Intracranial Artery Atherosclerosis Research Articles

Carotid atherosclerotic plaque predicts progression of intracranial artery atherosclerosis: A MR imaging-based community cohort study

PurposeIntracranial artery atherosclerosis (ICAS) progression is associated with stroke. However, the association of carotid plaque with ICAS progression among stroke-free participants is still unclear. This study aimed to evaluate the association between carotid plaque and ICAS progression in stroke-free participants. MethodStroke-free participants were recruited from a community-based cohort study. All participants underwent questionnaire interviews, blood tests, and high-resolution vessel wall magnetic resonance (MR) imaging at baseline and follow-up for around three years. The atherosclerotic plaque was defined as eccentric wall thickening on MR imaging. The presence, location, total number, and burden (maximum wall thickness, length, and stenosis) of carotid and intracranial plaque were evaluated. ICAS progression was defined as the number increased or plaque burden (maximum wall thickness, length, or stenosis increase) increased by ≥ 20 %. The association between carotid plaque and ICAS progression was evaluated using multivariable logistic regression. ResultsOf the 312 participants (mean age at baseline: 59.85 ± 13.04 years; 136 males) who completed baseline and follow-up studies with a mean time interval of 3.15 ± 0.59 years, 85 (27.24 %) had progression of ICAS during follow-up. At least one carotid plaque was detected at baseline in 167 (53.53 %) participants. In the multivariable logistic analysis, carotid plaque was a significant predictor for the progression of ICAS (odds ratio, 2.04; 95 % confidence interval, 1.06–3.92; P = 0.032). ConclusionsCarotid plaque is associated with intracranial artery atherosclerosis progression in stroke-free population. Our findings suggest that carotid plaque may be an effective predictor for intracranial artery atherosclerosis progression.

Carotid Siphon Calcification Predicts the Symptomatic Progression in Branch Artery Disease With Intracranial Artery Stenosis-Brief Report.

Background:Arterial calcification in the aortic arch, carotid bifurcation, or siphon on computed tomography was associated with cardiovascular disease. The association between arterial calcification prevalence and progression of branch atheromatous disease (BAD) in intracranial artery atherosclerosis was little investigated.Methods:This study included 310 patients with ischemic stroke from one stroke center. Patients were divided into BAD (110) and non-BAD groups (200). Baseline characteristics, lipids, and arterial calcification were measured. The primary outcome was the prevalence of arterial calcification in BAD progression, and the secondary outcome was the prevalence of calcification in arterial stenosis. The association or correlation among calcification prevalence, lipid markers, and BAD progression was analyzed using logistic regression, receiver operating characteristic curve, and linear regression.Results:Our study found that carotid siphon calcification on computed angiography was more prevalent (P=0.01) in patients with BAD and also more prevalent (P<0.001) in intracranial artery stenosis, and its computed tomography values could independently predict the symptomatic progression (P=0.01). Furthermore, a strong linear correlation between oxidized lipid and calcification density was found (beta=−0.73, P=0.0048) in patients with BAD, a subtype (B-type) of intracranial arterial atherosclerotic disease.Conclusions:We found that carotid siphon calcification was associated with BAD and its computed tomography values could predict the symptomatic progression in patients with intracranial arterial atherosclerotic disease and BAD, indicating the important role of carotid calcification in B-type intracranial arterial atherosclerotic disease.Registration:URL: http://www.chictr.org.cn; Unique identifier: ChiCTR1800018315

A comparison between different endovascular treatment strategies for acute large vessel occlusion due to intracranial artery atherosclerosis: data fromANGEL-ACT Registry.

