Basilar Artery Hypoplasia with Embryonic Origin of Anterior Cerebral Arteries: A Radiological Gamut

Abstract

Aims and Objectives: This article aims to determine the most frequent cause of basilar hypoplasia and evaluate the potential impact of associated pathological findings simultaneously. Material and Methods: We have retrospectively reviewed the patients in our archive with basilar hypoplasia and embryonic origin of ACPs. These patients have been studied using 3D TOF with 3D-VR reconstruction. The studies have been carried out using MRI of 1.5 and 3T. Several of them have also undergone cerebral angiography by digital subtraction. Results: The most frequent cause of basilar hypoplasia has been associated with the embryonic origin of both bilateral ACPs with 27 cases. In 3 cases, the basilar artery hypoplasia has been associated with persistent trigeminal artery. In 25 patients studied the basilar hypoplasia was an incidental finding in the context of a routine MRI study including angio MRI sequences. Of the patients studied only 5 had allegedly clinical history that could be related to hypoplastic basilar artery. Conclusion: Hypoplasia of basilar artery is a related variant, in most cases, with both embryonic origins of ACPs. In most of the patients studied, this was an incidental finding. However the said variant may be a predisposing factor to cause any grade of vascular insufficiency in the territory of vertebro-basilar artery. With respect to the aneurysm, associated described persistent trigeminal artery is thought likely may have a causal relationship with this variant.