Spectral-Domain Optical Coherence Tomography for Detection of Localized Retinal Nerve Fiber Layer Defects in Patients With Open-Angle Glaucoma

Abstract

To evaluate and compare time-domain (Stratus) and spectral-domain (Cirrus; both Carl Zeiss Meditec, Dublin, California) optical coherence tomography (OCT) for the detection of localized retinal nerve fiber layer (RNFL) defects in patients with open-angle glaucoma. Patients with localized RNFL defects and age-matched normal control participants were consecutively enrolled from July 1 to December 31, 2008. Sixty-six eyes from 66 patients and 66 eyes from 66 normal controls were imaged with Stratus OCT (fast RNFL scan mode) and Cirrus OCT (optic disc cube mode). The ability to detect the RNFL defect by using quadrant clock-hour maps from both OCTs and a Cirrus OCT deviation map were compared with red-free RNFL photography, which is the criterion standard for visualizing RNFL defects. The Cirrus OCT deviation map exhibited significantly higher overall sensitivity (92.42%) in detecting the RNFL defects compared with the other maps, which were derived from a 3.46-mm-diameter peripapillary cross-sectional RNFL scan of both OCTs (P < .001). The Cirrus OCT quadrant map had a higher specificity; however, it was not statistically significant (P = .07). Compared with the other maps, the Cirrus OCT derivation map had the lowest cutoff angle for the width (10.69°) of the RNFL defect. The deviation map from Cirrus OCT was more sensitive in detecting RNFL defects than the clock-hour and quadrant maps derived from cross-sectional peripapillary RNFL measurements by Stratus and Cirrus OCTs. The ability to detect localized RNFL defects on clock-hour or quadrant RNFL maps did not significantly differ between Stratus OCT and Cirrus OCT.