Segmental Analysis of Macular Layers in Patients With Unilateral Primary Open-Angle Glaucoma

To measure the thicknesses of the inner layers of the macula in both eyes of patients with unilateral primary open-angle glaucoma (POAG) and compare them with normal control eyes.

This prospective, cross-sectional pilot study enrolled patients with unilateral POAG, who had visual field defect in only 1 eye, and controls with a normal eye examination. Horizontal and vertical B-scan images centered on the fovea were obtained using spectral domain optical coherence. Semiautomatic delineation and segmentation of the inner layers of the retina were performed to evaluate macular retinal nerve fiber layer (mRNFL), ganglion cell complex (GCC) and ganglion cell-inner plexiform layer (GC-IPL) thicknesses. Mean, superior, inferior, nasal, and temporal inner macular layer thicknesses were compared between affected eyes, fellow eyes without visual field defect, and control eyes.

Nineteen patients with unilateral POAG and 14 normal control eyes were enrolled. In the affected POAG eyes, thinning of the mRNFL, GCC, and GC-IPL layers on horizontal and vertical scans were significant when compared with controls (P<0.05), particularly on vertical scans (P<0.001). The mean regional macular GCC and GC-IPL were most severely thinned in the inferior and temporal perifoveal regions. The unaffected eye of patients with unilateral POAG showed significant thinning of the mRNFL only in the vertical scan when compared with normal controls (P<0.05).

Spectral domain optical coherence tomography detected significant thinning of the mRNFL, GCC, and GC-IPL in the affected eyes of patients with unilateral POAG. Fellow eyes showed early structural changes only in the vertical mRNFL scans when compared with normal controls.