Endovascular Thrombectomy for a Progressive Stroke Patient With a High-Burden Carotid Free-Floating Thrombus.

Carotid free-floating thrombus (FFT) is a rare cause of acute ischemic events. The optimal management of carotid FFT remains unclear. The optimal and individualized management of carotid FFT should be determined based on the underlying etiology, clinical manifestation, and imaging characteristics. we reported a case with endovascular thrombectomy for a progressive stroke patient with a high-burden carotid free-floating thrombus. ANN NEUROL 2024;95:362-364.

New Diffusion Abnormalities Following Endovascular Treatment for Intracranial Atherosclerosis.

Background There are limited data on new ischemic brain lesions after endovascular treatment for symptomatic intracranial atherosclerotic stenosis (ICAS). Purpose To investigate the (a) characteristics of new ischemic brain lesions at diffusion-weighted MRI (new diffusion abnormalities) after endovascular treatment, (b) characteristics between those treated with balloon angioplasty and stent placement procedures, and (c) predictors of new ischemic brain lesions. Materials and Methods Patients with symptomatic ICAS in whom maximum medical therapy failed were prospectively enrolled between April 2020 and July 2021 from a national stroke center and underwent endovascular treatment. All study participants underwent thin-section diffusion-weighted MRI (voxel size, 1.4 × 1.4 × 2 mm3 with no section gap) before and after treatment. The characteristics of new ischemic brain lesions were recorded. Multivariable logistic regression analysis was performed to determine potential predictors of new ischemic brain lesions. Results A total of 119 study participants (mean age, 59 years ± 11 [SD]; 81 men; 70 treated with balloon angioplasty and 49 with stent placement) were enrolled. Of the 119 participants, 77 (65%) had new ischemic brain lesions. Five of the 119 participants (4%) had symptomatic ischemic stroke. New ischemic brain lesions were located in (61%, 72 of 119) and/or beyond (35%, 41 of 119) the territory of the treated artery. Of the 77 participants with new ischemic brain lesions, 58 (75%) had lesions located in peripheral brain areas. There was no evidence of a difference in the frequency of new ischemic brain lesions between the balloon angioplasty and stent groups (60% vs 71%, P = .20). In adjusted models, cigarette smoking (odds ratio [OR], 3.6; 95% CI: 1.3, 9.7) and more than one operative attempt (OR, 2.9; 95% CI: 1.2, 7.0) were independent predictors of new ischemic brain lesions. Conclusion New ischemic brain lesions on diffusion-weighted MRI scans were common after endovascular treatment for symptomatic intracranial atherosclerotic stenosis, and occurrence may be associated with cigarette smoking and the number of operative attempts. Clinical trial registration no. ChiCTR2100052925 © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Russell in this issue.

Association of Perforator Stroke After Basilar Artery Stenting With Negative Remodeling.

Background and Purpose- We try to evaluate whether plaque features and perforator stroke after intracranial stenting is associated with the arterial remodeling patterns in patients with severe basilar artery stenosis. Methods- We studied patients with symptomatic intracranial arterial stenosis who underwent high-resolution magnetic resonance imaging from September 2014 to January 2017. Among them, patients with basilar artery stenosis underwent angioplasty and stenting were recruited. Arterial remodeling patterns were divided into negative or nonnegative remodeling. Plaque features were investigated by high-resolution magnetic resonance imaging, which includes plaque distribution, intraplaque hemorrhage, calcification, as well as enhancement patterns. Incidence of perforator strokes after intracranial stenting was recorded. Plaque features and incidence of poststenting perforator stroke were compared between negative and nonnegative remodeling. Results- Two hundred ninety-eight consecutive patients were enrolled. Among them, 30 patients fulfilled the inclusion criteria. There were 11 patients (36.7%) with negative remodeling and 19 (63.3%) with nonnegative remodeling. Twenty-six patients (86.7%) had diffuse distribution, 5 patients (16.7%) had intraplaque hemorrhage, 2 patients (6.7%) had calcification, and 17 patients (65.4%) had enhancement. Three patients had perforator stroke after stenting. Plaque features were similar between negative and nonnegative remodeling groups. Patients with negative remodeling were more likely to have perforator stroke after stenting comparing with patients with nonnegative remodeling (27.3% versus 0%, P=0.041). Conclusions- Perforator stroke after basilar artery stenting may be related to negative remodeling on high-resolution magnetic resonance imaging. The finding needs to be confirmed in future studies. Clinical Trial Registration- URL: https://www.clinicaltrials.gov . Unique identifier: NCT02705599.

