Purpose: To investigate whether the relationship between circumpapillary vascular density (cpVD) and visual field (VF) mean sensitivity (MS) differs between primary open-angle (POAG) and angle-closure glaucoma (PACG).
Methods: The cpVD and retinal nerve fiber layer thickness (RNFLT) were obtained using optical coherence tomography angiography (OCTA, AngioVue/RTVue-XR) in 146 eyes from 146 subjects (age- and VF mean deviation-matched 86 POAG and 60 PACG). Global and regional relationships (superotemporal [ST], superonasal [SN], nasoupper [NU], nasolower [NL], inferonasal [IN], inferotemoporal [IT], temporolower [TL], and temporoupper [TU] sectors) were estimated between cpVD and VF MS using multiple linear regression models controlling for the confounding variables in two disease categories. Uni- and multivariate linear regression models were built using cpVD as the dependent variable and covariates (age, intraocular pressure [IOP], axial length, signal strength index, and RNFLT) as independent variables.
Results: In PACG eyes, the cpVD was associated with the corresponding VF MS in five sectors (semipartial correlation coefficient [sr]: 0.144-0.567, P < 0.05): IN, IT, ST, TL, and SN, while the RNFLT showed association in four sectors (sr: 0.047-0.544, P < 0.05). In POAG eyes, the cpVD of all sectors was associated with the corresponding VF MS (sr: 0.246-0.574, P < 0.05). Greater IOP and lower RNFLT were independently associated with reduction of cpVD in the PACG group (P = 0.002, P < 0.001). In the meantime, only lower RNFLT was associated with reduction of cpVD in the POAG group (P < 0.001).
Conclusions: POAG and PACG eyes differed in vascular-function relationship determined by OCTA and VF MS.