Ability of Scanning Laser Polarimetry (GDx) to Discriminate among Early Glaucomatous, Ocular Hypertensive and Normal Eyes in the Korean Population

ABSTRACT

We investigated the ability of the GDx-Nerve Fiber Analyzer (NFA) to discriminate between normal and early glaucomatous eyes among Korean individuals by reviewing the medical records of 217 consecutive subjects: 61 early glaucoma patients, 68 ocular hypertensive patients, and 88 normal subjects. GDx parameters were compared using ANOVA. The Receiver Operating Characteristics (ROC) curve for each GDx-NFA variable was used to diagnose each parameter, and Pearson correlation coefficients were calculated to assess the association between GDx-NFA parameters and visual field indices in early glaucoma. The best GDx parameters to discriminate between early glaucomatous and normal subjects were the number, maximum modulation, ellipse modulation and inferior ratio (i.e. area under the ROC curve > 0.8). A value for the Number of equal to or greater than 27 was optimal for detecting early glaucoma, with a sensitivity of 80.3% and specificity of 80.7%. In addition, symmetry was positively correlated with the corrected pattern standard deviation (CPSD) among visual field indices in early glaucoma.