Material and Methods: Sixty eyes of 30 primary open angle glaucoma patients who were treated in the glaucoma unit of our clinic and 32 eyes of 16 controls were enrolled. Peripapillary retinal nerve fiber layer (RNFL) thickness was measured in all patients with a spectral domain optic coherence tomography (SD-OCT), (Heidelberg Spectralis HRA/OCT). The scan was repeated after the center of the 3,4 mm circular OCT section was focused on central fovea. Ganglion cell complex thickness was measured by changing the outer reference line of RNFL to the outer border of inner plexiform layer manually. The results of glaucomatous eyes were compared with controls. Mean deviation (MD) values of the visual field was also recorded with standard automated perimetry (Humphrey Field Analyzer II, Model 750) and SITA-standard test. T-test and Pearson correlation test were used in statistical analysis of dependent and independent samples.

Results: Mean age of all enrolled subjects was 55.4 (±8.2; 38-75) and women to men ration was 31/15. Mean peripapillary RNFL thickness was measured 105.9±17.5 μm and 115.9±9.4 μm in glaucoma and control group respectively. The thinner RNFL thickness in glaucomatous eyes was statistically significant (p=0.003). Mean GCC thickness was recorded 85.6±19.6 μm and 98.1±9.5 μm in glaucomatous eyes and controls, respectively. GCC was also significantly thinner in the glaucoma group (p<0.001). There was high positive correlation between GCC and RNFL thickness in glaucomatous eyes (r2=0.806). Also there was a siginificant correlation between MD and perifoveal GCC as well as beween MD and peripapillary RNFL (r2=0.528 and r2=0.490 respectively).

Conclusions: Perifoveal ganglion cell complex thickness is thinner in glaucoma compared with normal eyes. This can be a parameter in early diagnosis and management of glaucoma. Keywords : Ganglion cell complex, glaucoma, optic coherence tomography, retinal nerve fiber layer, visual field