Corneal Collagen Crosslinking for Treatment of Keratoconus

Purpose: The aim of this study was to assess the effects of corneal collagen cross-linking (CXL) on uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), subjective refraction, corneal irregularity, anterior chamber depth (ACD), corneal thickness, and k-readings. Patients and Methods: Eighty-four eyes of 44 patients with keratoconus  were treated using corneal collagen cross-linking. UCVA, BCVA, and subjective refraction were evaluated preoperatively as well as 3 months and 4 years after treatment and corneal Orbscan results were evaluated preoperatively and 4 years after treatment. Comparisons were made using paired sample t tests and a P values less than 0.05 were considered statistically significant. Results: There was a significant reduction in the mean thickness of the thinnest point of the cornea from 462.24 ± 46.95 µm preoperatively to 454.36 ± 55.32 µm (P < 0.05) at the last follow-up. The mean maximum and mean minimum curvature values reduced significantly from 48.00  ± 4.02 D and 45.03  ± 2.88 D preoperatively to 47.56  ± 3.75 D (P < 0.05) and 44.64 ± 2.94 D (P < 0.001), respectively at the last follow-up, whereas the UCVA (P = 0.309), BCVA (P = 0.594), subjective spherical equivalent (P = 0.591), subjective cylindrical refraction (P = 0.522), irregularity at the 3 mm (P = 0.338) and 5 mm (P = 0.915) zone of the cornea, anterior chamber depth (P = 0.072), and central corneal thickness (P = 0.203) remained unchanged. There were no significant postoperative complications. Conclusion: Based on our results, treatment  of progressive keratoconus with CXL can effectively stabilize UCVA, BCVA, subjective spherical equivalent, subjective cylindrical refraction, corneal irregularity, central corneal thickness and anterior chamber depth while reducing keratometry. Keywords: Cornea, Keratoconus, Collagen Crosslinking.