Quantitative anatomical differences in central corneal thickness values determined with scanning-slit corneal topography and noncontact specular microscopy.

Department of Anatomy and Human Embryology, Faculty of Medicine, University of Valencia, Spain.
Cornea (Impact Factor: 1.75). 03/2006; 25(2):203-5. DOI: 10.1097/01.ico.0000176605.72129.2c
Source: PubMed

ABSTRACT This study was designed to analyze the differences in central corneal thickness values determined with noncontact specular microscopy and scanning-slit corneal topography. The measurements were performed on the same eye.
We analyzed the central corneal thickness values of 93 patients (n = 93) by means of noncontact specular microscopy (Topcon SP-2000P noncontact specular microscope, Topcon Corp., Tokyo, Japan) and scanning-slit corneal topography (Orbscan Topography System II, Orbscan Inc., Salt Lake City, UT). One experienced physician performed 3 consecutive central corneal thickness measurements with both devices.
The central corneal thickness values obtained by means of Orbscan pachymetry were 17 +/- 2.7 (range, 12-24) microm greater. A significant correlation was observed between scanning-slit corneal topography and noncontact specular microscopy (Pearson correlation coefficient, r = 0.976; P < 0.001).
Researchers should know of the existence of this difference between noncontact specular microscopy and Orbscan pachymetry when interpreting central corneal thickness values.

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