Optical Coherence Tomography Angiography of Retinal Artery Occlusion

Purpose: To evaluate retinal vascular layers in Retinal Artery Occlusion (RAO) imaged by Optical Coherence Tomographic Angiography (OCTA). Methods: A series of 4 eyes with acute RAO were enrolled in an observational case series study. Acute RAO was defined as retinal whitening and ischemia, and on OCT B-scan, inner retinal thickening with disruption of the retinal layers. OCTA cube scans (3x3 mm) were acquired using the RTVue-XR Avanti AngioVue, with Split- Spectrum Amplitude-Decorrelation Angiography algorithm, and motion correction technology. Images of the superficial and deep capillary plexus were analyzed and compared with structural Optical Coherence Tomography (OCT). Results: OCTA findings were as decreased vascular perfusion in both the superficial and deep capillary plexuses corresponding to the areas of the inner retinal changes on OCT B-scan and fundus changes. Only large vessels were imaged. No vascular flow was observed in area nourished by the microvascular bed.Conclusion: OCTA is a useful diagnostic tool used to demonstrate the features necessary to diagnose RAO. Compared to FA, OCTA is fast, noninvasive, and can provide improved visualization of microvascular details.