Simple classification of carotid bifurcation: is it possible to predict twisted carotid artery during carotid endarterectomy?

BACKGROUND

The internal carotid artery (ICA) usually runs posterolaterally to the external carotid artery (ECA), but occasionally we encounter the twisted carotid bifurcation, a variant in which the ICA courses medially to the ECA during carotid endarterectomy (CEA). Prediction of this anomaly in the preoperative evaluation is mandatory, although descriptions in the literature are limited. We reviewed the clinical features of patients who underwent CEA and analyzed preoperative cerebral angiography, especially the anteroposterior (AP) view to determine whether it could be a predictive modality.

METHODS

In 58 consecutive CEA cases, we simply classified them into three groups; type 1 (the ICA runs laterally and the ECA runs medially), type 2 (the ICA and ECA run to overlap each other), and type 3 (the ICA runs medially and the ECA runs laterally), based on the findings of AP view of cerebral angiography. We compared the clinical features and intraoperative findings of these groups.

RESULTS

Of 58 cases, types 1-3 were 24, 30, and four cases, respectively. Twisted carotid bifurcations were recognized in seven cases (12.4 %), including three cases in type 2 and four in type 3, and all twisted cases were found on the right side. Twisted carotids and right-sided lesion were significantly frequent in type 3, but no statistical differences of coexisting diseases were recognized among the three groups. CEAs of twisted carotid bifurcations were performed successfully with correction of the carotid position in three and as it was in four cases.

CONCLUSIONS

Twisted carotid bifurcations were observed during operation in 10 % in type 2 and 100 % in type 3. CEA of twisted carotid bifurcations can be performed safely with or without correction of the carotid position. AP view of cerebral angiography could be useful for preoperative evaluation.