Corneal endothelial changes after accelerated corneal collagen cross-linking in keratoconus and postLASIK ectasia

PURPOSE: The purpose of this study was to evaluate the effects of accelerated cross-linking (CXL) on corneal endothelium in keratoconus and postlaser-assisted in situ keratomileusis (LASIK) ectasia. DESIGN: This study is a prospective nonrandomized controlled study. SETTING: This study was conducted in Mansoura Ophthalmic Center (Mansoura University) and Al-Mostakbal Ophthalmic Center, Mansoura, Egypt. METHODS: In total, 40 eyes with progressive keratoconus and 10 eyes with postLASIK ectasia were subjected to an accelerated CXL (10 mW/cm(2) for 9 minutes). Qualitative and quantitative analyses of the corneal endothelial cells were conducted before CXL and 3, 6, and 12 months after CXL by using a specular microscope (Tomy EM-3000). RESULTS: There was a significant reduction in endothelial cell count particularly at 3 and 6 months postCXL. In addition, the coefficient of variance was also statistically significantly higher at 3 and 6 months postoperatively than the preCXL value. There was a slight change in the percentage of hexagonal cells. CONCLUSION: The use of accelerated CXL (10 mW/cm(2) for 9 minutes) has a transient negative impact on endothelial cell density and/or endothelial morphology.