Assessment of Retinal Perfusion and Vascular Density in Obstructive Sleep Apnea Syndrome With Swept-Source Optical Coherence Tomography Angiography.

Numerous ocular conditions, including non-arteritic anterior ischemic optic neuropathy, glaucoma, retinal venous occlusion, and diabetic retinopathy, are associated with obstructive sleep apnea syndrome (OSAS). This study aimed to assess changes in the vascular density and perfusion area across various retinal layers in patients diagnosed with OSAS using swept-source optical coherence tomography angiography (OCTA) with a 12 × 12 mm scan mode. A total of 80 participants with OSAS underwent overnight polysomnography to assess the severity of sleep apnea, followed by OCTA measurements to collect data on vascular density and perfusion area across each retinal layer and segmentation. Participants were divided into three groups: 28 in Group 1 (no OSAS/mild OSAS), 22 in Group 2 (moderate OSAS), and 30 in Group 3 (severe OSAS). Perfusion areas differed significantly among the three groups in the retina, inner retina, choroid, nerve fibres, superficial vascular plexus (SVP), and intermediate capillary plexus (ICP) layers. In addition, vascular densities also showed significant differences in the inner retina, nerve fibres, and ICP layers. Notably, apnea-hypopnoea index scores correlated significantly with perfusion areas in the retina, SVP, and ICP, as well as with vascular densities in the nerve fibre layer, SVP, and ICP. Significant changes in vascular density and perfusion area were observed in patients with moderate to severe OSAS, suggesting that OCTA may be a valuable non-invasive method to assess changes in blood flow that are associated with sleep apnea.