Document Detail


Thickness mapping of the cornea and epithelium using optical coherence tomography.
MedLine Citation:
PMID:  18832971     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
PURPOSE: To measure corneal and epithelial thickness across four meridians using Optical Coherence Tomography (OCT) and to compare these measurements between normal non-lens wearers (NLW), rigid gas permeable (RGP) lens wearers, and RGP-wearing keratoconics (KC). METHODS: Both eyes of 60 subjects were measured (20 NLW, nine female:11 male, 27.6 +/- 5.9 years; 20 RGP, 20 female, 23.9 +/- 7.6 years; and 20 KC, seven female:13 male, 32.4 +/- 8.1 years). A customized fixation target employing LEDs in eight directions of gaze was attached to the OCT and corneal images obtained. Raw OCT scans were analyzed to yield values for corneal and epithelial thickness and color-coded maps were compiled. RESULTS: Central corneal thickness (CCT) was thinnest in KC (447 +/- 68 microm) and similar between RGP (518 +/- 32 microm; pKC < 0.001) and NLW (517 +/- 21 microm) (p(KC) < 0.001 NLW pRGP > 0.05). Peripheral corneal thickness in NLW was thickest in the superior temporal and thinnest in the inferior (I) regions (superior temporal(thickest) vs. I(thinnest) p < 0.001). Central epithelial thickness was thinnest in KC (44 +/- 7 microm), followed by RGP (50 +/- 4 microm), then NLW (54 +/- 2 microm) (pKC < 0.001 NLW p(RGP) < 0.05). Central epithelial thickness in the KC group was significantly thinner than in the RGP group (p < 0.001). In the NLW group, peripheral epithelial thickness was thicker (63 +/- 5 microm) than central (p < 0.001) and was thickest in the superior (S) region and thinnest in the inferior (I) region (S(thickest) vs. I(thinnest) p < 0.001). KC epithelium was thinnest in the inferior temporal meridian (42 +/- 5 microm). CONCLUSIONS: Thickness of the normal cornea and epithelium was greatest in the superior region. In all groups, the inferior cornea and epithelium was thinnest, and to a greater extent in the KC group.
Authors:
Sameena Haque; Lyndon Jones; Trefford Simpson
Publication Detail:
Type:  Comparative Study; Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Optometry and vision science : official publication of the American Academy of Optometry     Volume:  85     ISSN:  1538-9235     ISO Abbreviation:  Optom Vis Sci     Publication Date:  2008 Oct 
Date Detail:
Created Date:  2008-10-03     Completed Date:  2008-12-22     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  8904931     Medline TA:  Optom Vis Sci     Country:  United States    
Other Details:
Languages:  eng     Pagination:  E963-76     Citation Subset:  IM    
Affiliation:
Centre for Contact Lens Research, School of Optometry, University of Waterloo, Waterloo, Ontario, Canada. sameena.haque-khan@cibavision.com
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Adult
Contact Lenses*
Cornea / pathology*
Corneal Stroma / pathology
Corneal Topography / methods*
Epithelium, Corneal / pathology*
Equipment Design
Female
Humans
Keratoconus / pathology*,  rehabilitation
Male
Tomography, Optical Coherence* / instrumentation
Young Adult

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Visualizing the limits of low vision in detecting natural image features.
Next Document:  Binocular vision changes in university students: a 3-year longitudinal study.