Association between basilar artery configuration and Vessel Wall features: a prospective high-resolution magnetic resonance imaging study.

BACKGROUND: The relationship between intracranial vessel configuration and wall features remains poorly investigated. Therefore, we aimed to investigate the relationship between the distal and proximal anatomical configuration of basilar artery (BA) and BA vessel wall features on high-resolution magnetic resonance imaging (HRMRI). METHODS: From September 2014 to January 2017, patients with suspected symptomatic intracranial arterial stenosis underwent HRMRI. Patients with severe BA stenosis were selected for this prospective study and divided into two groups corresponding to complete and incomplete BA configuration based on characteristics of the bilateral vertebral arteries and posterior cerebral arteries. Culprit blood vessel wall features on HRMRI included plaque enhancement, intraplaque hemorrhage, remodeling patterns, and plaque distribution. Culprit vessel wall features were compared between patients in the complete and incomplete BA configuration groups. RESULTS: Among the 298 consecutively enrolled patients, 34 had severe BA stenosis. Twenty patients had complete anatomical BA configuration and another 14 of them displayed incomplete configuration. There were no significant differences in vessel wall features between the complete and incomplete configuration patient groups. However, the proximal configuration of BA was associated with intraplaque hemorrhage (p = 0.002) while the distal configuration of BA correlated with strong enhancement of BA plaque (p = 0.041). CONCLUSIONS: No association was found between the complete and incomplete BA configuration groups and blood vessel wall features. The proximal configuration of BA was related with intraplaque hemorrhage and the distal configuration of BA was associated with strong plaque enhancement. Further studies are warranted to confirm these findings. TRIAL REGISTRATION: URL: Unique identifier: NCT02705599 (March 10, 2016).

Semi-automatic computed tomography angiography quantification assessment is an alternative method to digital subtraction angiography in intracranial stenosis: a multicenter study.

Background: The recent randomized controlled trials studying intracranial atherosclerotic stenosis (ICAS) have used digital subtraction angiography (DSA) to quantify stenosis and enroll patients. However, some disadvantages of DSA such as invasive features, contrast agent overuse, and X-ray radiation overexposure, were not considered in these studies. This study aimed to explore whether computed tomography angiography (CTA) with semi-automatic analysis could be an alternative method to DSA in quantifying the absolute stenotic degree in clinical trials. Methods: Patients with 50-99% ICAS were consecutively screened, prospectively enrolled, and underwent CTA and DSA between March 2021 and December 2021 at 6 centers. This study was registered at www.chictr.org.cn (ChiCTR2100052925). The absolute stenotic degree of ICAS on CTA with semi-automatic analysis was calculated by several protocols using minimal/maximum/mean diameters of stenosis and reference site from a semi-automatic analysis software. Intraclass correlation coefficient (ICC) was used to evaluate the reliabilities of quantifying stenotic degree on CTA. The optimal protocol for quantifying ICAS on CTA was explored. The agreements of quantifying ICAS in calcified or non-calcified lesions and 50-69% or 70-99% stenosis on CTA and DSA were assessed. Results: A total of 191 participants (58.8±10.7 years; 148 men) with 202 lesions were enrolled. The optimal protocol for quantifying ICAS on CTA was calculated as (1 - the minimal diameter of stenosis/the mean diameter of reference) × 100% for its highest agreement with DSA [ICC, 0.955, 95% confidence interval (CI): 0.944-0.966, P<0.001]. Among the 202 lesions, 80.2% (162/202) exhibited severe stenosis on DSA. The accuracy of CTA in detecting severe ICAS was excellent (sensitivity =95.1%, positive predictive value =98.1%). The agreements between DSA and CTA in non-calcified lesions (ICC, 0.960 vs. 0.849) and severe stenosis (ICC, 0.918 vs. 0.841) were higher than those in calcified lesions and moderate stenosis. Conclusions: CTA with semi-automatic analysis demonstrated an excellent agreement with DSA in quantifying ICAS, making it promising to replace DSA for the measurement of absolute stenotic degree in clinical trials.

