Assessment of hemodynamic changes of persistent carotid-vertebrobasilar anastomoses by ultrasonography / 中国脑血管病杂志

ABSTRACT

Objective: Evaluate the hemodynamic characteristics of primitive carotid-vertebrobasilar anastomoses(PCVBA) by the combination of carotid duplex ultrasonography(CDU) and transcranial colorcoded sonography(TCCS). Methods: From July 2016 to July 2018, 14 patients combined screened by CDU and TCCS and confirmed by computed tomography angiography (CTA) in the Department of Neurology and Neurosurgery, Xuanwu Hospital were retrospectively and consecutively enrolled. The hemodynamic parameters, including peak systolic velocity (PSV) and resistance index (RI), were acquired in vertebral artery(VA).basilar artery(BA) and posterior cerebral artery. The vessel diameter of the extracranial VA was measured as well. Results: (1) Of 14 cases, 12 patients(12/14) represented dizziness, and 5 patients had posterior ischemic stroke, from whom there were 4 cases associated with ipsilateral internal carotid artery stenosis ≥50%. (2) Persistent trigeminal artery(PTA) was confirmed in 6 cases with high RI in bilateral extracranial VA. The velocity of distal BA was decreased when compressing the ipsilateral common carotid artery. (3)There were 5 persistent hypoglossal artery(PHA) and 3 proatlantal intersegmental artery (PIA), 1 case with type I PIA and 2 cases with type Jl PIA. CDU showed PHA and type I PIA arising from the extracranial internal carotid artery, and type II arising from the external carotid artery. All patients had ipsilateral VA absent, which has a tiny-lumen with low PSV and high RI or without flow, but TCCS showed normal blood flow in ipsilateral intracranial VA and BA, which was significantly decreased when compressing the ipsilateral common carotid artery. The contralateral VA were absent in 4 patients, and were hypoplastic in the other 4 patients. Conclusions: The abnormal hemodynamic changes of PCVBA could be evaluated by the combination of CDU and TCCS, which has a higher diagnostic accuracy of PHA and PIA than PTA. PHA or PIA have typical ultrasonographic manifestations, such as abnormal branches of the internal or external carotid artery on one side, and bilateral hypoplasia of extracranial VA with normal blood flow of ipsilateral intracranial VA and BA.