The utility of contact lens-assisted corneal cross-linking (CACXL) in progressive keratoconus patients with thin corneas.

Abstract

To evaluate efficacy and safety of contact lens-assisted corneal cross-linking (CACXL) among progressive keratoconus patients with thin corneas. Private eye hospital. Cross-sectional study. Thirty-six eyes of 36 consecutive patients with progressive keratoconus and thinnest corneal thickness of 380-400 µm after epithelium removal were included. CACXL was performed based on use of a dextran-free isotonic (>0.1%) riboflavin solution with hydroxypropyl methylcellulose (HPMC, 1.1%) after epithelial removal and placement of a riboflavin-soaked contact lens without an ultraviolet filter on the cornea and ultraviolet irradiance. Data on best distance corrected (CDVA) and uncorrected (UDVA) visual acuity, manifest sphere (D), manifest cylinder (D), K1 (D), K2 (D), mean keratometry (D) and Kmax (D) values, endothelial cell count and mean depth of demarcation line were recorded preoperatively and at the postoperative 1-year. Post-operative 1-year data revealed significant increases in UDVA (0.23 ± 0.15 vs. 0.17 ± 0.13 D, p < 0.001) and CDVA (0.44 ± 0.18 vs. 0.36 ± 0.17 D, p < 0.001) values and a significant reduction in the mean Kmax (from 56 ± 3.3D to 55 ± 3.2 D, p < 0.001), K2 (from 49.7 ± 3.2 D to 49.52 ± 3.11 D, p = 0.049), manifest sphere (from -1.93 ± 2.21 D to -1.55 ± 2.02 D, p = 0.001) and manifest cylinder (from -2.83 ± 1.67 D to -2.39 ± 1.36 D, p < 0.001) values along with a similar endothelial cell count. The mean depth of demarcation line was mean 230 (SD17.05, range 200 to 262) at postoperative 1-month. Our findings indicate favourable 1-year postoperative outcome of CACXL in progressive keratoconus patients with thin cornea in terms of improved visual acuity and keratectasia status as well as endothelial safety.