Three-Dimensional Imaging of Macular Inner Structures in Glaucoma by Using Spectral-Domain Optical Coherence Tomography

Abstract

To profile macular thickness changes in glaucoma by using three-dimensional spectral-domain optical coherence tomography (3D-SD-OCT). The study included 30 eyes with suspected glaucoma and preperimetric glaucoma (SGPPG) and 35 healthy eyes. The macular thickness, including those of the total retina, nerve fiber layer (NFL), and combined inner retinal layers (IRLs)-NFL+ganglion cell layer (GCL)+inner plexiform layer (IPL)-was measured by 3D-SD-OCT raster scans in a 6 mm(2) region. The average and sectoral thicknesses were calculated on an Early Treatment of Diabetic Retinopathy Study (ETDRS) chart and a ETDRS chart with a 45° rotation (glaucoma sector chart, GSC). The mean IRL thickness was significantly less in the SGPPG eyes than in the healthy eyes, but the mean total retinal and macular NFL thicknesses were not. In the SGPPG eyes, the IRLs were thinner in the outer macula than in the inner macula, in the inferior hemisphere than in the superior hemisphere, and in the temporal hemisphere than in the nasal hemisphere. The significantly thinned sectors were nearly identical on the GSC but only slightly overlapped on the ETDRS chart. The IRLs in the inferior temporal outer sector (GSC) had the greatest area under the receiver operating characteristic curve, which was significantly greater than those for the IRLs over the entire macula, inferior hemiretinal region, and inferior outer hemicircular region (macular subfields), and that for the circumpapillary NFL in the inferior sectors (P = 0.001-0.036). Macular IRL thickness measured by using 3D-SD-OCT is useful for profiling macular atrophy in SGPPG.