Impact of cerebral small vessel disease on symptomatic in-stent restenosis in intracranial atherosclerosis.

OBJECTIVE: Cerebral small vessel disease (CSVD) commonly coexists with intracranial atherosclerotic stenosis (ICAS). In-stent restenosis (ISR) affects the nonprocedural outcome of severe symptomatic ICAS after intracranial stenting. However, only 8%-27% of ISR patients are symptomatic, which highlights the importance of the investigation of risk factors associated with symptomatic ISR (SISR) to improve long-term functional outcome. Whether CSVD is associated with SISR remains unclear. The authors tested the hypothesis that CSVD is associated with SISR in ICAS patients after intracranial stenting. METHODS: This retrospective study enrolled 97 patients who were symptomatic due to severe anterior circulation ICAS treated with intracranial stenting. SISR was evaluated with clinical and vascular imaging follow-up. CSVD subtypes, including white matter hyperintensities (WMHs), enlarged perivascular spaces, and chronic lacunar infarctions, were evaluated. Cox regression analysis was used to compare the incidence of SISR between patients with and without CSVD. RESULTS: Of the enrolled patients, 58.8% had CSVD. The 1- and 2-year ISR rates were 24.7% and 37.1%, respectively. Of the CSVD subtypes, SISR was associated with deep WMHs (DWMHs; HR 5.39, 95% CI 1.02-28.44). DWMH Fazekas scale grades 2 (HR 85.54, 95% CI 2.42-3018.93) and 3 (HR 66.24, 95% CI 1.87-2352.32) were associated with SISR, but DWMH Fazekas grades 0 and 1 were not. The proportions of SISR in patients with DWMH Fazekas grades 0, 1, 2, and 3 were 16.7%, 33.3%, 50%, and 100%, respectively. CONCLUSIONS: Patients with CSVD have a higher risk of SISR than those without CSVD. Of the CSVD subtypes, patients with DWMHs are associated with SISR. The DWMH Fazekas scale score is considered to be a predictor for SISR.

High-Resolution Magnetic Resonance Imaging in Endovascular Treatment of Vertebrobasilar Junction Stenosis.

INTRODUCTION: Vertebrobasilar junction (VBJ) stenosis is a challenge in endovascular treatment due to structural variants and complexities. The role of high-resolution magnetic resonance imaging (HRMRI) in endovascular treatment for patients with severe VBJ stenosis is uncertain. CASE REPORT: Four patients with symptomatic VBJ stenosis underwent HRMRI of the vessel wall before endovascular treatment. In 3 patients, the VBJ could not be visualized on luminal imaging. One of them had a hypoplastic artery and 2 of them had severe stenotic arteries on HRMRI. HRMRI showed an artery with a negative remodeling in a patient with a hypoplastic vertebral artery. One patient had intraplaque hemorrhage and calcification, and 2 patients had calcification in VBJ lesions. Endovascular treatment was performed utilizing HRMRI findings to guide the decision-making process. CONCLUSION: HRMRI provides additional information about the structure and angle of the VBJ, the characteristics and vulnerability of the plaques, and the lesion size, thus helping to improve the operation process and reduce the risk of complications.

