Analysis of twisted internal carotid arteries in carotid endarterectomy

Background The twisted carotid artery is a variant, in which the internal carotid artery (ICA) courses medially to the external carotid artery. Due to the sparse descriptions in the literature, we, here, report our experience with cases of carotid endarterectomy (CEA) for twisted carotid artery and its clinical features. Methods Fifty-seven consecutive CEA-treated patients were evaluated, and the twist angle was measured on the source images of axial slices of computed tomography angiography (CTA). Results Eight male patients (14.2%) demonstrated a twisted right ICA (mean age, 77.0 ± 2.6 years; and mean stenosis, 66.9% ± 19.9%). The mean twist angle was 30.1° ± 17.9°, while the normal ICA is angled at -23.0° ± 12.3°. No statistical differences in the distribution of coexisting diseases were found between the normal and twisted ICA cases. CEA was successfully performed with the correction of the carotid position in all cases; however, significant position correction was not observed in the postoperative evaluation. Right-side dominancy (P = 0.045) and prolonged clamping time (P = 0.053) were observed in the twisted cases. Conclusion Twisted ICA was preferentially found in the right ICA and men. CEA of the twisted ICA was safely performed with appropriate head rotation and wider longitudinal skin incision than usual without a significant increase in the operative time. CTA is useful for preoperative evaluation. This specific variation should be considered by the neurosurgeon involved in the evaluation and treatment of carotid stenoses.