Decreased Choriocapillaris Vessel Density in the Ipsilateral Eye after Carotid Artery Revascularization Detected by Widefield Swept-Source OCT Angiography

Objective: To investigate the short-term blood flow changes and image features of the retina and choroid in patients who underwent carotid artery revascularization (CAR) for severe carotid artery stenosis using widefield Participants: This prospective study included 112 eyes (56 eyes on the ipsilateral side and 56 eyes on the contralateral side) of 56 participants with severe carotid artery stenosis. Methods: Participants were examined using widefield swept-source OCTA covering an area of 16 x 16 mm centered on the fovea before and after CAR. Retinal parameters including central macular thickness, vessel density of the retinal superficial vascular complex (VDRSVC), vessel density of the retinal deep vascular complex, and vessel density of the retina (VDR) and choroidal parameters, including central choroidal thickness (CCT), vessel density of the choriocapillaris (VDCC), vessel density of the medium and large choroidal vessels, choroidal vessel volume ratio (CVV/a), and 3-dimensional choroidal vascularity index (3D-CVI) were measured. Besides, preoperative and postoperative OCTA images were screened and compared. Main Outcome Measures: Retinal and choroidal parameters obtained from swept-source OCTA. Results: In the ipsilateral eye (56 eyes), an increase in VDRSVC, VDR, CVV/a, CCT, and 3D-CVI and a decrease in VDCC was found after CAR. Thirteen patients were identified with postoperative ipsilateral choriocapillaris flow voids (PICCFVs) with OCTA images, and the presence of PICCFVs was associated with greater postoperative VDCC decrease. In the contralateral eye (56 eyes), we found an increase in VDRSVC, vessel density of the retinal deep vascular complex, and VDR, whereas no difference in choroidal parameters after CAR and no findings of PICCFVs were found. Conclusions: The findings of this study suggest that ocular microvascular perfusion is improved after CAR in the ipsilateral eye and the contralateral eye within a wide field of the fundus. The VDCC is decreased in the ipsilateral eye, which may indicate infarctions of choriocapillaris or ischemia-reperfusion injury of the choriocapillaris after CAR. Financial Disclosure(s): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article. Ophthalmology Science 2025;5:100654 (c) 2024 by the American Academy of Ophthalmology. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/