Residual inflammatory risk predicts long-term outcomes following stenting for symptomatic intracranial atherosclerotic stenosis.

BACKGROUND AND PURPOSE: Residual inflammatory risk (RIR) can predict the unfavourable outcomes in patients with minor ischaemic stroke. However, the impact of preprocedural RIR on long-term outcomes in patients with symptomatic intracranial atherosclerotic stenosis (sICAS) who underwent stenting remains understudied. METHODS: This retrospective, single-centre cohort study evaluated consecutive patients with severe sICAS who underwent intracranial stenting. Patients were categorised into four groups based on preprocedural high-sensitivity C-reactive protein (hs-CRP) and low-density lipoprotein cholesterol (LDL-C): residual cholesterol inflammatory risk (RCIR, hs-CRP ≥3 mg/L and LDL-C ≥2.6 mmol/L), RIR (hs-CRP ≥3 mg/L and LDL-C <2.6 mmol/L), residual cholesterol risk (RCR, hs-CRP <3 mg/L and LDL-C ≥2.6 mmol/L) and no residual risk (NRR, hs-CRP <3 mg/L and LDL-C <2.6 mmol/L). The long-term clinical outcomes included recurrent ischaemic stroke and death. The long-term imaging outcomes consisted of in-stent restenosis (ISR) and symptomatic ISR (sISR) after stenting. RESULTS: In this study, 952 patients were included, with 751 (78.9%) being male. Forty-six cases were categorised into the RCIR group, 211 into the RIR group, 107 into the RCR group and 588 into the NRR group. Patients with RCIR (adjusted HR 6.163; 95% CI 2.603 to 14.589; p<0.001) and RIR (adjusted HR 2.205; 95% CI 1.294 to 3.757; p=0.004) had higher risks of recurrent ischaemic stroke than those with NRR during the 54 months of median follow-up time. Patients with RCIR (adjusted HR 3.604; 95% CI 1.431 to 9.072; p=0.007) were more likely to occur ISR, and patients in the RIR group showed a significant increase in the risk of sISR (adjusted HR 2.402; 95% CI 1.078 to 5.351; p=0.032) compared with those in the NRR group with a median follow-up time of 11.9 months. CONCLUSIONS: In patients with sICAS, preprocedural RIR may predict long-term recurrent ischaemic stroke, ISR and sISR following intracranial stenting.

Association between basilar artery stenosis features, vertebral artery stenosis and perforator stroke after stenting.

BACKGROUND AND PURPOSE: We investigated the relationship between basilar artery (BA) atherosclerotic stenosis features and vertebral artery (VA) stenosis and explored whether BA stenosis features are associated with perforator stroke after stenting. METHODS: Patients with BA stenosis who underwent HRMRI and DSA were recruited. Patients were divided into proximal BA stenosis and middle-or-distal BA stenosis groups, and then subgroup analyses were performed based on whether they had VA stenosis. BA plaque features were evaluated by HRMRI. Artery stenosis was measured by DSA. The incidence of perforator stroke after BA stenting was recorded, and the potential association between BA stenosis features and perforator stroke was analyzed. RESULTS: One hundred and seventy-four patients were consecutively enrolled. Patients with proximal BA stenosis had a higher proportion of severe stenosis than those with middle-or-distal BA stenosis (P = 0.027). In the subgroup analysis, this difference mainly existed in patients complicated with VA stenosis (P = 0.023). Patients with proximal BA stenosis had a higher proportion of strong plaque enhancement than those with middle-or-distal BA stenosis (P < 0.001), especially in those with vertebrobasilar junction (VBJ) stenosis (P < 0.001). Perforator stroke after BA stenting occurred in five patients, of whom four had lateral wall BA plaques, four had plaque enhancement and four had proximal BA stenosis. CONCLUSION: Patients with proximal BA stenosis had a higher proportion of severe stenosis and strong plaque enhancement, particularly in patients complicated with VA stenosis and VBJ stenosis. Perforator stroke after BA stenting may be related to distribution, burden and characteristics of BA lesions.

