ABSTRACT
Objective To explore the feature of embryonic communication between the carotid and vertebro-basilar system using MRA of head and neck on MR. Methods The MRA images from 7 246 consecutive patients in Liaocheng People's hospital between June 2009 and December 2015 were retrospectively reviewed. The feature of embryonic communication between internal carotid, external carotid artery and vertebro-basilar system using MRA was analyzed by two doctors. Results Forty-four cases of embryonic communication between the carotid and vertebro-basilar system were found. Thirty-nine cases of primitive trigeminal artery (PTA) and primitive trigeminal artery variants (PTAV) were detected by MRA. The prevalence of both PTA and PTAV was 0.54% (PTA, 27 cases;PTAV, 12 cases). Twenty-three cases of PTA were lateral types;four cases were medial types. All PTA originated from C4 portion of internal carotid artery, of which 27 cases connected with the basilar artery and two cases connected with the superior cerebellar artery. The region of the BA proximal to the site of convergence with the PTA was hypoplastic in seven cases and completely absent in two cases. Three cases of primitive hypoglossal artery and 2 cases of primitive proatlantal artery were detected by MRA. The prevalence of primitive hypoglossal artery and primitive proatlantal artery was 0.04% and 0.03 % respectively. Two cases of primitive hypoglossal artery were from the lateral internal carotid artery and one was from the external carotid artery. It's all on the right side. One case of primitive proatlantal artery was on the left which arises from the external carotid artery, one on the right which originated from the outer part of the internal carotid artery. Thirty-four cases were coexisted with other variants of head and neck vessels. All of the primitive hypoglossal arteries were coexisted with vertebral artery absence. One case of primitive proatlantal intersegmental artery was coexisted with vertebral artery dysplasia. Eighteen cases were associated with cerebral infarctions, and three cases with aneurysm. Conclusions MRA can accurately assess the variants of carotid-vertebasilar anastomoses and have diagnostic significance.
ABSTRACT
Objective To explore the appearance of CT angiography(CTA)and magnetic resonance angiography (MRA)in persis-tent carotid-basilar artery anastomoses,and discuss its clinical significance.Methods 1 7 patients of persistent carotid-basilar artery anastomoses diagnosed by CT and MR angiography were retrospectively reviewed.10 patients were examined by craniocervical CTA, 7 patients were examined by cranial and cervical MRA,and 3 patients were examined by CTA and MRA.Results 10 patients had persistent trigeminal arteries (PTA).Based on Saltzman type:6 cases were Saltzman type Ⅰ,2 cases were Saltzman typeⅡ,and 2 cases were Saltzman type Ⅲ.1 case of 3 persistent hypoglossal arteries(PHA)originated from the right carotid artery,and 2 cases originated from the left external carotid artery.2 cases of 4 proatlantal intersegmental artery(PIA)were right ipsilateral,and 2 cases were left ipsilateral.1 case of PTA and 1 case of PHA associated with an aneurysm.6 cases of PTA,2 cases of PHA and 1 case of PIA complicated with ipsilateral vertebral arteries artopied or hypoplasia of the contralateral vertebral artery.Conclusion CTA and MRA can demonstrate clearly the course of persistent carotid-basilar artery anastomoses and its complicating intracranial coexisting abnormalities.Diagnosis of this anatomic variation may be helpful for providing reliable data to the guidance of surgery and interven-tional treatment.