Comparison of the Diagnostic Capability of the Heidelberg Retina Tomographs 2 and 3 for Glaucoma in the Indian Population

Purpose To compare the diagnostic capability of the Heidelberg Retina Tomograph (HRT) 2 and 3 (Heidelberg Engineering, GmBH, Dossenheim, Germany) for glaucoma in an Indian population. Design Evaluation of a diagnostic technology. Participants Ninety-eight glaucoma subjects and 79 normal controls. Methods All participants underwent imaging with HRT2. Heidelberg Retina Tomograph 2 examinations were exported to HRT3 software. The stereometric parameters of HRT2 and HRT3 were compared. The diagnostic capability of Moorfields Regression Analysis (MRA) in the HRT2, HRT3 with and without ethnicity correction, and Glaucoma Probability Score (GPS) of HRT3 were compared. Analysis was done with the borderline results of MRA and GPS considered as normal to derive the most specific criteria and as abnormal to derive the least specific criteria. Main Outcome Measures Sensitivity, specificity, and area under the receiver operating characteristic curve (AUC). Results On standard automated perimetry (SAP), the mean deviation (mean±standard deviation) of the glaucoma and normal groups were −7.3±6.7 dB and −0.4±1.1 dB, respectively ( P