Predictors of hyperperfusion syndrome after stent implantation in symptomatic intracranial atherosclerotic stenosis.

Background: Hyperperfusion syndrome (HPS) is a serious complication after stent implantation in symptomatic intracranial atherosclerotic stenosis (ICAS). This study aims to explore the predictive value of preprocedural computed tomography perfusion (CTP) for HPS after intracranial stenting. Methods: In this retrospective case-control study we collected data from consecutive patients from June 2012 to September 2019 who underwent stent implantation due to severe symptomatic ICAS. Patients who underwent CTP before the procedure were enrolled. CTP was postprocessed using the automated RAPID software to assess the preoperative cerebral perfusion. According to the presence or absence of HPS, the patients were classified into two groups: the HPS group and the non-HPS group. The baseline data, lesion characteristics, and preoperative CTP parameters between the two groups were compared. The receiver operating characteristic (ROC) curve analysis was performed to determine the optimal predictor of HPS. Results: Among the 170 eligible patients, 6 patients (3.53%) had HPS, including 3 who presented with intracranial hemorrhages (ICHs), 1 who had dysphoria, 1 who had delirium, and 1 who had a headache. There were no significant differences in baseline and lesion characteristics between the HPS and non-HPS groups. Compared with the non-HPS group, the HPS group had a significantly higher volume of time-to-maximum (Tmax) >4 s (429.5 vs. 93 mL; P=0.006) and Tmax >6 s (200 vs. 0 mL; P=0.003). The optimal volume threshold for maximizing sensitivity in predicting HPS was 65.5 mL with Tmax >4 s [area under the curve (AUC), 0.832; 95% confidence interval (CI): 0.650 to 1.000; P=0.006]. Conclusions: Tmax >4 s volume may be a predictor of HPS after stent implantation in symptomatic ICAS. Further prospective studies should be conducted to confirm our conclusion.

Association of periprocedural perfusion non-improvement with recurrent stroke after endovascular treatment for Intracranial Atherosclerotic Stenosis.

Background: Predictors of recurrent stroke after endovascular treatment for symptomatic intracranial atherosclerotic stenosis (ICAS) remain uncertain. Objectives: Among baseline characteristics, lesion features, and cerebral perfusion changes, we try to explore which factors are associated with the risk of recurrent stroke in symptomatic ICAS after endovascular treatment. Design: Consecutive patients with symptomatic ICAS of 70-99% receiving endovascular treatment were enrolled. All patients underwent whole-brain computer tomography perfusion (CTP) within 3 days before and 3 days after the endovascular treatment. Baseline characteristics, lesion features, and cerebral perfusion changes were collected. Methods: Cerebral perfusion changes were evaluated with RAPID software and calculated as preprocedural cerebral blood flow (CBF) < 30%, time to maximum of the residue function (Tmax) > 6 s, and Tmax > 4 s volumes minus postprocedural. Cerebral perfusion changes were divided into periprocedural perfusion improvement (>0 ml) and non-improvement (⩽ 0 ml). Recurrent stroke within 180 days was collected. The Cox proportional hazards analysis analyses were performed to evaluate factors associated with recurrent stroke. Results: From March 2021 to December 2021, 107 patients with symptomatic ICAS were enrolled. Of the 107 enrolled patients, 30 (28.0%) patients underwent balloon angioplasty alone and 77 patients (72.0%) underwent stenting. The perioperative complications occurred in three patients. Among CBF < 30%, Tmax > 6 s, and Tmax > 4 s volumes, Tmax > 4 s volume was available to evaluate cerebral perfusion changes. Periprocedural perfusion improvement was found in 77 patients (72.0%) and non-improvement in 30 patients (28.0%). Nine patients (8.4%) suffered from recurrent stroke in 180-day follow-up. In Cox proportional hazards analysis adjusted for age and sex, perfusion non-improvement was associated with recurrent stroke [hazards ratio (HR): 4.472; 95% CI: 1.069-18.718; p = 0.040]. Conclusion: In patients with symptomatic ICAS treated with endovascular treatment, recurrent stroke may be related to periprocedural cerebral perfusion non-improvement. Registration: http://www.chictr.org.cn. Unique identifier: ChiCTR2100052925.

