title: Epithelial Thinning in Limbal Stem Cell Deficiency.
abstract: OBJECTIVE
  To investigate the epithelial thickness in the cornea and limbus in limbal stem cell deficiency (LSCD) by using in vivo laser scanning confocal microscopy.
  
  
  METHODS
  Cross-sectional comparative study.
  
  
  METHODS
  Confocal images of 48 eyes of 35 patients with LSCD collected by the Heidelberg Retina Tomograph III Rostock Corneal Module Confocal Microscope from 2010 to 2014 were analyzed. Volume Z-scans of the central cornea and the superior, nasal, inferior, and temporal limbus were included in the analysis. Eleven normal eyes served as control. Epithelial thickness in all locations was measured by 2 independent observers.
  
  
  RESULTS
  The mean epithelial layer thickness was 48.6 ± 2.3 μm in the central cornea and 63.7 ± 11.3 μm in the limbus in the control. Compared with the epithelial thickness in normal control, the epithelial thickness in LSCD patients was reduced by an average of 20.2% in the central cornea and 38.5% in the limbus (all P < .05). The mean corneal epithelial thickness in patients with LSCD reduced 7.6%, 20.8%, and 61.3% in the early, intermediate, and late stage, respectively, compared to the control. In the limbus, the overall epithelial thickness decreased 30.0%, 39.7%, and 62.8% in the early, intermediate, and late stage of LSCD, respectively (all P < .05). Epithelial thinning correlated with the severity of LSCD in both cornea and limbus. In eyes with sectoral LSCD, a similar degree of epithelial thinning was also detected in the clinically unaffected limbal regions.
  
  
  CONCLUSIONS
  Both corneal and limbal epithelia become progressively thinner in LSCD. Epithelial thickness could be used as a diagnostic measure of LSCD.
authors.affiliation: Cornea Division, Stein Eye Institute, University of California, Los Angeles, Los Angeles, California; David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California.
authors.forename: Eric H
authors.initials: EH
authors.lastname: Chan
authors.affiliation: Cornea Division, Stein Eye Institute, University of California, Los Angeles, Los Angeles, California.
authors.forename: Luxia
authors.initials: L
authors.lastname: Chen
authors.affiliation: Department of Biostatistics, Fielding School of Public Health, University of California, Los Angeles, Los Angeles, California.
authors.forename: Fei
authors.initials: F
authors.lastname: Yu
authors.affiliation: Cornea Division, Stein Eye Institute, University of California, Los Angeles, Los Angeles, California. Electronic address: deng@jsei.ucla.edu.
authors.forename: Sophie X
authors.initials: SX
authors.lastname: Deng
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003316:Corneal Diseases / Q000175:diagnosis*; D003430:Cross-Sectional Studies; D019573:Epithelium, Corneal / Q000473:pathology*; D005260:Female; D006801:Humans; D016850:Limbus Corneae / Q000473:pathology*; D008297:Male; D018613:Microscopy, Confocal; D008875:Middle Aged; D009929:Organ Size; D012372:ROC Curve; D013234:Stem Cells / Q000473:pathology*; D055815:Young Adult