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Abstract #12431 Published in IGR 7-2
Ratio of hemi-papillary rim volumes and glaucoma diagnosis with Heidelberg retina tomograph
Chen EJournal of Glaucoma 2005; 14: 206-209
PURPOSE: To test if inclusions of the ratios of hemi-papillary parameters in the discriminant function could improve the precision in glaucoma diagnosis with the Heidelberg Retina Tomograph (HRT). MATERIALS AND METHODS: Papillary topographs obtained with HRT were reviewed in 202 patients with primary open angle glaucoma, exfoliation glaucoma, pigment glaucoma, ocular hypertension, or glaucoma heredity. A hemi-papillary HRT parameter was obtained by horizontally dividing the optic nerve head image into two halves. A ratio was calculated for each of the HRT parameters with the greater value of the two halves as numerator. The hemi-papillary HRT parameters, together with the ordinary HRT papillary parameters, were evaluated with discriminant analysis to estimate their significance in the glaucoma diagnosis. RESULTS: The new discriminant function is: the ratio of hemi-papillary rim volumes *1.110 + cup/disc area ratio *2.560 + rim area *-1.674 -0.040, established in a group of 66 eyes. The sensitivity of this discriminant function was 84.0%, and the specificity 92.7% in this group. When this discriminant function was applied to a test group of 74 eyes the sensitivity was 89.2% and specificity 87.0%. The sensitivity with the new discriminant function was 81.8% at the early stage of glaucoma and 100.0% at moderate or advanced glaucoma damage. CONCLUSION: The new discriminant function, including the ratio of hemi-papillary rim volumes, the total rim area, and the cup-disc area ratio improves the precision in glaucoma diagnosis with HRT.
Dr. E. Chen, Glaucoma Service, St. Erik's Eye Hospital, Karolinska Institute, Stockholm, Sweden. enping.chen@sankterik.se
Classification:
6.9.1 Laser scanning (Part of: 6 Clinical examination methods > 6.9 Computerized image analysis)
