Detectability of Glaucomatous Changes Using SAP, FDT, Flicker Perimetry, and OCT

Abstract

To compare the detectability between glaucomatous visual field changes using standard automated perimetry (SAP), frequency doubling technology (FDT), short-wavelength automated perimetry (SWAP), and flicker perimetry and structural changes using optical coherence tomography (OCT). Fifty-nine eyes of fifty-nine patients with open-angle glaucoma, 24 eyes of 24 glaucoma suspects (GSs), and 40 eyes of 40 healthy age-matched subjects. All subjects underwent Humphrey visual field analyzer II 24-2 full threshold (SAP), Swedish interactive threshold algorithm-SWAP, FDT (30-1, 30-5, 24-2-1, 24-2-5), flicker perimetry on Octopus 311 (4-zone probability 38S), and Stratus OCT [fast retinal nerve fiber layer thickness (NFLT) and fast optic disc]. To evaluate the visual field, FDT and flicker used the number of abnormal points, whereas SAP used mean deviation (MD) and SWAP used both the number of abnormal points and MD. The areas under the receiver operating characteristic curves [area under the curve (AUCs)] and sensitivities at fixed specificities were used to assess the detectability of glaucoma. The AUC for FDT 30-1, 30-5, 24-2-1, 24-2-5, flicker perimetry, SWAP (MD), and SWAP (number of abnormal points) were 0.95, 0.94, 0.88, 0.89, 0.99, 0.88, and 0.88 in the early glaucoma group and 0.67, 0.69, 0.65, 0.70, 0.80, 0.64, and 0.66 in the GS group, respectively. In the early glaucoma and GS groups, all OCT parameters had an AUC >0.81 except the disc area parameter. Especially, average NFLT had the highest AUC of 0.94 in the OCT parameters. FDT, SWAP, flicker perimetry, and OCT are all useful methods for discriminating between healthy eyes and eyes with early glaucoma. Among all 10 OCT parameters, NFLT has the highest sensitivity for detecting early glaucomatous changes in GS patients.