Optical Coherence Tomography Angiography Evaluation of Retinal Microvasculature Before and After Carotid Angioplasty and Stenting

The aim of the study was to evaluate the influence of carotid angioplasty and stenting (CAS) on retinal microvasculature using optical coherence tomography angiography (OCTA) in patients with severe carotid stenosis. 20 patients with severe carotid stenosis underwent comprehensive ophthalmic examinations and OCTA before and one month after CAS. Automated algorithms were used to quantify vessel density in the macular superficial vascular complex (SVC), deep vascular complex (DVC), and radial peripapillary capillary (RPC) around the optic disc. Eyes on the operated side constituted the ipsilateral eye group, and the other eye constituted the fellow eye group. In the ipsilateral eye group, the vessel density in the DVC increased significantly after stent implantation (P = 0.010), but the vessel density change in the SVC was not statistically different (P = 0.999). In the fellow eye group, the vessel density in the SVC (P = 0.028) and DVC (P = 0.034) were significantly increased after stent implantation. The vessel density in the RPC did not significantly change in the ipsilateral (P = 0.363) or fellow (P = 0.878) eye groups. This study shows that unilateral CAS for severe carotid stenosis increases macular vessel densities in both eyes.