Ganglion cell analysis versus retinal nerve fiber layer thickness in glaucoma diagnosis

Abstract

Background Glaucoma is a progressive optic neuropathy, which can result in irreversible blindness. The main pathologic change in glaucoma is retinal ganglion cell loss. The macula has the greatest density of retinal ganglion cells (∼50%). The advent of spectral domain-optical coherence tomography (OCT) technology has allowed advanced macular imaging protocols to play an important role in the diagnosis and monitoring of glaucoma. The ganglion cell analysis is obtained by the Cirrus HD-OCT system segments and measures the thickness of the ganglion cell‑inner plexiform layer, thereby potentially increasing its diagnostic accuracy compared with conventional peripapillary retinal nerve fiber layer (RNFL) thickness measurement. Patients and methods The study was done on 40 eyes of 40 patients, and patients were divided into two groups: Group 1 included 20 adult patients more than 18 years who were diagnosed with primary open-angle glaucoma. Group 2 included 20 normal controls. One eye of each individual was prospectively enrolled. The OCT was done using 3D-OCT 2000 (Topcon) to evaluate the following: RNFL parameters (average total thickness, superior average thickness, and inferior average thickness) and ganglion cell complex (GCC) parameters (total average thickness, superior average thickness, and inferior average thickness). Result There was a positive statistically significant correlation of high probability between the two groups regarding RNFL thickness (P Conclusion Early diagnosis of glaucoma and early initiation of treatment is extremely important, as further vision loss can be stopped or slowed down. RNFL and GCC measurement with spectral domain-OCT could provide important information for detection and evaluation of glaucoma. There is strong positive correlation between the RNFL thickness and the GCC thickness in the glaucomatous patients.