Prominent decrease of superior midperipheral endothelial cell density after iris-fixated phakic intraocular lens implantation

PURPOSE: To evaluate changes in endothelial cell density (ECD) in the corneal region after implantation of an iris-fixated phakic intraocular lens (PIOL). METHODS: Forty-five eyes of 25 myopic patients implanted with Artisan iris-fixated PIOLs (Ophtec BV) and 30 eyes of 15 myopic controls were enrolled. Corneal ECD and the distance between endothelium and the PIOL optic were evaluated in five different regions (central, nasal, superior, temporal, and inferior) using noncontact specular microscopy and rotating Scheimpflug imaging. RESULTS: In PIOL-implanted patients, significant differences between the ECD in the superior region, compared with the lowest ECD in any region, and the ECD of the central region, compared with that of the region with highest ECD, were evident. When PIOL-implanted eyes were divided based on time since operation, a significant difference was observed only in patients for whom at least 48 postoperative months had elapsed. In untreated myopic controls, the greatest ECD was observed at the superior cornea. The distance between the central corneal endothelium and PIOL was significantly longer than that of the peripheral locations. CONCLUSIONS: The extent of ECD decrease was not consistent throughout the cornea after implantation of an iris-fixated PIOL. Therefore, ECD measurement not only at the corneal center but also at midperipheral corneal locations, especially in the superior cornea, may be important in patients with iris-fixated PIOLs.