Peripapillary Perfused Capillary Density in Acute Angle-Closure Glaucoma: An Optical Coherence Tomography Angiography Study

Purpose: To compare peripapillary perfused capillary density (PCD) on optical coherence tomography angiography among resolved acute angleclosure (AAC), primary open-angle glaucoma (POAG), and control eyes. Design: Prospective, cross-sectional, observational study. Methods: All patients with resolved AAC, or POAG of varying severity and controls were enrolled. We obtained 4.5 x 4.5 mm(2) optical coherence tomography angiography images of the optic nerve head. PCD was analyzed using customized software with major vessel removal. Continuous variables were assessed using the analysis of variance and Bonierroni correction test. A marginal model of generalized estimating equations was used to adjust for confounding factors and interocular correlation. Results: The study included 44 eyes with resolved AAC (mean duration of elevated intraocular pressure, 8.1 +/- 10.9 days), 69 eyes with POAG, and 49 control eyes. PCD showed a similar decrease between AAC and POAG eyes (P > 0.99). After adjusting for age and sex, the mean difference in global PCD between each of the POAG stage groups and the AAC group was the highest in the severe POAG group (-3.43; 95% confidence interval [CI], -11.38 to 2.52; P = 0.211), followed by the mild POAG (0.68; 95% CI, -3.26 to 4.62; P = 0.735) and moderate POAG (0.20; 95% CI, -5.21 to 5.61; P= 0.942) groups. The duration of increased intraocular pressure did not affect PCD (P= 0.258 and 0.168 for global and annular PCDs, respectively). Conclusions: The degree of microvascular attenuation in AAC eyes was not different from that in POAG eyes.