Evaluation of Mooren's corneal ulcer by anterior segment optical coherence tomography

Abstract

BackgroundThis study evaluates the use of anterior segment optical coherence tomography (AS-OCT) to identify focal changes and inform surgical plans in eyes with Mooren's ulcer. MethodsA total of 18 eyes of 17 patients with Mooren's ulcer were examined prospectively using the AS-OCT system. ResultsOptical hyperreflectivity noted on AS-OCT images was in accordance with corneal ulceration, neovascularization, fibrovascular membranes, the junction of the native stromal bed, and the overlying lamellar corneal grafts. Focal corneal ectasia was observed in 13 eyes with a decrease in corneal thickness to ≤0.39 mm. There was a cut-off value of 0.39 mm in corneal thickness between the eyes with and without focal corneal ectasia in the thinned corneal area (Fisher = 0.383, χ2 = 14.873, P = 0.000). Based on the AS-OCT findings, six eyes were subjected to an individualized lamellar corneal graft. The thickness of the residual cornea after surgery was 47 ± 34 μm less than the presumed healthy corneal thickness before surgery (t = 3.376, P = 0.02). A small corneal perforation covered by a pseudopterygium in Mooren's ulcer was found through AS-OCT but undetectable by slit-lamp biomicroscopy. ConclusionsAS-OCT is a valuable non-contact technique for monitoring corneal thinning in Mooren's ulcer, and assisting surgical design. A decrease in peripheral corneal thickness to ≤0.39 mm may cause focal corneal ectasia.