Hemodynamic Differences Between Basilar Artery Fenestration and Normal Vertebrobasilar Artery: A Pilot Study

Background: Basilar artery fenestration has been proposed as a contributor to ischemic stroke, as unique flow patterns induced by fenestration may be related to thrombus formation or insufficiency. This study aimed to evaluate the hemodynamics of basilar artery fenestration (BAF) using computational fluid dynamics (CFD).Methods: Patients with BAF and normal vertebrobasilar system were recruited and separately evaluated using CFD. Specific geometric vascular models were reconstructed based on 3D-rotational angiography (3D-RA). Patients were divided into the BAF group and control group (i.e., patients with the normal vertebrobasilar system). Hemodynamic and geometric variables were calculated and compared between groups using Student's t-test or Wilcoxon rank-sum test.Results: Overall, 24 patients were included, with 12 patients each in the BAF group and the control group. The BAF group had a significantly smaller basilar artery diameter than the control group (3.1 ± 0.51 vs. 3.76 ± 0.4, p = 0.002). Compared to the control group, the BAF group had higher values of maxOSI (median, 0.3 vs. 0.09, p = 0.028), TAWSSG (median, 983.42 vs. 565.39, p = 0.038) in the flow confluence, higher SAR-TAWSSG in bifurcation (median, 70.22 vs. 27.65, p = 0.002) and higher SAR-TAWSSG in basilar artery (median, 48.75 vs. 16.17, p < 0.001) of the vertebrobasilar artery.Conclusions: This pilot study suggested that hemodynamic differences between BAF and normal vertebrobasilar artery across multiple shear flow parameters. The disturbed flow in the BAF may increase the risk of thrombus formation, plaque instability, and subsequent ischemic cerebrovascular events. These should be confirmed by future studies.

Vertebrobasilar Junction Angle Over 90°: A Potential Imaging Marker Associated With Vertebrobasilar Atherosclerosis

Objective: Whether the cerebral vascular variations play an important role in the progression of intracranial atherosclerosis is yet largely unclear. We aimed to investigate the relationship between the magnitude of the vertebrobasilar junction (VBJ) angle and the imaging features of vertebrobasilar artery atherosclerosis.Methods: Adult patients with acute ischemic stroke or transient ischemic attack undergoing a 3.0-tesla vessel wall magnetic resonance imaging (VW-MRI) scanning were consecutively included. Imaging features of vertebrobasilar artery atherosclerosis were assessed on the reconstructed short axis of VW-MRI at the most stenotic site. The VBJ angle degree was measured on magnetic resonance angiography and classified into the angle ≥90° or <90°.Results: Among 68 patients (mean age = 63.5 ± 9.4 years old; 63.2% were male) with vertebrobasilar atherosclerosis, 33 had a VBJ angle ≥90° and 35 had a VBJ angle <90°. Compared to the vertebrobasilar plaques with VBJ angle <90°, those with VBJ angle ≥90° had a heavier plaque burden (84.35 vs. 70.58%, p < 0.001) and higher prevalence of intraplaque hemorrhage (17.1 vs. 3.3%, p = 0.01). In the regression analyses, the VBJ angle ≥90° was also robustly associated with plaque burden (odds ratio, 1.11; 95% confidential interval, 1.043–1.18; p = 0.001) and intraplaque hemorrhage (odds ratio, 5.776; 95% confidential interval, 1.095–30.46; p = 0.039) of vertebrobasilar atherosclerosis.Conclusion: The VBJ angle over 90° might aggravate the vessel wall condition of the atherosclerotic vertebrobasilar arteries, which might serve as a potential risk factor for vertebrobasilar atherosclerosis.

Vascular supply of the hindbrain: Basic longitudinal and axial angioarchitecture

The basic pattern of arterial vascularization is highly conserved across vertebrates and develops under neuromeric rules. The hindbrain has an angioarchitecture that is homologous to that of the spinal cord, and the hindbrain vascular system can be analyzed at the longitudinal and axial structures. During development, there are two main longitudinal arteries: the longitudinal neural artery and primitive lateral basilovertebral anastomosis. This review discusses the basic pattern of the blood supply of the hindbrain, the development of vascularization, and the anatomical variations, with a special reference to the embryological point of view of two main longitudinal anastomoses (longitudinal neural artery and primitive lateral basilovertebral anastomosis). The formation of commonly observed variations, such as fenestration and duplication of the vertebrobasilar artery, or primitive trigeminal artery variant, can be explained by the partial persistence of the primitive lateral basilovertebral anastomosis. Understanding the pattern and the development of the blood supply of the hindbrain provides useful information of the various anomalies of the vertebrobasilar junction and cerebellar arteries.

