Influence of standard corneal cross-linking in keratoconus patients on macular profile

Purpose: To determine the effect of corneal cross-linking (CXL) on retinal structure and function. Methods: The current study was conducted on 42 eyes of 21 patients with keratoconus (KCN) who were candidates for CXL due to disease progression. The Optovue optical coherence tomography (OCT) (Optovue Inc., Fremont, USA) from macula and multifocal electroretinography (mERG) were performed on all patients prior to surgery and at 1- and 6- month follow-up. Structural and functional parameters of macula including retinal thickness in OCT, and amplitude and latency of electroretinogram were compared between eyes that underwent surgery and control fellow eyes during the study period. Results: A statistically significant increase in central foveal, foveal, parafoveal, and perifoveal thickness was observed at 1-month follow-up. The changes were non-significant at 6 months. Although a statistically significant reduction in amplitude and increase in latency in both rings 2 and 3 were observed at 1 month in mERG, only amplitude changes in ring 2 remained significant at 6 months. Conclusion: Transient anatomical and functional alterations following CXL were observed in the current study.