Boleaga-Durán B, Ameller-Terrazas S, Criales-Cortés JL

Language: Spanish
References: 17
Page: 239-249
PDF size: 342.36 Kb.

ABSTRACT

Introduction: Anatomic variants of brain arteries, including carotid-vertebral anastomosis, are adequately assessed with Magnetic Resonance angiography (MRa).
Purpose: This work is aimed at defining, through MRa, the anatomic variants of the brain base artery circle and aberrant vessels of the head and neck.
Material and Methods: MRa was performed to 412 patients, 177 males and 235 females, with a 1.5T MR equipment, with 3D TOF images.
Results: The MRa studies did not show any anatomic variants in 38 patients (9.22%). In 168 cases (40.7%) there was blood flow reduction due to ACoP hypoplasia. In 49 patients (11.8%) right ACoP hypoplasia was observed, while in 51 patients (12.3%) the hypoplasia was of the left ACoP. 30 patients (7.2%) had hypoplasia of the right anterior brain artery (ABA) and 10 patients in the left ABA (2.4%). Hypoplasia of the initial part of ACP or P1 in 34 cases (8.2%) and its association with hypoplasia of ABA in 29 cases (7.2%). Persistent primitive trigeminal artery (PTA) in two cases (0.4%) and azygous vein only in one patient (0.2%).
Discussion: The artery circle in the brain base and the carotid vertebral basilar anastomosis (CVBA) have characteristics recognizable by means of MRa that enable their identification. CVBA usually have tour branches, known as intersegmentary: trigeminal artery, otic artery (acoustic), hypoglossal artery and pro atloid artery. An azygous anterior brain artery (ABA) is a lonely odd vessel originated in one trunk where the two ABA meet with the horizontal segment (A1). There are other less frequent abnormal branches of the internal carotid artery (ICA), such as: persistent dorsal ophthalmic artery, anastomosis of the internal carotid with the anterior brain artery, fetal origin of the back brain artery, hyperplasic anterior choroidea artery, duplicated media cerebral artery and persistent primitive olfactory artery.
Conclusion: High sensitivity and specificity of MRa enables the assessment of the anatomic variants of the artery circle in the base of the brain and the CVBA.

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