Recovery of corneal sensitivity after collagen crosslinking with and without epithelial debridement in eyes with keratoconus

PurposeTo evaluate the changes in corneal sensitivity after corneal collagen crosslinking (CXL) with the epithelium off (epi-off) and with the epithelium on (epi-on) in eyes with keratoconus.DesignProspective interventional case series.SettingEye Clinic, A. Fiorini Hospital, Terracina (Latina), Rome, Italy.MethodsOn the basis of the corneal pachymetry at the area of topographic steepening, eyes treated with CXL were divided in 2 groups: those with a corneal thickness of 400 μm or more (epi-off) and those with a corneal thickness of less than 400 μm (epi-on). Corneal sensitivity was measured using a contact esthesiometer (Cochet-Bonnet) before treatment and 1 and 7 days and 1, 3, 6, 9, and 12 months after treatment.ResultsThe study evaluated 50 CXL-treated eyes in 50 patients (25 epi-on and 25 epi-off) from January 7, 2012, to December 15, 2012. In the epi-off group, corneal sensitivity was statistically significantly reduced for up to 3 months after CXL and gradually returned to normal levels. In the epi-on group, corneal sensitivity was statistically significantly reduced for up to 7 days but was not statistically significantly different from preoperative values at other measurement times. At 7 days, the corneal sensitivity was statistically significantly lower in the epi-off eyes than in the epi-on eyes.ConclusionsEpi-off and epi-on CXL both caused hypoesthesia, but corneal sensitivity subsequently recovered completely. The corneal hypoesthesia was more pronounced in eyes in which the epi-off technique was used, and the recovery time was shorter for eyes treated using epi-on CXL.Financial DisclosureNo author has a financial or proprietary interest in any material or method mentioned.