Correlation of the Corneal Collagen Cross-Linking Demarcation Line Using Confocal Microscopy and Anterior Segment Optical Coherence Tomography in Keratoconic Patients

PURPOSE: To evaluate and compare the depth of the corneal stromal demarcation line after corneal collagen cross-linking (CXL) using 2 different methods: confocal microscopy and anterior segment optical coherence tomography (AS OCT). DESIGN: Prospective, comparative, interventional case series. METHODS: Seventeen patients (18 eyes) with progressive keratoconus were enrolled. All patients underwent uneventful CXL treatment according to the Dresden protocol. One month after surgery, corneal stromal demarcation line depth was measured in all patients by 2 independent observers using confocal microscopy and AS OCT. RESULTS: Mean corneal stromal demarcation line depth measured using confocal microscopy by the first observer was 306.22 +/- 51.54 mu m (range, 245 to 417 mu m) and that measured by the second observer was 303.5 +/- 46.98 mu m (range, 240 to 390 mu m). The same measurements using AS OCT were 300.67 +/- 41.56 mu m (range, 240 to 385 mu m) and 295.72 +/- 41.01 mu m (range, 228 to 380 mu m) for the first and second observer, respectively. Pairwise comparisons did not reveal any statistically significant difference between confocal microscopy and AS OCT measurements for both observers (P = .3219 for the first observer and P = .1731 for the second observer). CONCLUSIONS: Both confocal microscopy and AS OCT have similar results in evaluating the depth of the corneal stromal demarcation line after CXL. (C) 2014 by Elsevier Inc. All rights reserved.