The aim of our study is to compare the characteristics and clinical outcomes among the different endovascular treatment (EVT) strategies for large vessel occlusion underlying intracranial atherosclerosis (ICAS-LVO) in a recent nationwide registry. Patients with isolated ICAS-LVO were enrolled in our analysis and were categorized into three groups: first-line mechanical thrombectomy (MT) with rescue angioplasty and/or stenting (MT + RS), direct angioplasty and/or stenting without thrombectomy (DA), and MT alone. Baseline and periprocedural characteristics, successful recanalization, and 90-day functional outcomes were compared. Of 396 patients with isolated ICAS-LVO in our study, successful recanalization was achieved in 94.5%, 100%, and 90.9% of patients in the MT + RS, DA, and MT groups, respectively. The 90-day functional independence in the three groups was 50.8%, 59.0%, and 45.1%. The main efficacy and safety outcomes showed no significant differences among the groups. First-pass recanalization (FPR) was more observed in the MT group (43.4%), the recanalization rate per attempt in the MT group gradually decreased until the fourth attempt, and further maneuvers showed recanalization rates of ≈0% per attempt. MT + RS (adjusted odds ratio [aOR] 0.10, p < 0.0001) and DA (aOR 0.18, p = 0.0013) were associated with lower FPR rate than MT alone in the multivariable logistic regression. The technical feasibility and favorable outcomes of several EVT strategies for ICAS-LVO were established in our study. First-line MT with a bailout angioplasty is a reasonable option for ICAS-LVO, and DA is an effective option for the cases when ICAS-LVO is strongly suspected before EVT procedure.

Development and validation of visual grading system for stenosis in intracranial atherosclerotic disease on time-of-flight magnetic resonance angiography.

Although the overestimation problem of time-of-flight magnetic resonance angiography (TOF-MRA) applying the warfarin-aspirin symptomatic intracranial disease (WASID) method to assess intracranial arterial stenosis has often been suggested, no pertinent grading system for TOF-MRA has been developed. We aimed to develop and evaluate the performance of a visual grading system for intracranial arterial stenosis on TOF-MRA (MRAVICAST). This single-center cohort study analyzed prospective observational registry data from a comprehensive stroke center between January 2014 and February 2020. Patients with confirmed stenosis of the intracranial large arteries who underwent confirmative digital subtraction angiography (DSA) were included; a 4-point grading system was developed based on physical characteristics of TOF-MRA. The overall diagnostic accuracies of MRAVICAST for each grade, interobserver reproducibility, and positive predictive values for > 50% and > 70% stenoses were evaluated. We analyzed 132 segments with intracranial atherosclerotic stenosis from 71 patients (34 men and 37 women; mean age, 61.0 ± 15.25years; range, 21-89years). The overall diagnostic accuracy of MRAVICAST (93.9%, 124/132) was higher than that of MRAWASID (50.8%, 67/132) for each grade. The degree of stenosis did not differ significantly between MRAVICAST and DSAWASID (p = .849). Regarding reproducibility, MRAVICAST demonstrated excellent interobserver agreement (ICC, 0.989; 95% CI, 0.979-0.999). The positive predictive values of MRAVICAST for the diagnosis of > 50% and > 70% stenoses were 97.3% and 100.0%, respectively. The new intuitive grading system accurately and reliably determined the degree of stenosis in intracranial arterial atherosclerosis patients. MRAVICAST could be a versatile alternative to MRAWASID for evaluating intracranial arterial stenosis. • In this retrospective diagnostic study (sample: 132 stenotic segments), the overall accuracy of the visual grading system (MRAVICAST) was 94%, and positive predictive value for > 50% stenosis was 97%. • In the era of medical treatment for intracranial atherosclerotic stenosis, MRAVICAST could be a versatile alternative method to MRAWASID for evaluating intracranial arterial stenosis.

Atherogenic Dyslipidemia and Residual Vascular Risk After Stroke or Transient Ischemic Attack.

Notwithstanding the current guideline-based management, patients with stroke retain a substantial risk of further vascular events. We aimed to assess the contribution of atherogenic dyslipidemia (AD) to this residual risk. This was a prospective observational study, in which 792 patients (mean age, 70.1 years; male, 60.2%) with acute ischemic stroke (n=710) or transient ischemic attack (n=82) within 1 week of onset were consecutively enrolled and followed for 1 year. AD was defined as having both elevated levels of triglycerides ≥150 mg/dL and low HDL-C (high-density lipoprotein cholesterol) <40 mg/dL in men or <50 mg/dL in women, under fasting conditions. The primary outcome was a composite of major adverse cardiovascular events, including nonfatal stroke, nonfatal acute coronary syndrome, and vascular death. The prevalence of AD was 12.2%. Patients with AD more often had intracranial artery stenosis than those without (42.3% versus 24.1%; P=0.004), whereas no differences were observed in the prevalence of extracranial artery stenosis (17.7% versus 12.9%; P=0.62) or aortic plaques (33.3% versus 27.0%; P=0.87). At 1 year, patients with AD were at a greater risk of major adverse cardiovascular events (annual rate, 24.5% versus 10.6%; hazard ratio [95% CI], 2.33 [1.44-3.80]) and ischemic stroke (annual rate, 16.8% versus 8.6%; hazard ratio [95% CI], 1.84 [1.04-3.26]) than those without AD. When patients were stratified according to baseline LDL-C (low-density lipoprotein cholesterol) level, AD was predictive of major adverse cardiovascular events among those with LDL-C ≥100 mg/dL (n=509; annual rate, 20.5% versus 9.6%; P=0.036) as well as those with LDL-C <100 mg/dL (n=283; annual rate, 38.6% versus 12.4%; P<0.001). AD is associated with intracranial artery atherosclerosis and a high residual vascular risk after a stroke or transient ischemic attack. AD should be a promising modifiable target for secondary stroke prevention. Registration: URL: https://upload.umin.ac.jp; Unique identifier: UMIN000031913.