Influence of renal impairment on clinical outcomes after endovascular recanalization in vertebrobasilar artery occlusions

BackgroundRenal impairment (RI) is associated with worse outcomes in the treatment of intravenous thrombolysis and emergent endovascular treatment (EVT) in anterior circulation stroke. The objective of this study was to investigate the association of RI with short-term and long-term outcomes in patients with vertebrobasilar artery occlusions (VBAO) who received EVT.MethodsConsecutive patients with VBAO receiving EVT involving 21 stroke centers were retrospectively included. Multivariate regression analyses were used to evaluate the association of RI with mortality and symptomatic intracranial hemorrhage (sICH) during the hospital stay, and also mortality, favorable functional outcome (modified Rankin Scale (mRS) score of 0–3), and functional improvement (shift in mRS score) at 3 months and 1 year follow-up. The association between RI and the risk of recurrent stroke was evaluated with multivariate competing-risk regression analyses.ResultsAfter adjustment for potential confounders, RI was independently associated with sICH (OR 3.30, 95% CI 1.55 to 7.18), as well as mortality (OR 2.54, 95% CI 1.47 to 4.38; OR 3.07, 95% CI 1.72 to 8.08), favorable functional outcome (OR 0.33, 95% CI 0.17 to 0.66; OR 0.25, 95% CI 0.12 to 0.51), and functional improvement (OR 0.45, 95% CI 0.28 to 0.74; OR 0.35, 95% CI 0.21 to 0.60) at 3 months and 1 year follow-up, respectively, but RI was not associated with in-hospital mortality. Additionally, there was no significant association between RI and recurrent stroke within 1 year.ConclusionsOur findings suggest that RI is associated with a higher risk of sICH in hospital and a decrease in survival, favorable functional outcome, and functional improvement at 90 days and 1 year follow-up.Trial registration numberURL: http://www.chictr.org.cn/; Unique identifier: ChiCTR2000033211.

Effect of Electroacupuncture Combined with Guizhi Gegen Decoction on Cervical Vertigo and Its Influence on TCD of Vertebrobasilar Artery, Blood Rheology Indexes, and Quality of Life

Cervical vertigo is a common clinical disease. In this study, we investigated the clinical efficacy of adding the treatment protocol of Gui Zhi Ge Gen Tang and electroacupuncture to the Western medical treatment in cervical vertigo. The results showed that the total effective rate of the study group was higher than that of the control group P < 0.05 . After treatment, the vertigo, headache, neck and shoulder pain, daily life and work, and psychological and social adjustment scores were higher in the study group than in the control group P < 0.05 . LVA, RVA, and VB were higher in the study group than in the control group after treatment P < 0.05 . The whole blood viscosity high cut, whole blood viscosity low cut, and plasma viscosity levels were lower in the study group than in the control group after treatment P < 0.05 . After treatment, PF, RF, RE, BP, GH, VT, SF, MH, and HT were higher in the study group than those before treatment P < 0.05 . The incidence of adverse reactions was not statistically significant in the study group compared with the control group P > 0.05 . This means that electroacupuncture combined with Gui Zhi Ge Gen Tang can effectively increase the blood flow velocity of the vertebrobasilar artery in patients with cervical vertigo and improve their blood rheology and quality of life with definite efficacy and high safety.

Stent Retriever Thrombectomy for Anterior vs. Posterior Circulation Ischemic Stroke: Analysis of the STRATIS Registry

Background and Purpose: The benefits of mechanical thrombectomy (MT) in vertebrobasilar artery occlusions have not been well-studied. We compared clinical, procedural, and safety outcomes of MT for posterior circulation (PC) vs. anterior circulation (AC) occlusions among patients in the STRATIS registry.Methods: Data from STRATIS including patient demographics, procedural characteristics, and outcomes including symptomatic intracranial hemorrhage (sICH) at 24 h, serious adverse events (SAE), substantial reperfusion [modified thrombolysis in cerebral infarction (mTICI) 2b/3], 90-day functional independence [modified Rankin Scale (mRS) 0–2], and 90-day mortality were analyzed. Univariate logistic regression was used to calculate predictors of good clinical outcome.Results: Of 984 STRATIS patients, 43 (4.4%) patients with PC occlusions [mean age 63.0 ± 13.6, 25.6% (11/43) female] and 932 (94.7%) with AC occlusions [mean age 68.5 ± 14.8, 46.9% (437/932) female] were included for analysis. Median National Institutes of Health Stroke Scale (NIHSS) scores at baseline were 17.0 (13.0, 12.0) for the AC group and 12.0 (11.0, 24.0) for the PC group. Time from onset to procedure end was longer for the PC group [median (IQR): 322.0 min (255.0–421.0) vs. 271.0 min (207.0–360.0); p = 0.007]. PC and AC groups had similar rates of substantial reperfusion [89.2% (33/37) vs. 87.7% (684/780)], procedure-related SAE [0.0% (0/43) vs. 1.7% (16/932)], sICH [0.0% (0/38) vs. 1.5% (12/795)], 90-day functional independence [66.7% (26/39) vs. 55.9% (480/858)] and mortality [12.8% (5/39) vs. 15.8% (136/861)]. National Institutes of Health Stroke Scale score and patient sex were significant univariate predictors of good clinical outcome (p &lt; 0.05).Conclusions: Despite longer reperfusion times, MT in PC stroke has similar rates of 90-day functional independence with no significant difference in procedure-related SAE, sICH, or mortality, supporting the use of MT in PC acute ischemic stroke (AIS).Clinical Trial Registration:https://www.clinicaltrials.gov, Identifier: NCT02239640.