Study Of Macular Function and Morphology After Transepithelial Accelerated Corneal Collagen Cross-linking in Progressive Keratoconus

Abstract

The aim of this work is to evaluate the effect of transepithelial accelerated cross-linking (Epi-on CXL) on the macular function and morphology in progressive keratoconus. The study included 25 patients with progressive keratoconus with age ranged between 18 and 32 years. Epi-On Accelerated CXL was done for all cases. Evaluation was performed 2 and 6 weeks postoperatively after transepithelial (Epi-on) accelerated CXL by Optical coherence tomography (OCT) and multifocal electroretinography (mf-ERG). The central foveal thickness (CFT) decreased from 165.1 ± 21.5 µm to 163.4 ± 24.2 µm 2 weeks postoperatively to 164.8 ± 23.9 µm 6 weeks postoperatively, with no statistically significant difference. The preoperative retinal response density (RRD) decreased in macular ring 1 (foveal area of 2.8 degrees) from 179.5 ± 52.1 nV/deg2 preoperatively to 134.7 ± 43.2 nV/deg2 and 146.7 ± 41.6 nV/deg2 in 2 and 6 weeks, respectively postoperatively with statistically significant difference (p = 0.012), while the other 4 rings showed statistically insignificant difference (p >0.05) .On the other hand, implicit time latency (Pl) showed statistically insignificant difference between preoperative and postoperative values (p >0.05) in all macular rings. There is a minimal change in macular morphology after Epi-on accelerated CXL in progressive keratoconus, however, no significant change in macular function without any structural changes in progressive keratoconus 6 weeks postoperatively. A longer follow-up period studies are recommended to provide more information.