states food and drug administration ophtec study

Abstract

Purpose To evaluate the endothelial cell count change in eyes implanted with the iris-claw phakic Artisan lens for treatment of moderate to high myopia. Design Prospective, multicenter clinical trial. Participants The first 765 eyes enrolled at 25 North American sites in the United States Food and Drug Administration Ophtec clinical trial of the myopic Artisan IOL. Outcome analyses of endothelial cell count measurements were based on those obtained before surgery and at 6, 12, and 24 months after surgery performed between October 1998 and December 2001. Setting Multiple private and university practices. Methods Percentage change in endothelial cell count from baseline to 6, 12, and 24 months were analyzed using specular microscopy. Upper limit of detecting endothelial cell density change was estimated using 3 repeated counts at preoperative and postoperative time frames. Main outcome measures Percentage change in endothelial cell loss. Results The mean preoperative endothelial cell count was 2631±442 cells/mm 2. Percentage change from baseline at 6, 12, and 24 months was −0.09%±16.39%, −0.87%±16.35%, and −0.78%±17.41%. No statistically significative postoperative endothelial cell loss was found. The endothelial cell loss rate was higher among patients who wore spectacles before surgery and was correlated negatively with preoperative endothelial cell density ( P<0.001). No relationships were noted between endothelial cell loss and either patient age or implant power. A 4.1% repeatability of measurements was found based on the average of 3 repeated counts, whereas single cell count estimates were associated with a 23% accuracy in detecting endothelial cell density change. In a worst-case scenario, adjusting for measurement accuracy, 9% of all eyes were at higher risk of a 10% loss of cell density at 12 months after surgery, although eyes at higher risk were found to have high preoperative endothelial cell counts ( P<0.0001). Conclusions The Artisan iris-claw phakic intraocular lens did not result in significant loss of endothelial cell density up to 2 years after implantation of the myopic Artisan phakic lens.