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Aim: Development of atherosclerotic plaques is affected by vascular geometry and hemodynamics. Hemodynamics in the basilar artery (BA) is unique as the flow converges from vertebral arteries (VAs). Here, we investigated the characteristics of BA plaque based on VA and BA geometry., Methods: Consecutive patients evaluated using high-resolution magnetic resonance imaging (MRI) at a general health center were screened. Geometric characteristics of VA (VA dominancy and VA-BA angles) and BA (BA convexity and BA angles) were assessed. The burden of BA plaques was investigated in each wall (anterior, posterior, left, and right lateral). The characteristics of BA plaques were compared according to VA dominancy (right vs. left), BA angle of lateral view (lateral mid-BA angle; dichotomized), and total plaque burden (divided by tertiles)., Results: Of the 1029 subjects, BA plaques were observed in 98 (9.5%) patients, and were more frequently located at the anterior wall (32.4%) and posterior wall (35.0%) than the right wall (15.3%) and left lateral wall (17.6%). Right and left lateral plaques were more frequent in the left and right convex BA, respectively (p=0.009 and p=0.024, respectively). Anterior plaques were more frequently observed in low lateral mid-BA angle (p= 0.043). BA plaques were predominant in anterior and posterior walls in patients with lower plaque burden, whereas they were predominant in right and left lateral walls in patients with higher plaque burden (p=0.001 and p=0.025, respectively)., Conclusions: Asymptomatic BA plaque location was associated with BA convexity and lateral mid-BA angle. The anteriorly and posteriorly located BA plaques may extend to the lateral walls as the plaque burden increases.

Objective: Intracranial aneurysm (IA) is the leading cause of subarachnoid hemorrhage. The pathomechanisms of IA are poorly understood but can be related to arterial tortuosity resulting from underlying systemic factors leading to arterial wall weakening. We aimed to analyze the tortuosity of the intracranial artery in a cohort with IA, hypothesizing that the tortuosity of intracranial arteries differs depending on the characteristics of the IA., Methods: Patients with saccular IA were consecutively enrolled. Clinical factors and vascular tortuosity of the right and left middle cerebral arteries and basilar artery (BA) of all patients with IA were compared according to the characteristics of the IA: 1) ruptured versus unruptured, 2) multiple versus single, and 3) large (>5 cm) versus small (≤5 cm). Unruptured IAs were comparatively analyzed according to aneurysm size and aspect ratio, whereas ruptured IAs were analyzed according to aneurysm size., Results: Two hundred eighty-five patients were enrolled (mean age, 59 years; 71.2% women). The tortuosity of the BA was higher in the large IA group (5.63 ± 6.26; n = 133; P = 0.009), large unruptured IA group (6.64 ± 6.32; n = 53; P = 0.039), and large ruptured IA group (5.50 ± 6.52; n = 80; P = 0.033) compared with the small IA, small unruptured IA, and small ruptured IA group. In multivariate analysis, increased BA tortuosity was significantly associated with large IAs (β = 1.066; P = 0.008), unruptured large IAs (β = 1.077; P = 0.033), and ruptured large IAs (β = 1.086; P = 0.025)., Conclusions: The BA tortuosity was higher in patients with large IAs, which may represent an imaging biomarker of aneurysm growth., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Background: The association between progressive motor deficits (PMD) in acute pontine infarction and basilar stenosis is unclear. High resolution MRI (HRMRI) is an emerging tool for basilar artery evaluation and might provide more accurate information. We aimed to analyze the association between basilar plaque assessed by HRMRI and PMD after acute pontine infarction., Methods: We identified consecutive patients with unilateral pontine infarction within 24 h of stroke onset. All the patients underwent diffusion weighted MRI, MR angiography and HRMRI within 24 h of admission. PMD was defined as an increase in National Institutes of Health Stroke Scale score by ≥1 during hospitalization. Factors potentially associated with PMD were validated by multivariate analyses., Results: Of a total of 87 patients, 63 (72%) had paramedian pontine infarction (PPI) and PMD was observed in 28 (32%) patients. Apparent basilar plaque assessed by HRMRI was more frequent in those with PMD than in those without PMD (52% versus 33%, p<0.001). In contrast, the frequency of basilar stenosis (>30%) assessed by MR angiography was similar regardless of PMD. In the patients with PPI, PMD was associated with hypertension and apparent plaque on HRMRI. After adjusting covariates, PMD was independently associated with apparent plaque on HRMRI (OR, 9.1; 95% CI 1.4-58.9)., Conclusions: Our results suggest that basilar plaque assessed by HRMRI is associated with PMD in patients with acute unilateral pontine infarction. Since basilar stenosis may be underestimated by MR angiography, HRMRI may provide additional information for predicting PMD and evaluating basilar artery stenosis., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)

