Combined Transepithelial Phototherapeutic Keratectomy and Corneal Collagen Cross-Linking for Progressive Keratoconus

• Published in: Ophthalmology (Rochester, Minn.) Vol. 119; no. 9; pp. 1777 - 1784
• Main Authors: Kymionis, George D., MD, PhD, Grentzelos, Michael A., MD, Kounis, George A., PhD, Diakonis, Vasilios F., MD, Limnopoulou, Aliki N., MD, Panagopoulou, Sophia I., PhD
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Inc 01.09.2012; Elsevier
• Subjects: Adult; Biological and medical sciences; Collagen - metabolism; Combined Modality Therapy; Corneal Stroma - metabolism; Cross-Linking Reagents - therapeutic use; Debridement - methods; Disease Progression; Diseases of cornea, anterior segment and sclera; Epithelium, Corneal - surgery; Female; Humans; Keratoconus - drug therapy; Keratoconus - metabolism; Keratoconus - physiopathology; Keratoconus - surgery; Lasers, Excimer - therapeutic use; Male; Medical sciences; Microscopy, Confocal; Miscellaneous; Ophthalmology; Photochemotherapy; Photorefractive Keratectomy; Photosensitizing Agents - therapeutic use; Prospective Studies; Riboflavin - therapeutic use; Ultraviolet Rays; Visual Acuity - physiology; Young Adult; Progressive; Eye disease; Cornea; Keratoconus; Collagen; Keratopathy; Ophthalmology; Anterior segment disease; Photorefractive keratectomy
• ISSN: 0161-6420; 1549-4713
• DOI: 10.1016/j.ophtha.2012.03.038

Purpose To compare the outcomes of corneal collagen cross-linking (CXL) for the treatment of progressive keratoconus using 2 different techniques for epithelial removal: transepithelial phototherapeutic keratectomy (t-PTK) versus mechanical epithelial debridement. Design Prospective, comparative, interventional case series. Participants Thirty-four patients (38 eyes) with progressive keratoconus were enrolled. Methods All patients underwent uneventful CXL treatment. Sixteen patients (19 eyes) underwent epithelial removal using t-PTK (group 1) and 18 patients (19 eyes) underwent mechanical epithelial debridement using a rotating brush (group 2) during CXL treatment. Visual and refractive outcomes were evaluated along with corneal confocal microscopy findings preoperatively and at 1, 3, 6, and 12 months postoperatively. Main Outcome Measures Uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), manifest refraction, and keratometry readings. Results No intraoperative or postoperative complications were observed in any of the patients. In group 1, logarithm of the minimum angle of resolution mean UDVA and mean CDVA improved from 0.99±0.71 and 0.30±0.26 preoperatively to 0.63±0.42 ( P = 0.02) and 0.19±0.18 ( P = 0.008) at 12 months postoperatively, respectively. In group 2, neither mean UDVA nor mean CDVA demonstrated a significant improvement at 12 months postoperatively ( P >0.05). In group 1, mean corneal astigmatism improved from −5.84±3.80 diopters (D) preoperatively to −4.31±2.90 D ( P = 0.015) at the last follow-up, whereas in group 2 there was no significant difference at the same postoperative interval ( P >0.05). No endothelial cell density alterations were observed throughout the follow-up period for both groups ( P >0.05). Conclusions Epithelial removal using t-PTK during CXL results in better visual and refractive outcomes in comparison with mechanical epithelial debridement. Financial Disclosure(s) The authors have no proprietary or commercial interest in any of the materials discussed in this article.