Tomographic Normal Values for Corneal Elevation and Pachymetry in a Hyperopic Population
|Joan T. Kim1, Michael Cortese2, Michael W. Belin3*, Renato Ambrosio Jr4 and Stephen S. Khachikian5|
|1University of Arizona College of Medicine, Department of Ophthalmology & Vision Science, Tucson, AZ, USA|
|2Albany TLC Laser Eye Center, Albany, New York, USA|
|3Professor of Ophthalmology & Vision Science University of Arizona College of Medicine & Southern Arizona Veterans Administration Healthcare System, Tucson, AZ, USA|
|4Instituto de Olhos Renato Ambrosio, Rio de Janeiro Corneal Tomography & Biomechanics Study Group, Rio de Janeiro, Brazil|
|5Black Hills Regional Eye Institute, Rapid City, SD, USA|
|Corresponding Author :||Michael W. Belin
4232 West Summer Ranch Place
Marana, AZ 85658, USA
E-mail: [email protected]
|Received November 15, 2010; Accepted February 11, 2011; Published February 14, 2011|
|Citation: Kim JT, Cortese M, Belin MW, Ambrosio R Jr, Khachikian SS (2011) Tomographic Normal Values for Corneal Elevation and Pachymetry in a Hyperopic Population. J Clinic Experiment Ophthalmol 2:130. doi:10.4172/2155-9570.1000130|
|Copyright: © 2011 Kim JT, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.|
|Related article at
Pubmed Scholar Google
Purpose: To establish a normative data base with respect to corneal pachymetry and elevation tomography appropriate for refractive surgery screening of hyperopic individuals.
Methods: 100 eyes of 51 consecutive hyperopic patients were examined with the Oculus Pentacam HR to determine corneal pachymetry and anterior and posterior elevation values at the apex and thinnest point. All patients were otherwise screened as normal and all principal meridians were hyperopic. Results were compared to a previously studied data base of myopic individuals from the same practice.
Results: The average corneal thickness at the apex and thinnest point was not significantly different between the hyperopic and myopic groups (P>0.05 at both locations). The mean anterior elevation at the apex was0.4 ± 1.9 µm in the hyperopic group vs. 1.6 ± 1.3 µm in the myopic group (P<0.001). The mean anterior elevation at the thinnest point was-0.1 ± 2.2 µm in the hyperopic group vs. 1.7 ± 2.0 µm in the myopic group (P<0.001). The mean posterior elevation at the apex was5.7 ± 3.6 µm in the hyperopic group vs. 0.8 ± 3.0 µm in the myopic group (P<0.001). The mean posterior elevation at the thinnest point was10.6 ± 5.7 µm for the hyperopic group vs. 3.6 ± 4.1 µm for the myopic group (P<0.001). When adjusted for age, the posterior elevation changes remained statistically significant.
Conclusions: Hyperopic individuals exhibited greater variation in posterior tomographic elevation values than a comparable myopic group. Currently used data bases need to be adjusted for screening hyperopic individuals to reduce the number of false positives associated with using a myopic biased data set.