Differences in Relationship Between Macular Inner Retinal Layer Thickness and Retinal Sensitivity in Eyes With Early and Progressed Glaucoma

PURPOSE. To determine if the relationship between retinal sensitivity and macular inner retinal layer thickness differs between primary open-angle glaucoma (POAG) with mild and advanced central visual field (VF) damage. METHODS. One eye of 153 POAG patients was included. Using spectral-domain optical coherence tomography, we measured the average thickness of the macular ganglion cell-inner plexiform layers (GCIPLT) and the macular nerve fiber layer/GCIPL (ganglion cell complex [GCCT]) in a 0.9-mm-diameter ganglion cell displacement-adjusted circular area corresponding to the four central test points of the Humphrey Perimeter 24-2 program and correlated the results with the average retinal sensitivity (1/Lambert) at the corresponding test points, with adjustment for other confounding factors. RESULTS. Ninety-three eyes had mild central and 60 eyes advanced central VF damage with an average total deviation (TD) of the four test points of greater than or equal to 4 decibels (dB) (mild group) and less than -4 dB (more severe group), respectively; the average mean deviations were -3.0 and -9.8 dB, respectively. In the mild group, the GCCT and GCIPLT were correlated significantly and positively with the average retinal sensitivity with partial regression coefficient of 0.007 and 0.005, respectively, and in the more severe group with partial regression coefficient of 0.019 = 0.007 + 0.012 (P = 0.007) and 0.010 = 0.005 + 0.005 (P = 0.078), respectively. The axial length and disc size were correlated with GCIPLT with marginal significance (P = 0.052 and P = 0.042). CONCLUSIONS. The relationship between the macular GCC and GCIPL thickness and retinal sensitivity at the corresponding retinal areas differed between POAG with mild and advanced central VF damage.