Corneal Elevation Values in Normal Eyes, forme fruste Keratoconus and Keratoconus at Different Stages Measured by Scheimpflug Imaging
Luis Izquierdo, Maria A Henriquez, David Dañin
Citation Information :
Izquierdo L, Henriquez MA, Dañin D. Corneal Elevation Values in Normal Eyes, forme fruste Keratoconus and Keratoconus at Different Stages Measured by Scheimpflug Imaging. Int J Kerat Ect Cor Dis 2014; 3 (1):36-39.
To compare corneal elevation values in normal eyes, forme fruste keratoconus (FFKC) and different stages of keratoconus using Scheimpflug imaging.
Materials and methods
This prospective, comparative study included 267 eyes (107 normal eyes, 21 FFKC and 139 keratoconus). Keratoconic eyes were divided into four groups according to keratometry values. Maximum posterior elevation (PE) above the (best fit sphere (BFS) at the central 5 mm were measured using the Pentacam (Oculus Optikgeräte GmbH). Receiver operating characteristic curves were used to determine the test's overall predictive accuracy and to identify optimal cutoff points to discriminate between the groups.
Results
PE had the smallest values in normal eyes and increased in FFKC and each progressive stage of keratoconus. Mean PE was 9.98 ± 5.33 µm in normal eyes, 18.09 ± 9.23 µm in FFKC and 24.97 µm ± 15.89, 37.82 ± 18.64, 46.82 ± 21.41 and 66.07 ± 39.09, in keratoconus stage I, II, III and IV respectively.
Conclusion
Posterior elevation values increased according to the severity of keratoconus disease. PE can be used as indicator of keratoconus progression.
How to cite this article
Henriquez MA, Izquierdo L Jr, Dañin D. Corneal Elevation Values in Normal Eyes, forme fruste Keratoconus and Keratoconus at Different Stages Measured by Scheimpflug Imaging. Int J Kerat Ect Cor Dis 2014;3(1):36-39.
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