LAUSR

OBJECTIVE Using anterior segment optical coherence tomography (AS-OCT), we investigated the epithelial thickness (ET) of the central cornea and limbal regions in patients with limbal stem cell deficiency (LSCD) as a diagnostic and staging parameter. DESIGN Prospective, cross-sectional study METHODS: The central corneal epithelium thickness (CET) and maximum limbal epithelium thickness (mLET) were measured in the superior, inferior, nasal, and temporal limbus on AS-OCT images of the normal and eyes with LSCD. CET was obtained by 1-point (OCT-CET1) and 3-point measurement (OCT-CET3). The values of OCT-CET1 and OCT-CET3 were compared to the CET obtained with in vivo confocal microscopy (IVCM-CET). RESULTS Sixty-eight eyes of 50 patients with LSCD and 52 eyes of 34 normal subjects were included. The mean (±SD) OCT-CET3 was 55.0±3.0 μm (range, 50.6-62.0 μm) in the control group and 41.6±10.8 μm (range, 0-56.3 μm) in the LSCD group (P<0.001). OCT-CET3 had a better correlation with IVCM-CET (r=0.91) than did OCT-CET1 (r=0.87, P=0.001). The degree of reduction in OCT-CET3 increased in more advanced clinical stages of LSCD (all P<0.001). The OCT-CET3 cutoff value that suggests LSCD was 46.6 μm. Compared with the control group, the LSCD group had decreases in mLET in all four limbal regions (all P <0.001). The sensitivity and specificity of OCT-CET3 is the highest among all mLET in detecting LSCD. CONCLUSIONS Both CET and mLET were thinner in patients with LSCD than in normal subjects. OCT-CET3 appears to be a reliable parameter to confirm LSCD when there is clinical suspicion.