Collateral Flow in Magnetic Resonance Angiography: Prognostic Value for Vertebrobasilar Stenosis With Stroke Recurrence.

BACKGROUND AND PURPOSE: Intracranial vertebrobasilar atherosclerotic stenosis (IVBAS) is a major cause of posterior circulation stroke. Some patients suffer from stroke recurrence despite receiving medical treatment. This study aimed to determine the prognostic value of a new score for the posterior communicating artery and the P1 segment of the posterior cerebral artery (PCoA-P1) for predicting stroke recurrence in IVBAS. METHODS: We retrospectively enrolled patients with severe IVBAS (70%-99%). According to the number of stroke recurrences, patients were divided into no-recurrence, single-recurrence, and multiple-recurrences groups. We developed a new 5-point grading scale, with the PCoA-P1 score ranging from 0 to 4 based on magnetic resonance angiography, in which primary collaterals were dichotomized into good (2-4 points) and poor (0 or 1 point). Stroke recurrences after the index stroke were recorded. Patients who did not experience stroke recurrence were compared with those who experienced single or multiple stroke recurrences. RESULTS: From January 2012 to December 2019, 176 patients were enrolled, of which 116 (65.9%) had no stroke recurrence, 35 (19.9%) had a single stroke recurrence, and 25 (14.2%) had multiple stroke recurrences. Patients with single stroke recurrence (odds ratio [OR]=4.134, 95% confidence interval [CI]=1.822-9.380, p=0.001) and multiple stroke recurrences (OR=6.894, 95% CI=2.489-19.092, p<0.001) were more likely to have poor primary collaterals than those with no stroke recurrence. CONCLUSIONS: The new PCoA-P1 score appears to provide improve predictions of stroke recurrence in patients with IVBAS.

Association of residual stenosis after balloon angioplasty with vessel wall geometries in intracranial atherosclerosis.

BACKGROUND: Percutaneous transluminal balloon angioplasty (PTBA) may be an alternative treatment for patients with symptomatic intracranial atherosclerotic disease (ICAD) refractory to medical treatment. This study aimed to investigate the association of vessel wall geometric characteristics on high-resolution magnetic resonance vessel wall imaging (MR-VWI) with low residual stenosis in patients with ICAD after PTBA. METHODS: Patients with symptomatic ICAD who underwent PTBA were prospectively and consecutively enrolled. High-resolution MR-VWI was performed before the PTBA. Vessel wall geometries of the target artery, including normalized wall index (NWI: wall area/vessel area × 100%), normalized wall thickness index (NWTI: mean wall thickness/vessel radius × 100%), and remodeling index (RI) were evaluated. Low residual stenosis was defined as postprocedural stenosis degree ≤50%. Perioperative complications including symptomatic ischemic stroke/intracranial hemorrhage, death, and arterial dissection were recorded. The baseline characteristics, vessel wall geometries, and perioperative complications were compared between the patients with low residual stenosis and high residual stenosis. RESULTS: Among 60 patients prospectively enrolled, low residual stenosis was achieved in 46 participants (77%). Three patients (5%) suffered from symptomatic ischemic stroke within 30 days. Multivariable logistic regression showed that a lower NWI and lower NWTI were associated with low residual stenosis after PTBA (adjusted OR 0.57, 95% CI 0.35 to 0.94, p=0.027; and adjusted OR 0.88, 95% CI 0.80 to 0.98, p=0.015). CONCLUSIONS: Lower NWI and NWTI of the target artery on high-resolution MR-VWI were associated with low residual stenosis in patients with ICAD after PTBA.

