Combined transepithelial phototherapeutic keratectomy and conventional photorefractive keratectomy followed simultaneously by corneal crosslinking for keratoconus: Cretan protocol plus

Abstract

To evaluate the visual, refractive, and topographic outcomes after combined transepithelial phototherapeutic keratectomy (PTK) and conventional photorefractive keratectomy (PRK) followed simultaneously by corneal crosslinking (CXL) for keratoconus. Vardinoyiannion Eye Institute of Crete, Faculty of Medicine, University of Crete, Heraklion, Crete, Greece. Prospective case series. Patients with progressive keratoconus had simultaneous conventional PRK followed by CXL; the corneal epithelium was removed using transepithelial PTK (Cretan protocol plus). The visual, refractive, and topographic outcomes and the endothelial cell density (ECD) were evaluated preoperatively and 1, 3, 6, and 12 months postoperatively. Forty-three patients (55 eyes) were enrolled. The mean uncorrected and corrected distance visual acuities improved significantly from 0.98±0.63 (SD) logarithm of minimum angle of resolution (logMAR) and 0.20 ± 0.23 logMAR preoperatively to 0.39 ± 0.35 logMAR (P < .001) and 0.08 ± 0.16 logMAR (P < .001) 12 months postoperatively, respectively. The mean spherical equivalent improved significantly from -4.67 ± 4.00 diopters (D) preoperatively to -2.24 ± 2.81 D (P < .001) at 12 months. The mean steep keratometry (K) and flat keratometry readings decreased significantly from 50.30 ± 5.00 D and 45.62 ± 3.10 D preoperatively to 46.27 ± 3.90 D (P < .001) and 43.46 ± 3.00 D (P < .001) 12 months postoperatively, respectively. No ECD alterations were observed throughout the follow-up (P > .05). Combined transepithelial PTK and conventional PRK followed simultaneously by CXL was effective in cornealstabilization and vision improvement in keratoconic patients.