The Pattern of Retinal Nerve Fiber Layer and Macular Ganglion Cell-Inner Plexiform Layer Thickness Changes in Glaucoma

BACKGROUND/AIMS: To investigate the patterns of retinal ganglion cell damage at different stages of glaucoma, using the circumpapillary retinal nerve fiber layer (RNFL) and macula ganglion cell-inner plexiform layer (GCIPL) thicknesses. METHODS: In 296 eyes of 296 glaucoma patients and 55 eyes of 55 healthy controls, the correlations of mean deviation (MD) with the superior and inferior quadrant RNFL/GCIPL thickness (defined as the average of three superior and inferior sectors, resp.) were analyzed. RESULTS: In early to moderate glaucoma, most of the RNFL/GCIPL thicknesses had significant positive correlations with the MD. In advanced glaucoma, the superior GCIPL thickness showed the highest correlation with MD (r = 0.495), followed by the superior RNFL (r = 0.452) (all; P < 0.05). The correlation coefficient of the inferior RNFL thickness with MD (r < 0.471) was significantly stronger in early to moderate glaucoma compared to that in advanced glaucoma (r = 0.192; P < 0.001). In contrast, the correlations of the superior GCIPL thickness with MD (r = 0.452) in advanced glaucoma was significantly stronger compared to that in early to moderate glaucoma (r = 0.159; P < 0.001). CONCLUSIONS: The most preserved region in advanced glaucoma appears to be the superior macular GCIPL, whereas the most vulnerable region for initial glaucoma is the inferior RNFL around the optic disc.