High-resolution magnetic resonance vessel wall imaging-guided endovascular recanalization for nonacute intracranial artery occlusion.

OBJECTIVE: On the basis of the characteristics of occluded segments on high-resolution magnetic resonance vessel wall imaging (MR-VWI), the authors evaluated the role of high-resolution MR-VWI-guided endovascular recanalization for patients with symptomatic nonacute intracranial artery occlusion (ICAO). METHODS: Consecutive patients with symptomatic nonacute ICAO that was refractory to aggressive medical treatment were prospectively enrolled and underwent endovascular recanalization. High-resolution MR-VWI was performed before the recanalization intervention. The characteristics of the occluded segments on MR-VWI, including signal intensity, occlusion morphology, occlusion angle, and occlusion length, were evaluated. Technical success was defined as arterial recanalization with modified Thrombolysis in Cerebral Infarction grade 2b or 3 and residual stenosis < 50%. Perioperative complications were recorded. The characteristics of the occluded segments on MR-VWI were compared between the recanalized group and the failure group. RESULTS: Twenty-five patients with symptomatic nonacute ICAO that was refractory to aggressive medical treatment were consecutively enrolled from April 2020 to February 2021. Technical success was achieved in 19 patients (76.0%). One patient (4.0%) had a nondisabling ischemic stroke during the perioperative period. Multivariable logistic analysis showed that successful recanalization of nonacute ICAO was associated with occlusion with residual lumen (OR 0.057, 95% CI 0.004-0.735, p = 0.028) and shorter occlusion length (OR 0.853, 95% CI 0.737-0.989, p = 0.035). CONCLUSIONS: The high-resolution MR-VWI modality could be used to guide endovascular recanalization for nonacute ICAO. Occlusion with residual lumen and shorter occlusion length on high-resolution MR-VWI were identified as predictors of technical success of endovascular recanalization for nonacute ICAO.

Intraplaque Enhancement Is Associated With Artery-to-Artery Embolism in Symptomatic Vertebrobasilar Atherosclerotic Diseases.

Objective: There are limited data regarding the characteristics of intracranial plaques according to stroke mechanism in the posterior circulation. This study aims to compare whether the plaque characteristics and baseline features are different in patients with artery-to-artery (A-to-A) embolism and those with parent artery disease in the intracranial vertebrobasilar atherosclerotic disease. Methods: From September 2014 to January 2017, patients with recent posterior circulation stroke due to intracranial vertebrobasilar atherosclerotic disease were retrospectively analyzed. Patients with the following eligibility criteria were included: (1) age ≥18 years old, (2) ischemic stroke in the vertebrobasilar territory, (3) 70-99% stenosis of the intracranial vertebral artery or basilar artery, and (4) two or more atherosclerotic risk factors. Patients with concomitant ipsilateral or bilateral extracranial vertebral artery >50% stenosis, cardio-embolism, or non-atherosclerotic stenosis were excluded. The plaque characteristics, including intraplaque compositions (intraplaque hemorrhage and intraplaque calcification), intraplaque enhancement, and remodeling index, were evaluated by using 3T high-resolution magnetic resonance imaging (HRMRI). The baseline features including vascular risk factors and the involved artery were collected. Patients were divided into A-to-A embolism and parent artery disease groups based on the diffusion-weighted images, T2-weighted images, or computed tomography. The plaque characteristics and baseline features were compared between the two groups. Results: Among consecutive 298 patients, 51 patients were included. Twenty-nine patients had A-to-A embolism and 22 patients had parent artery disease. Compared with parent artery disease, the occurrence rates of intraplaque enhancement and intracranial vertebral involvement were higher in the A-to-A embolism group (79.3 vs. 36.4%; p = 0.002 and 62.1 vs. 18.2%; p = 0.002, respectively). Multivariable logistic regression analysis showed that intraplaque enhancement and intracranial vertebral artery plaques were also associated with A-to-A embolism (adjusted OR, 7.31; 95% CI 1.58-33.77; p = 0.011 and adjusted OR, 9.42; 95% CI 1.91-46.50; p = 0.006, respectively). Conclusion: Intraplaque enhancement and intracranial vertebral artery plaques seem to be more closely associated with A-to-A embolism than parent artery disease in patients with symptomatic intracranial vertebrobasilar disease. Clinical Trial Registration:http://www.clinicaltrials.gov, identifier: NCT02705599.

