Figure 1

Measurements of parapapillary choroidal vessel density (VD) and intradisc VD and confirmation of the presence of choroidal microvascular dropout (CMvD), and optic disc microvascular dropout (MvD) in a primary open-angle glaucoma (POAG) eye with CMvD using swept-source optical coherence tomography angiography (SS-OCTA). (A) The blue ellipse line shows the optic nerve head (ONH) margin. The yellow outline indicates the β-parapapillary atrophy (β-PPA) margins, excluding large retinal vessels, which are applied to the SS-OCTA choroidal layer en-face image. The selected area of interest, excluding large retinal vessels, within the β-PPA was converted to a region of interest (ROI), (B) then applied to the 8-bit binary slab of an SS-OCTA choroidal layer en-face image. (C) The ROI within the ONH, excluding large retinal vessels, was manually demarcated on a whole-signal mode ONH en-face image. (D) These areas of interest were used to measure the intradisc VD (orange outline) using the ImageJ software. (E) The presence of CMvD (green arrow) and optic disc MvD (yellow arrow) was detected (F) using a horizontal B-scan that showed loss of microvasculature signal in the prelaminar tissue and anterior portion of lamina cribrosa.