Comparison of changes of macular ganglion cell-inner plexiform layer defect between stable group and progression group in primary open-angle glaucoma

Purpose To compare the changes in macular ganglion cell-inner plexiform layer (GCIPL) defect between stable and progression primary open-angle glaucoma (POAG) groups. Study design Retrospective observational study. Methods A total of 100 POAG eyes with localized retinal nerve fiber layer (RNFL) defect and corresponding macular GCIPL defect were selected for this study. Glaucoma progression was defined by either structural or functional deterioration. The number of abnormal superpixels on macular GCIPL deviation maps was calculated using a customized MATLAB program. GCIPL defect change was evaluated in two aspects: increased angular width and increased area. The defect patterns were categorized and compared between the stable and progression groups. Results The increase rate of angular width of GCIPL defect was higher in the progression group than in the stable group (P = 0.029). In respect to the area of GCIPL defect, there was no statistically significant differences between the groups (P = 0.227). Twenty-seven (27) of 100 (27.0%) eyes showed increased angular width of GCIPL defect. It was more frequent in the progression group than in the stable group (P = 0.043). Seventeen (17) of 27 (63.0%) eyes showed the away from the horizontal temporal raphe type progression and it was the most common change pattern of angular width of GCIPL defect. Conclusions Increased angular width of GCIPL defect was the more prominent feature of change, and was more frequent in the progression group than in the stable group. Among the types of GCIPL defect classified, the away from the horizontal temporal raphe type was the most common.