Intracranial collaterals and arterial wall features in severe symptomatic vertebrobasilar stenosis.

BACKGROUND AND AIMS: The protective role of intracranial primary collaterals on plaque vulnerability is not well established. We aimed to explore the association of intracranial collateral status with arterial wall features including arterial remodeling and culprit plaque features in severe symptomatic intracranial vertebrobasilar atherosclerosis (sIVBAS). METHODS: Posterior circulation stroke or TIA patients owing to sIVBAS from a three-dimensional high-resolution MRI (3D HRMRI) prospective observational study was included for current analysis. Participants were dichotomized into poor and good collateral groups according to a modified semiquantitative grading system for primary collateral of posterior circulation. Differences of arterial remodeling, culprit plaque distribution, enhancement, intraplaque hemorrhage (IPH), and calcification on HRMRI were compared between the two groups. RESULTS: Seventy-four eligible patients were included, wherein 39 in poor collateral group and 35 in good collateral group. The average age was 57.0 ± 9.0 years, 65 (87.8%) were male, 62 (83.8%) were diagnosed with ischemic stroke and 12 (16.2%) with TIA. Patients with good collateral had lower occurrence of arterial positive remodeling and plaque diffuse distribution, enhancement (Adjusted OR = 0.17 [0.05-0.54], p < 0.01; adjusted OR = 0.26 [0.06-0.99], p = 0.05; adjusted OR = 0.17 [0.03-0.96], p = 0.04, respectively). No significant differences on IPH and calcification were found between poor and good collateral group (p > 0.05). CONCLUSION: Intracranial good collateral of posterior circulation may be associated with lower risk of arterial positive remodeling and culprit plaque diffuse distribution, plaque enhancement in patients with severe sIVBAS. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT02705599.

Different risk factors in identical features of intracranial atherosclerosis plaques in the posterior and anterior circulation in high-resolution MRI.

BACKGROUND: We constructed a high-volume registry to identify whether risk factors of intracranial atherosclerotic plaque (ICAP) features differ in the posterior and anterior circulation in patients with symptomatic intracranial atherosclerotic stenosis (ICAS) investigated by high-resolution magnetic resonance imaging (HRMRI). METHODS: The registry was constructed for patients with symptomatic ICAS who underwent HRMRI for culprit plaques. ICAP-vulnerable features included positive remodelling, diffuse distribution, intraplaque haemorrhage and strong enhancement. RESULTS: We analysed risk factors for the same ICAP features between the posterior and anterior circulation in data of 97 patients in the posterior circulation and 105 patients in the anterior circulation ICAPs. In patients with diffuse distribution, the probability of being female were lower [odds ratio (OR):0.08; 95% confidence interval (CI):0.02-0.34; p = 0.001] and having diabetes mellitus was higher (OR: 7.75; 95% CI:1.75-34.39; p = 0.007) in posterior circulation patients. In patients with strong enhancement, the probability of having diabetes was higher in posterior circulation patients (OR:6.71; 95% CI:1.37-32.81; p = 0.019). CONCLUSIONS: Our results demonstrate more risk factors in the posterior than in the anterior circulation in patients with the same ICAP-vulnerable features, highlighting the need for stratification of risk factors in symptomatic ICAPs. TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT02705599.