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Epithelium-on corneal cross-linking treatment of progressive keratoconus: a prospective, consecutive study

Authors Khairy HA, Mohammed Marey H, Ellakwa AF

Received 10 January 2014

Accepted for publication 1 February 2014

Published 29 April 2014 Volume 2014:8 Pages 819—823


Checked for plagiarism Yes

Review by Single anonymous peer review

Peer reviewer comments 4

Hany A Khairy, Hatem M Marey, Amin Faisal Ellakwa

Ophthalmology Department, Menoufia University Hospitals, Menofia, Egypt

Purpose: To evaluate the outcome of collagen cross-linking (CXL) without corneal epithelial debridement in patients treated for progressive keratoconus for whom the standard epithelium-off treatment cannot be applied, as their central corneal thickness (CCT) is less than 400 µm.
Patients and methods: This was a prospective, uncontrolled, interventional study involving 32 eyes of 30 patients with progressive keratoconus and CCT of less than 400 µm. All patients received CXL treatment with application of riboflavin and exposure to ultraviolet light A for 30 minutes without corneal epithelial debridement. Patients were followed up to 12 months postoperatively. The main outcomes were changes in maximum-K reading, manifest refractive spherical equivalent, CCT, and best-corrected visual acuity (logarithm of minimum angle of resolution). Patients were also asked to report any pain or discomfort during the procedure.
Results: At the end of the 12-month follow-up, CCT showed no significant change: from 392±5.17 µm preoperatively to 390±4.45 µm (P=0.102). Maximum-K reading decreased significantly, from 49.19±2.30 D preoperatively to 46.96±6.03 D postoperatively (P<0.05). The mean manifest spherical equivalent showed no significant change: from 4.04±1.51 D preoperatively to 4.17±1.63 D postoperatively (P=0.110). Mean best-corrected visual acuity showed no significant change: from 0.29±0.12 preoperatively to 0.31±0.11 postoperatively (P=0.110).
Conclusion: Epithelium-on CXL exhibits potential as a method for treating patients with progressive keratoconus and CCT of less than 400 µm, in which the standard epithelium-off CXL cannot be applied. Over 12 months of follow-up, the epithelium-on CXL was safe and effective, with results comparable to that achieved with the epithelium-off technique in thicker corneas, and reduced rates of operative and postoperative discomfort.

Keywords: keratoconus, cross-linking, refractive surgery, epithelium

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