Yeoun Sook Chun1, Woong Bae Yoon2, Kwang Gi Kim2, In Ki Park3. 1. Department of Ophthalmology, Chung-Ang University College of Medicine, Chung-Ang University Hospital, Seoul, South Korea. 2. Biomedical Engineering Branch, Division of Convergence Technology, National Cancer Center, Goyang, South Korea. 3. Department of Ophthalmology, Kyung Hee University College of Medicine, Kyung Hee University Hospital, Seoul, South Korea.
Abstract
PURPOSE: To validate a new objective digital image analysis technique to evaluate corneal staining. METHODS: One hundred photographs of corneal staining from various ocular surface diseases in 100 patients were quantified by a new strategy: a combination of the difference of Gaussians (DoG) edge detection for morphologic properties of corneal erosions and the red-green-blue (RGB) systems and hue-saturation-value (HSV) color model for detection of color. To enhance the image, we adopted a median filter, Otsu thresholding, and contrast-limited adaptive histogram equalization (CLAHE). To validate the diagnostic value of this new strategy, the same photographs were also graded by two independent clinicians using the Oxford scheme and the National Eye Institute/Industry (NEI)-recommended guidelines. The correlation between the average subjective grade and objective image analysis measurement was evaluated using the Pearson's correlation coefficient. RESULTS: The new algorithm showed a strong correlation with the clinical grading scale in the Oxford scheme and the NEI-recommended guidelines (R = 0.850 and 0.903, P < 0.001, respectively). The repeatability of the objective measurement was excellent (R = 0.994). CONCLUSIONS: The new algorithm showed excellent correlation with the traditional subjective clinical grading scales. It may be useful for objective assessment of corneal staining, independent of disease conditions. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.
PURPOSE: To validate a new objective digital image analysis technique to evaluate corneal staining. METHODS: One hundred photographs of corneal staining from various ocular surface diseases in 100 patients were quantified by a new strategy: a combination of the difference of Gaussians (DoG) edge detection for morphologic properties of corneal erosions and the red-green-blue (RGB) systems and hue-saturation-value (HSV) color model for detection of color. To enhance the image, we adopted a median filter, Otsu thresholding, and contrast-limited adaptive histogram equalization (CLAHE). To validate the diagnostic value of this new strategy, the same photographs were also graded by two independent clinicians using the Oxford scheme and the National Eye Institute/Industry (NEI)-recommended guidelines. The correlation between the average subjective grade and objective image analysis measurement was evaluated using the Pearson's correlation coefficient. RESULTS: The new algorithm showed a strong correlation with the clinical grading scale in the Oxford scheme and the NEI-recommended guidelines (R = 0.850 and 0.903, P < 0.001, respectively). The repeatability of the objective measurement was excellent (R = 0.994). CONCLUSIONS: The new algorithm showed excellent correlation with the traditional subjective clinical grading scales. It may be useful for objective assessment of corneal staining, independent of disease conditions. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.
Authors: Vatinee Y Bunya; Min Chen; Yuanjie Zheng; Mina Massaro-Giordano; James Gee; Ebenezer Daniel; Ryan O'Sullivan; Eli Smith; Richard A Stone; Maureen G Maguire Journal: JAMA Ophthalmol Date: 2017-10-01 Impact factor: 7.389