Risk Factors of Cerebellar Microembolic Infarctions Following Carotid Artery Stenting.

Abstract This study analyzes the incidence of microembolic infarctions (MIs) in the cerebellum following carotid artery stenting (CAS) to determine the risk factors. From 2012 to 2019, 162 CASs in 155 patients were performed at our hospital. Fifty-seven (35.7%) patients demonstrating new MIs on diffusion-weighted imaging after CAS were enrolled. Patients were assigned to either the cerebellar group (n = 14, 8.8%) if their MIs were in the cerebellum and/or cerebrum, or the cerebral group (n = 43, 26.9%) if their MIs were only in the cerebrum. Patient characteristics, anatomical features, and clinical data were retrospectively compared between the two groups. Advanced age, right-sided carotid stenosis, severe calcification of aortic arch and brachiocephalic trunk, and vertebral artery narrowing with intraprocedural hemodynamic depression (IHD) significantly increased the development of cerebellar MIs. On multivariate analysis, advanced age, right-sided carotid stenosis, and vertebral artery narrowing with IHD were independent predictors of developing new cerebellar MIs. Cerebellar MIs after CAS were not uncommon. Catheter maneuvering in the aortic arch or the brachiocephalic trunk could be the main cause of thromboemboli in cerebellar MIs. Careful attention should be paid to catheter maneuvering, especially in older patients with right-sided carotid lesions. Additionally, cerebellar hypoperfusion due to vertebral artery narrowing with IHD might reduce washout of debris, a cause of cerebellar MIs.