Changes in Corneal Keratometry Readings after Corneal Collagen Cross-Linking Using Alcohol in Keratoconus Patients

ABSTRACT

PURPOSE: To evaluate the changes in corneal keratometry (K) readings after corneal collagen cross- linking (CXL) using 20% alcohol in primary keratoconus and keratectasia after refractive surgery. METHODS: Twelve eyes of 10 patients with primary keratoconus and 3 eyes of 3 patients with keratectasia after refractive surgery were included in the present study. Best-corrected visual acuity (BCVA) and mean K, corneal astigmatism by corneal topography, and mean K, corneal astigmatism, and spherical equivalent (SE) by auto refractometer were evaluated at baseline, and 6 months postoperatively. Eight eyes of 7 patients were also evaluated 1 year postoperatively. RESULTS: Mean BCVA improved from log MAR 0.66 +/- 0.50 to log MAR 0.55 +/- 0.58 (p = 0.100) at 6 month after CXL. In corneal topography, mean K significantly decreased from 50.04 +/- 5.88 D to 49.18 +/- 6.15 D (p = 0.019), and corneal astigmatism slightly decreased from 5.33 +/- 4.47 D to 5.29 +/- 4.88 D (p = 0.755) at 6 months after CXL. According to the auto refractometer, mean K significantly decreased from 48.53 +/- 5.94 D to 47.95 +/- 5.79 D (p = 0.038), corneal astigmatism significantly decreased from 3.95 +/- 2.54 D to 3.52 +/- 2.40 D (p = 0.010), and SE significantly decreased from -6.25 +/- 3.45 D to -5.40 +/- 2.91 D (p = 0.037) at 6 months after CXL. Significant mean K and corneal astigmatism decreases in topography were also observed at 1 year after CXL. Complications related to CXL were not observed. CONCLUSIONS: CXL using 20% alcohol appears to be a safe and promising treatment modality with less corneal stromal damage in progressive primary keratoconus and keratectasia after refractive surgery.