Geometrical characteristics associated with atherosclerotic disease in the basilar artery: a magnetic resonance vessel wall imaging study

Abstract

Background: Vascular geometry may play an important role in the development of atherosclerosis. This study aimed to investigate the relationships between the geometrical characteristics of basilar artery (BA) and the presence, burden, and distribution of BA plaques using magnetic resonance vessel wall imaging.Methods: Patients with cerebrovascular symptoms in the posterior circulation were recruited and underwent magnetic resonance imaging. The BA's geometrical characteristics, including actual length, straightened length, tortuosity, lateral basilar artery-vertebral artery (VA) angle, lateral mid-BA angle, and BA convexity, were measured. The presence of plaques, stenosis, and plaque burden, including mean and maximal wall thickness, were evaluated. The BA's cross-sectional vessel wall was divided into 4 quadrants: dorsal, ventral, right, and left quadrant. The distribution of BA plaques was analyzed.Results: Of 344 recruited patients (mean age: 68.1±11.1 years; 200 males), 100 (29.1%) had BA plaques.Patients with BA plaques had higher tortuosity of the BA (13.6±9.0 vs. 9.7±7.7, P<0.001) compared to those without BA plaques. Multivariate regression analysis showed that tortuosity of the BA was associated with the presence of BA plaques (OR, 1.641; 95% CI, 1.232 to 2.186; P=0.001) and mean wall thickness (β, 0.045; 95% CI, 0.008 to 0.081; P=0.017). The plaque distribution in the left wall and right wall of BA was more frequent in patients with right (P=0.006) and left (P<0.001) convex BA, respectively.Conclusions: The BA's geometrical characteristics, particularly tortuosity and convexity, are independently associated with the presence, burden, and distribution of plaques in the BA.

Effect of Mid-Basilar Artery Angle and Plaque Characteristics on Pontine Infarction in Patients with Basilar Artery Plaque

“…Recent studies have used BA vascular geometrical risk factors to explain the presence and location of plaques 16) . For example, high tortuosity was associated with atherosclerotic plaques in the middle cerebral artery 17) , BA 18) , and superficial femoral artery 19) . BA plaques were frequently distributed in the lateral walls in symptomatic patients 18) .…”

“…For example, high tortuosity was associated with atherosclerotic plaques in the middle cerebral artery 17) , BA 18) , and superficial femoral artery 19) . BA plaques were frequently distributed in the lateral walls in symptomatic patients 18) . Asymptomatic BA plaques were demonstrated in 9.5% of individuals who underwent HRMRI during a routine health check-up 16) .…”

“…Asymptomatic BA plaques were demonstrated in 9.5% of individuals who underwent HRMRI during a routine health check-up 16) . Furthermore, the influence of the BA curvature on the presence and location of plaques has been found to be helpful in explaining the mechanism of infarct occurrence [17][18][19] , but the effects of the presence and location of plaques on the occurrence of infarcts have not yet been studied. In the present study, we used HRMRI and three-dimensional timeof-flight magnetic resonance angiography (3D-TOF-MRA) to investigate (a) plaque characteristics that serve as risk factors for pontine infarction in patients with BA plaques, (b) the correlation of the mid-BA angle and BA plaque characteristics, and (c) the association between the mid-BA angle and pontine infarction.…”

“…Most previous studies mainly focused on the relationship between the tortuosity of the BA and the plaque presence, location, and mean wall thickness 14,16,18,38) , or they only focused on differentiating plaque characteristics on HRMRI between symptomatic and asymptomatic patients 39) . However, very few studies have established the relationship between different mid-BA angle and plaque characteristics and pontine infarction when the BA has plaques.…”

Clinical Relevance of Plaque Distribution for Basilar Artery Stenosis

“…The distribution of atherosclerotic plaques is associated with the risk of ischemic events. [5][6][7] For example, it is more likely that atherosclerotic plaques located near perforating orifices are symptomatic during stent placement and may have a "snow plowing" effect. 8 Several postmortem studies have demonstrated that basilar artery perforators typically originate from the lateral and dorsal walls of the segment, distal from the anterior-inferior cerebellar artery, possibly explaining the high rate of postoperative complications.…”