Topographic Correlation Between Juxtapapillary Choroidal Thickness and Microstructure of Parapapillary Atrophy

Purpose: To investigate the topographic relationship between the juxtapapillary choroidal thickness (JPCT) and the microstructure of parapapillary atrophy (PPA) in primary open-angle glaucoma (POAG). Design: Cross-sectional observational study. Participants: A total of 126 eyes (76 POAG eyes and 50 healthy control eyes) of 126 subjects with beta-zone PPA. Methods: Optic nerve heads were imaged using spectral-domain optical coherence tomography (OCT) to measure the JPCT. On the basis of the extent of Bruch's membrane (BM) within the beta-zone PPA, the beta-zone PPA was divided into PPA with intact BM (PPA(+BM)) and PPA devoid of BM (PPA(-BM)). The width of each type of PPA, together with the JPCT, was measured at 12 meridians on 6 radial B-scan images. Main Outcome Measures: Topographic correlation between the width of PPA(+BM) and PPA(-BM) and the JPCT and factors associated with the JPCT. Results: The JPCT was significantly smaller in the POAG group than in the healthy control group in the inferotemporal region (6, 7, 8, and 9 o'clock; all P <= 0.0002). The PPA(+BM) width was larger in the POAG group in the inferotemporal region (6, 7, 8, and 9 o'clock; P <= 0.004), whereas the PPA(-BM) width did not show significant differences between groups in any of the locations. Regression analysis revealed a significant influence of older age (P = 0.002) in the healthy control group and a significant influence of older age (P < 0.001) and a larger PPA(+BM) width (P = 0.006) on the smaller JPCT in the POAG group. Conclusions: The JPCT was topographically correlated with the PPA(+BM) width but not with the PPA(-BM) width. Juxtapapillary choroidal atrophy and the formation of PPA(+BM), but not the formation of PPA(-BM), may share a common pathogenic mechanism in glaucomatous optic nerve damage. (C) 2016 by the American Academy of Ophthalmology.