DETECTION AND CHARACTERISTICS OF UNRUPTURED RETINAL ARTERIAL MACROANEURYSMS.

PURPOSE: To determine the presence of unruptured retinal arterial macroaneurysms (RAMs) and to examine the characteristics of the detected lesions. METHODS: This retrospective observational study included the affected and contralateral eyes of 50 patients (100 eyes) with symptomatic, unilateral, ruptured RAMs who visited the Department of Ophthalmology at the Kyoto University Hospital (April 2014-April 2020) and were followed up for at least 6 months after the onset. The presence and characteristics of unruptured RAMs were examined by reviewing the findings of color fundus photography and infrared scanning laser ophthalmoscopy performed before the onset or during the follow-up period. RESULTS: Unruptured RAMs were detected in six of the 50 patients. Some patients had bilateral or multiple unruptured RAMs, and a total of 12 unruptured RAMs were detected in eight eyes of the six patients. Among the detected lesions, eight exhibited a longitudinal increase in their diameter during the follow-up period, whereas six exhibited ruptures. CONCLUSION: Unruptured RAM is not an uncommon retinal vascular abnormality and can enlarge and progress to ruptured RAM.

Three-dimensional locations of ruptured retinal arterial macroaneurysms and their associations with the visual prognosis.

The aim of this retrospective, observational study was to examine the intraretinal locations of ruptured retinal arterial macroaneurysms (RMAs) and investigate the associations with the visual prognosis. Fifty patients (50 eyes) with untreated RMA rupture who visited the Department of Ophthalmology at Kyoto University Hospital (April 2014-July 2019) were included. The intraretinal position of the ruptured RMAs relative to the affected retinal artery was examined using optical coherence tomography (OCT) and color fundus photography (CFP). The relative RMA positions were anterior to (anterior type, 44%), at the same level as (lateral type, 20%), or posterior to (posterior type, 34%) the affected artery. At the initial visit, the posterior type showed greater subretinal hemorrhage thickness than did the lateral and anterior types (P = 0.016 and 0.006, respectively), and poorer visual acuity (VA) than did the anterior type (P = 0.005). At the final visit, the length of the foveal ellipsoid zone band defect was longer (P = 0.005) and VA was poorer (P < 0.001) for the posterior type than for the anterior type. The intraretinal positions of ruptured RMAs vary, affect the thickness of foveal subretinal hemorrhage and predict future damage to the foveal photoreceptors. The visual prognosis may be poor for posteriorly ruptured RMAs.

Peripheral Chorioretinal Imaging Through a Front Prism on Optical Coherence Tomography Angiography.

Purpose: To evaluate the clinical feasibility of peripheral chorioretinal imaging through a front prism on swept-source optical coherence tomography angiography (SS-OCTA). Methods: We prospectively obtained en face OCTA images using SS-OCTA in 10 eyes of 10 healthy volunteers. For the peripheral chorioretinal imaging, the scanning laser passed and refracted through a 45°-90°-45° right-angle prism. We evaluated the qualitative and quantitative characteristics of chorioretinal vessels in the periphery. Results: Using peripheral chorioretinal imaging through a prism, the retinal vasculature was delineated to the equator on the OCTA images, and varices of the vortex vein ampullae were observed on choroidal OCT images. The 3 × 3-mm images revealed three-dimensional morphologies unique to the peripheral vasculature, such as the gap between retinal arterioles and venules in the superficial capillary plexus (SCP) and elliptical and greater lobules in the choriocapillaris layer. Compared with OCTA images obtained without the prism, those obtained through the prism demonstrated an approximately 1.24-fold increase in the lengths in the base apex direction, whereas the lengths in the perpendicular direction showed concordance. The peripheral vessel density (VD) in the inferior quadrant was lower than those in the other quadrants on the SCP and deep capillary plexus, whereas on the SCP images of the macula the lowest VD was observed in the temporal subfield. Conclusions: Peripheral chorioretinal imaging allowed us to generate ultra-widefield panoramic OCTA images and demonstrated morphologic characteristics unique to peripheral chorioretinal vessels. Translational Relevance: OCTA imaging through a front prism can be a technique for acquiring chorioretinal vasculature images in the periphery.