Keratoconus diagnosis with optical coherence tomography-based ...

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of Wenzhou Medical College, Wenzhou, China. DESIGN: Cross-sectional ... University of Southern California, Los Angeles, California,. USA; Wenzhou Medical ...
ARTICLE

Keratoconus diagnosis with optical coherence tomography–based pachymetric scoring system Bing Qin, MD, Shihao Chen, MD, Robert Brass, MD, Yan Li, PhD, Maolong Tang, PhD, Xinbo Zhang, PhD, Xiaoyu Wang, MD, Qinmei Wang, MD, David Huang, MD, PhD

PURPOSE: To develop an optical coherence tomography (OCT) pachymetry map–based keratoconus risk scoring system. SETTINGS: Doheny Eye Institute, University of Southern California, Los Angeles, California, and Brass Eye Center, New York, New York, USA; Department of Ophthalmology, Affiliated Eye Hospital of Wenzhou Medical College, Wenzhou, China. DESIGN: Cross-sectional study. METHODS: Fourier-domain OCT was used to acquire corneal pachymetry maps in normal and keratoconus subjects. Pachymetric variables were minimum, minimum median, superior–inferior (S–I), superonasal–inferotemporal (SN–IT), and the vertical location of the thinnest cornea (Ymin). A logistic regression formula and a scoring system were developed based on these variables. Keratoconus diagnostic accuracy was measured by the area under the receiver operating characteristic (ROC) curve. RESULTS: One hundred thirty-three eyes of 67 normal subjects and 82 eyes from 52 keratoconus subjects were recruited. The keratoconus logistic regression formula Z 0.543  minimum C 0.541  (S–I) 0.886  (SN–IT) C 0.886  (minimum–median) C 0.0198  Ymin. The formula gave better diagnostic power with the area under the ROC than the best single variable (formula Z 0.975, minimum Z 0.942; P