Usefulness of Macular Thickness Derived from Spectral-Domain Optical Coherence Tomography in the Detection of Glaucoma Progression

Abstract

To assess the reproducibility of circumpapillary retinal nerve fiber layer thickness (cRNFLT) and total macular thickness (TMT) parameters using Cirrus spectral domain optical coherence tomography (SD-OCT) and to apply this information to investigate its ability to detect cases where visual field (VF) progression was noted on event-based analysis in the eyes with early glaucomatous VF loss. Intraclass correlation coefficient (ICC), coefficient of variation (COV), and intersession test-retest variability were calculated from the control group. The sensitivity and specificity of SD-OCT for the identification of progressive VF defects were tested on progressive and stable patients. All ICCs from cRNFLT and TMT measurements ranged from 94.8% to 99.0%. While average cRNFLT showed the lowest intersession COV (2.57%), the nasal-outer and superior-inner TMT sectors showed the lowest COV (0.96%). The sensitivities of Cirrus SD-OCT cRNFLT measurements ranged from 37.8% to 48.9%, while that of TMT measurement was 73.3% when tested at the 95% confidence interval (CI). The sensitivity for detecting progressive VF changes in the central 10° area improved to 84.8% with TMT measurement, while it remained unchanged with cRNFLT measurements. The agreement on progression detection between cRNFLT and TMT sector measurements was poor (κ = 0.072 for overall, and 0.102 for the central 10° area at 95% CI, respectively). Intersession measurements of both cRNFLT and TMT parameters with Cirrus SD-OCT showed excellent reproducibility. TMT parameters using Cirrus SD-OCT may be better than cRNFLT measurements in terms of detecting progressive VF loss. This sensitivity derived from TMT measurements increased when progressive VF loss occurred in the central 10° area.