Effects of Pemafibrate in Patients with Stroke and Hypertriglyceridemia: Baseline Cerebral Artery Diseases and 3-Month Laboratory Outcomes.

Aims: The role of hypertriglyceridemia in stroke is poorly understood. The Pemafibrate for Prevention of Atherosclerotic Diseases in Stroke (PPAR Stroke) study was designed to assess the effects of a novel selective peroxisome proliferator-activated receptor alpha modulator, pemafibrate, on vascular outcomes in stroke patients with hypertriglyceridemia. Methods: This was a prospective single-arm study including 74 patients (mean age, 64.1 years; male 75.7%) with stroke and hypertriglyceridemia (defined as fasting serum triglycerides levels of ≥ 150 mg/dL) who were treated with pemafibrate at 0.2 mg or 0.1 mg/day. The present report assessed the association of hypertriglyceridemia with cerebral large and small vessel diseases at baseline and changes in laboratory parameters after a three-month pemafibrate therapy. Results: Patients with triglycerides levels of ≥ 227 mg/dL (higher than the median) more often presented with intracranial artery atherosclerotic stenosis than those with triglycerides levels of 150–227 mg/dL (44.4% vs. 21.6%,p=0.037). On the other hand, no differences were found in the prevalence of extracranial artery atherosclerosis and cerebral small vessel diseases. Mean triglycerides levels were significantly reduced from 285 mg/dL at baseline to 175 mg/dL at 3 months (p＜0.001). High-density lipoprotein cholesterol levels increased from 48 mg/dL to 53 mg/dL (p＜0.001). In addition, significant reductions in alanine aminotransferase, γ-glutamyl transpeptidase, and interleukin-6 levels were observed (p＜0.001,p=0.002, andp=0.044, respectively). Conclusions: Higher triglycerides levels are associated with intracranial artery atherosclerosis. Pemafibrate showed pleiotropic effects not only in ameliorating atherogenic dyslipidemia but also in the reduction of the levels of inflammatory markers and hepatobiliary enzymes.

Association of Type 2 Diabetes Mellitus and Glycemic Control With Intracranial Plaque Characteristics in Patients With Acute Ischemic Stroke.

Type 2 diabetes mellitus (T2DM) has shown to be associated with carotid plaque vulnerability. However, the impact of T2DM on intracranial artery atherosclerosis is not well-understood. To evaluate the association of diabetes and glycemic control with intracranial atherosclerotic plaque characteristics identified by three-dimensional contrast enhanced MR vessel wall imaging in patients after acute ischemic stroke. Prospective. Two hundred and eighty-eight symptomatic patients with acute ischemic stroke due to intracranial atherosclerotic plaque. T1 WI volume isotropic turbo spin-echo acquisition sequence at 3.0 T. Clinical profiles, blood biomarkers, the number of intracranial plaques, plaque enhanced score, and the features (location, luminal stenotic rate, intraplaque hemorrhage, length, burden, enhancement grade, and ratio) of culprit plaque (defined as the most stenotic lesion ipsilateral to the ischemic event) and nonculprit plaque were analyzed by three radiologists. Analysis of variance (ANOVA), Shapiro-Wilk normality test, Levene's test, ANOVA with Bonferroni post-hoc test, Kruskal Wallis H test with subsequent pairwise comparisons, chi-square with Bonferroni post-hoc test, generalized linear regression, Pearson correlation test, Kendall's W and intra-class correlation coefficient. Two hundred and twenty-five participants (age 60 ± 10 years, 58.7% male) with 958 intracranial plaques were included. More intracranial plaques were found in the T2DM group than the non-T2DM group (4.80 ± 2.22 vs. 3.60 ± 1.78, P < 0.05). Patients with poorly-controlled T2DM exhibited higher culprit plaque enhancement ratio than patients with well-controlled T2DM and non-T2DM (2.32 ± 0.61 vs. 1.60 ± 0.62 and 1.39 ± 0.39; respectively, P < 0.05). After adjusting for other clinical variables, T2DM was independently associated with increased intracranial plaque number (β=0.269, P < 0.05), and HbA1c level was independently associated with culprit plaque enhancement ratio (β=0.641, P < 0.05) in multivariate analysis. T2DM is associated with an increased intracranial plaque number. Higher HbA1c is associated with stronger plaque enhancement. 3D contrast enhanced MR vessel wall imaging may help better understand the association of T2DM and glycemic control with intracranial plaque. 1 TECHNICAL EFFICACY STAGE: 3.

