Anatomical features and clinical significance of the ascending pharyngeal artery in carotid endarterectomy

This study aimed to elucidate the anatomical characteristics of the ascending pharyngeal artery (APhA) using three-dimensional rotational angiography (3D-RA) and its role in preventing complications during carotid endarterectomy (CEA). Data from 279 primary CEAs (259 patients; median age, 73 years; male/female ratio, 6.2:1) conducted between 2006 and 2022 at a single center were retrospectively analyzed. The APhA anatomy was evaluated using carotid 3D-RA. The APhA was identified on 3D-RA in 277 of 279 carotid arteries (99.3%), with 98.6% showing a single APhA and 1.4% duplication. Among single APhAs, 60.1% arose from the external carotid artery (ECA), 34.8% from the occipital artery, 3.3% from the internal carotid artery, and 1.5% from the carotid bifurcation. Of the 170 APhAs directly arising from the ECA, 64.1% originated from the medial wall and 35.9% from the posterior wall. A higher carotid bifurcation level significantly correlated with a shorter distance between the APhA origin and carotid bifurcation (Spearman’s rho = − 0.583; p < 0.001). During CEA, APhA manipulation with cross-clamping was required in 15.8% (44/279) of cases, and no unexpected back-bleeding occurred. The incidence of cranial nerve injury (CNI) was 1.4% (4/279), with a trend toward higher risk when the APhA was manipulated (odds ratio, 5.70; p = 0.086). The APhA typically originates medially or posteriorly from the carotid artery. In standard antero-lateral CEA approaches, this places the APhA on the obscured backside of the artery, emphasizing the importance of preoperative identification and intraoperative management to prevent back-bleeding and CNI.