Abstract
Purpose: :
To report and to predict long-term endothelial celloutcomes after iris fixated phakic intraocularlens implantation for the correction of high refractive errors.
Methods: :
Retrospective,non randomized study of patient who underwent surgery between January,2000 and December,2009. Wide-field specular microscopy was used to assess the endothelial cell density in the central cornea. Postoperative complications were recorded.To predict long-term endothelial cell density, 2 joint regression models were fitted on ECD to individuals with at least 2 ECD measurement in time.Model-predicted parameters for endothelial cell density were obtained for each patient and were used in a Kaplan-Meier method plot for predicting corneal endothelium survival.
Results: :
78 eyes of 43 patients were examined. The mean follow-up time was68 ±32 months. The mean preoperative and final endothelial cell density were,respectively, 2860 ±359 cells/mm² and 2167 ±545 cells/mm². The mean endothelial cell loss at the end of follow up was 25±15%. Two model were obtained, linear and biphasic. First phase of biphasic model showed a loss probably due to surgical trauma, even if surgery was performed by two experienced surgeons. Second phase is a progressive endothelial cell loss. Twenty years after surgery both models showed a percentage of eyes with ECD superior to 500 cells/mm² inferior to 50%.
Conclusions: :
Long-term reports are necessary to evaluate the timing of IOL explantation.
Keywords: cornea: endothelium • refractive surgery: phakic IOL