Relevance of Primitive Carotidobasilar Anastomosis for Internal Carotid Artery Stenosis

Primitive carotido-basilar anastomoses (PCA) are persistent fetal vessels. The aim of the study was to compare the clinical characteristics of patients operated on for internal carotid artery (ICA) stenosis with or without PCA in order to evaluate the impact of PCA on the treatment. Material and methods. Consecutive patients operated on for ICA stenosis at our university hospital were included. Surgical treatment consisted in carotid endarterectomy (CEA) with patch plastic. Results. Of the 380 CEA performed between 2006 and 2012, PCA were found in six patients (1.6%). All patients with PCA were symptomatic vs. 54% of patients without PCA (p=0.035). Significantly less posterior collateral flow was present in patients with PCA (33%) compared to those without PCA (85%, p=0.01). Only two of the six patients with PCA were diagnosed prior to surgery, none was ligated intraoperatively. PCA was not associated with stroke and restenosis at long-term follow up. Conclusions. PCA are rarely diagnosed prior to surgery in patients with ICA stenosis and need not to be ligated during CEA