Evaluation of macular and optic nerve head changes by optical coherence tomography angiography in glaucomatous eyes

Abstract

Background Optical coherence tomography angiography (OCTA) is introduced as a safe, noninvasive, and dye-free technology that provides an assessment of both large vessels and microvasculature of the retina and some parts of the choriocapillaris. Measuring vessel densities using OCTA at both the macula and optic nerve head (ONH) in glaucomatous eyes and comparing them with those of normal eyes will give us an idea about the effect of glaucoma on vessel densities and the role of OCTA in controlling and monitoring glaucoma progression, which remains despite the various medical and surgical treatment options, the second most common reason of blindness worldwide. Aims The current study aimed to assess vessel densities in glaucomatous patients at both the macula and ONH and compare them with vessel densities of normal participants and to assess if OCTA can be useful in the diagnosis and monitoring of the disease. Settings and design Case–control study. Patients and methods The study enrolled 60 patients who were divided into two groups. Group 1 included 30 patients with any type of glaucoma and group 2 included 30 normal participants. OCTA was performed on all of them to assess the macular and ONH vessel densities. Results Glaucomatous patients showed decreased vessel density at the macula and the ONH. The vessel densities at the foveal and all quadrants of parafoveal regions of the macula were decreased when compared with vessel densities of normal participants. Vessel densities at all quadrants of the peripapillary region also decreased when compared with those of normal participants with a strong positive correlation between average peripapillary vessel density and average peripapillary retinal nerve fiber layer thickness. Conclusions Both macular vessel density and ONH vessel density are affected in glaucoma and that may play a role in the diagnosis and follow-up of the disease.