Objective: Intracranial atherosclerosis (ICAS) is a major cause of ischemic stroke; however it is rather neglected. Vessel wall visualization by high resolution magnetic resonance imaging (HRMRI) might provide more accurate information., Methods: A total of 219 consecutive patients with acute ischemic stroke underwent MRI, MRA and proton-density weighted HRMRI. Using HRMRI, the patients were divided into 3 groups with respect to basilar plaques: no plaque (n = 85), minimal plaque (n = 72) and apparent plaque (n = 62). Demographics and characteristics were compared between the groups, and the extents of stenoses calculated from MRA versus HRMRI data were also compared. Factors potentially associated with basilar plaque were validated by multivariate analysis., Results: Patients with apparent plaque had higher frequencies of diabetes mellitus, lower high-density lipoprotein and higher hemoglobin A1c, erythrocyte sedimentation rate and homocysteine. Of the 62 cases of apparent plaque, severe stenosis (>50%) was observed in 10 (16%) by MRA and in 27 (43%) by HRMRI, which points to overestimation of plaques by HRMRI. In addition, no stenosis was evident on MRA in 13 patients with apparent plaque even though they had up to 72% stenosis on HRMRI. After adjusting for covariates, basilar artery apparent plaque was independently associated with old age, previous stroke, diabetes mellitus, low HDL and high levels of homocysteine., Conclusions: Basilar artery stenosis with plaque is more accurately detected using HRMRI than MRA. In addition, the associated risk factors differ somewhat. The use of HRMRI for evaluating ICAS deserves more attention., (Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.)

Two different stroke mechanisms are involved in small vessel disease: branch atheromatous disease (BAD) and lipohyalinotic degeneration (LD). We compared mechanisms of stroke in lenticulostriate arteries (LSA) vs. anterior pontine arteries (APA) and verified factors associated with stroke mechanisms, including shape of middle cerebral artery (MCA) and basilar artery (BA). We retrospectively reviewed patients with acute ischemic stroke with penetrating artery territory confirmed by MRI. The mechanisms of stroke were categorized based on diffusion-weighted imaging; BAD was defined as lesion larger than 10 mm in LSA and lesions involving basal pontine in APA. Other lesions were classified as LD. The shapes of MCA and BA were classified as straight, with one angle, or with two angles (U, C or S shape, respectively) using anterior–posterior view. The study included 221 patients. LD was more common in LSA infarcts, but BAD was more common in APA infarcts (p < 0.001). Low initial National Institutes of Health Stroke Scale [Adjusted Odds ratio (aOR) = 0.78; p < 0.001], absence of hyperlipidemia [aOR = 0.31; p = 0.002], previous statin use [aOR = 4.35; p = 0.028] LSA infarcts [reference = APA territory; aOR = 11.07; p < 0.001], and S-shaped vessels (reference = straight shaped vessels; aOR = 3.51; p = 0.004) were independently associated with LD. Angulations in the mother vessels may be more associated with true small vessel disease more with LD than BAD. [ABSTRACT FROM AUTHOR]