Corneal Endothelial Tolerance After Iris-Fixated Phakic Intraocular Lens Implantation: A Model to Predict Endothelial...

To evaluate the long-term endothelial tolerance of iris-fixated phakic intraocular lenses (pIOLs) over a 10-year period, to identify predictive factors for endothelial decompensation, and to develop a model to predict endothelial cell survival after pIOL implantation.

This retrospective study included 130 eyes in 60 patients who underwent pIOL implantation for correction of high myopia from January 2003 to October 2012 at Edouard Herriot Hospital in Lyon, France. Endothelial cell densities (ECDs) were measured using specular microscopy before and biannually after pIOL implantation. Best-corrected visual acuity was measured before and 6 months after pIOL implantation. The annual postoperative decrease in ECD was estimated using a mixed linear regression model with a random intercept. Patient and eye characteristics were introduced into the model to quantify their effect on ECD change. The main outcome measures were annual postoperative reduction of ECD and best-corrected visual acuity.

The preoperative ECD was 2770 ± 265 cells/mm (2134-3200 cells/mm). The ECD decreased by 1.83%, on average (95% confidence interval, 1.54-2.10), during the first postoperative year. Thereafter, the mean decrease in annual ECD was estimated to be 0.87% (95% confidence interval, 0.78-0.95). For a cell number of 3500, 3000, 2500, and 2000, the number of years required to reach the threshold of 1500 cells/mm was estimated to be approximately 96, 78, 57, and 32 years, respectively. No predictive factors for endothelial decompensation were identified.

pIOL implantation is a safe surgical means to correct high myopia in phakic patients without compromising corneal endothelium survival.