title: Corneal, limbal, and conjunctival epithelial thickness from optical coherence tomography.
abstract: OBJECTIVE
  To compare human central corneal, limbal and bulbar conjunctival epithelial thickness in vivo using an Optical Coherence Tomographer (OCT).
  
  
  METHODS
  Thirteen healthy human subjects participated in this study. An OCT (Carl Zeiss, Meditec, Dublin, CA) was used to image central cornea, temporal corneo-scleral limbus and bulbar conjunctiva of the left eye. Two images were taken at each location. Thirty central measurements were averaged from each image for quantifying epithelial thickness.
  
  
  RESULTS
  In addition to the central cornea and limbal region, a band corresponding to bulbar conjunctival "epithelium" is apparent in OCT images, with respective thicknesses of 54.7 +/- 1.9 microm (mean +/- SD), 79.6 +/- 7.4 microm and 44.9 +/- 3.4 microm that are statistically significant different (repeated measures analysis of variance p < 0.01, post hoc test shows all p < 0.01).
  
  
  CONCLUSIONS
  This study demonstrates that it is possible to image the epithelial tissue in humans in vivo using optical coherence tomography, and in these subjects, the corneo-limbal epithelium is the thickest, while the bulbar conjunctival epithelium is the thinnest and the corneal epithelium has intermediate thickness.
authors.affiliation: Centre for Contact Lens Research, School of Optometry, University of Waterloo, Waterloo, Ontario, Canada.
authors.forename: Yunwei
authors.initials: Y
authors.lastname: Feng
authors.forename: Trefford L
authors.initials: TL
authors.lastname: Simpson
mesh_terms: D000328:Adult; D003228:Conjunctiva / Q000166:cytology*; D004847:Epithelial Cells / Q000166:cytology; D019573:Epithelium, Corneal / Q000166:cytology*; D005260:Female; D006801:Humans; D016850:Limbus Corneae / Q000166:cytology*; D008297:Male; D041623:Tomography, Optical Coherence / Q000379:methods*