Comparison of Vascular Density and Structural Patterns Between Primary Open Angle Glaucoma and Primary Angle Closure Glaucoma

Purpose: To compare the pattern of vascular density and structural damage in primary open angle glaucoma (POAG) with primary angle closure glaucoma (PACG) using optical coherence tomography (OCT) and OCT angiography (OCTA) in the optic nerve head, circumpapillary, and macular regions, respectively. Materials and Methods: One hundred thirty-one eyes of 82 patients (53 eyes with PACG and 78 eyes with POAG) were enrolled in this study. The patients underwent complete ophthalmic examination, Bruch membrane opening minimum rim width, circumpapillay retinal nerve fiber layer (cpRNFL), and macular ganglion cell complex (GCC) measurements and vascular density determination of the peripapillary and macular area with OCT and OCTA. A linear mixed model was used for the statistical analysis. Results: There was no significant difference between the 2 groups in terms of age (P=0.94) and visual field mean deviation (P=0.78). Female-to-male ratio was higher in PACG patients than the POAG group (P=0.02), and AL was shorter in PACG eyes (P<0.001). cpRNFL and GCC were not different between the 2 groups (all P values>0.05, except for nasal segment cpRNFL). Vessel densities in the peripapillary and macular areas were comparable between the 2 groups (all P values>0.05). Although Bruch membrane opening minimum rim width was thicker in PACG eyes on univariate analysis, the multivariable analysis showed no significant difference between the 2 groups (P>0.05). Conclusions: PACG and POAG eyes with similar visual field damages have comparable structural damage patterns in the peripapillary and inner macular thickness and vessel density measurements.