Relationship between the geometry patterns of vertebrobasilar artery and atherosclerosis

Abstract

BackgroundThe plaques at the dorsal or lateral wall of basilar artery (BA) are associated with pontine infarcts. We sought to explore the correlations between vertebrobasilar artery geometry and BA plaque locations.MethodsWe retrospectively analyzed the imaging and clinical data of 84 patients with BA atherosclerosis. On three-dimensional time-of-flight images, a side to side diameter difference of bilateral vertebral artery (VA) and BA bending were assessed. The vertebrobasilar artery geometry was qualitatively classified into four basic configurations: Walking, Tuning Fork, Dominant-Lambda, and Hypoplasia-Lambda. On high-resolution magnetic resonance imaging, the plaques were categorized based on the involvement of the ventral, dorsal, or lateral sides of BA wall. The relationships between vertebrobasilar artery geometry parameters and plaque locations were analyzed.ResultsLeft VA dominance was identified in 28(33%) patients, and right VA dominance in 22(26%) patients. BA bending were detected in 49 patients. There were no significant correlations between the diameter difference/ratio of VA diameters and plaque locations, or between BA bending and plaque locations. BA plaques were evenly distributed in the vertebrobasilar arteries with Tuning Fork and Dominant-Lambda configurations. In Hypoplasia-Lambda group, however, plaques were more frequently located at the dorsal wall (58.57%) than at the ventral (14.43%) and lateral wall (26.71%; P = 0.001). In Walking group, the plaques more likely occurred at the lateral (49.79%) and dorsal (35.07%) wall than at the ventral wall (14.86%, P = 0.02).ConclusionsThe geometric configurations of vertebrobasilar artery strongly influence the BA plaque locations. Further prospective studies are warranted to testify whether Hypoplasia-Lambda and Walking configurations are independent risk factors for pontine infarcts.Electronic supplementary materialThe online version of this article (10.1186/s12883-018-1084-6) contains supplementary material, which is available to authorized users.

Vertebrobasilar Artery Geometry and Basilar Artery Plaques: A High-Resolution Magnetic Resonance Imaging Study

“…Yu et al [16] have investigated the relationship between the geometry patterns of vertebrobasilar artery and atherosclerosis. In their study, the vertebrobasilar artery geometry was qualitatively classi ed into four basic con gurations: Walking, Tuning, Dominant-Lambda, and Hypoplasia-Lambda.…”

“…The diameter of the VA was measured on 3D-TOF-MRA. The diameter of each vessel was calculated as the average of the measurements made at three consecutive points, 3 mm apart, starting from the vertebrobasilar junction (for both VAs and the BA) [16,20]. The dominant VA was de ned as: the diameter of the VA on the dominant side was wider than that of the contralateral VA (difference in diameter ≥ 0.3 mm) [16,20].…”

“…The Walking geometry is distinguished by two VAs with a diameter difference of less than 0.3 mm that bend in the same direction before merging into the BA [16,17]. The Tuning Fork shows two VAs of equal diameter (difference in diameter < 0.3 mm) that bend in opposite directions to form a symmetrical con uence from which the BA emerges [16,17]. The Lambda geometry is de ned as two VAs with a diameter difference of at least 0.3 mm that merge into the BA [16,17].…”

“…The Tuning Fork shows two VAs of equal diameter (difference in diameter < 0.3 mm) that bend in opposite directions to form a symmetrical con uence from which the BA emerges [16,17]. The Lambda geometry is de ned as two VAs with a diameter difference of at least 0.3 mm that merge into the BA [16,17]. In the No Con uence con guration, the VAs are not merged, but one VA continues as the BA, and the other VA feeds into other arteries, mostly the posterior inferior cerebellar artery.…”

“…The vertebrobasilar artery (VBA) system is unique in human anatomy in that two arteries (the left and right vertebral artery (VA)) merge into one artery (basilar artery (BA)). The diameters of the left and right VA differ in up to 50% of people [16], and their anatomical course is also different. Vertebrobasilar geometry can be classi ed into distinct con gurations according to the anatomical course of the VA on either side and the difference in their diameters.…”