Comparison of Stratus OCT and GDx VCC in Detecting Localized Retinal Nerve Fiber Layer Defects

ABSTRACT

PURPOSE: To compare the abilities of optical coherence tomography (Stratus OCT) and scanning laser polarimetry with variable corneal compensation (GDx VCC) in detecting localized retinal nerve fiber layer (RNFL) defects of red free photography METHODS: Thirty six normal subject and 50 patients with localized RNFL defects were included in this study. Only one eye per subject was considered. The peripapillary RNFL was divided into 12 clock-hour sectors and localized RNFL defects were evaluated in these 12 sectors. To compare the diagnostic performance of Stratus OCT and GDx VCC based on the findings of red-free photography, we calculated the sensitivity, specificity, and area under the receiver operating characteristic curve (AUC) of each analyzer using a criterion of 1 > or = clock hours abnormal at the <5% level. RESULTS: The sensitivity (78.6%), specificity (94.4%), and AUC (0.872) of Stratus OCT were not significantly different from those of GDx VCC (83.3%, 94.4%, and 0.882, respectively) (McNemar test, p=0.75, 1.00, and 0.82, respectively). However, the sensitivity (64.0%) of Stratus OCT for superior RNFL defect was significantly lower than that (84.8%) for inferior defect (Fisher's exact test, p=0.02). CONCLUSIONS: The sensitivity of the sector average of Stratus OCT and the deviation map of GDx VCC were fair in discriminating localized RNFL defects, and the specificity of those were excellent. In addition, the diagnostic performance was not significantly different between two analyzers.