Persistent Proatlantal Intersegmental Artery(PPIA):Are Consideration Based On MSCTA

Abstract

Background Persistent proatlantal intersegmental artery (PPIA) is a rare permanent carotid-basilar anastomosis. Multi-slice spiral CT Angiography (MSCTA) has become the primary non-invasive imaging technique for evaluating cephalic and cervical vascular anatomy. Purpose To investigate the MSCTA imaging characteristics of PPIA and its clinical values, and then to provide a new classification method based on posterior circulation blood supply. Material and Methods The imaging and clinical data of 11 patients with PPIA diagnosed by MSCTA through combined head and neck scanning were analyzed retrospectively. Results The incidence of PPIA was 0.01%. Classification according to the starting position of PPIA revealed 2 cases (18.2%) of type I and 9 cases (81.8%) of type II. When classified according to the blood supply of posterior circulation, type 1 of PPIA had 4 cases (36.4%), type 2 had 4 cases (36.4%), type 3 had 1 case (9.1%), and type 4 had 2 cases (18.2%). Among the 11 PPIA patients, there were 11 cases of ipsilateral vertebral artery absence, 3 cases of contralateral vertebral artery dysplasia, 1 case of contralateral vertebral artery absence, 2 cases of persistent artery dysplasia, and 2 cases of basilar artery dysplasia. Additionally, there were 2 patients with aneurysms, 1 patient with cerebral infarction, and 1 patient with Pulmonary Arteriovenous Fistula (PAVF). Conclusion The new classification of PPIA is more conducive to evaluating posterior circulation blood supply and providing a more comprehensive imaging evaluation for interventional and surgical procedures. MSCTA can accurately diagnose PPIA and reduce the rate of missed diagnoses of other vascular diseases.