Comparison of plaque characteristics of small and large subcortical infarctions in the middle cerebral artery territory using high-resolution magnetic resonance vessel wall imaging

The characteristics of plaque that ultimately lead to different subcortical infarctions remain unclear. We explored the differences in plaque characteristics between patients with small subcortical infarction (SSI) and large subcortical infarction (LSI) of the middle cerebral artery (MCA) using high-resolution magnetic resonance vessel wall imaging (HR-MRVWI). The study group comprised 71 patients (mean age, 47.49±11.5 years; 55 male) with MCA territory ischemic stroke. Whole-brain HR-MRVWI was performed using a three-dimensional T1-weighted variable-flip-angle turbo spin echo (SPACE) sequence. Patients were divided into SSI and LSI groups based on routine MRI images. Plaque distribution was classified as the superior, inferior, ventral, or dorsal wall of the MCA. The number of quadrants with plaque formation, location of plaque, plaque burden (PB), arterial remodeling pattern (positive or negative), and degree of stenosis were analyzed and compared between groups. Of the 71 patients, 43 (60.6%) and 28 (39.4%) were identified as the SSI and LSI groups, respectively. The proportion of plaques involving only one quadrant was significantly higher in the SSI group, and these plaques were located in the superior or dorsal MCA vessel wall. There was no significant difference between groups in the proportion of plaques involving two or more quadrants, plaque distribution, or PB. Most plaques in both groups showed positive remodeling, and the percentage of remodeling pattern was similar. A significantly higher incidence of low-grade stenosis (<50%) was observed in the SSI group. Both SSI and LSI may be associated with major intracranial artery atherosclerosis, but patients with SSI showed relatively fewer quadrants with plaque formation and a lesser degree of stenosis.

Prevalence, clinical characteristics and prognosis of intracranial artery atherosclerosis in heterozygous familial hypercholesterolemia: insights from magnetic resonance angiography imaging analysis

Abstract Introduction Heterozygous familial hypercholesterolemia (HeFH) exhibits substantially atherogenic substrate which involves coronary and peripheral arteries. Whether atherosclerosis in HeFH propagates to intracranial arteries causing stroke remains to be determined. Purpose To characterize intracranial artery stenosis (IAS) in subjects with HeFH. Methods 148 HeFH subjects who underwent MRI/MRA imaging to evaluate intracranial arteries were analyzed. IAS was defined as the presence of stenosis with its % diameter stenosis ≥25%. Clinical demographics and cardiovascular events (all-cause death, ACS, stroke and PAD) were compared in those with and without IAS. Results IAS was observed in 24.3% (=36/148) of study subjects. It was more frequently located at middle cerebral artery (30.6%=11/36), followed by internal carotid artery (25.0%=9/36). 47.2% of IAS exhibited % diameter stenosis ≥75%. Furthermore, 58.3% of HeFH patients with IAS exhibited concomitance of CAD, PAD or carotid stenosis. They were more likely to be older (Table). While there was no significant difference in LDL-C level, an elevated triglyceride level was observed in those with IAS (Table). Of note, during the observational period (median=14.1 years), IAS was associated with a greater likelihood of experiencing not only stroke but other cardiovascular events (all-cause death + ACS + PAD) (picture). Multivariate analysis demonstrated triglyceride level ≥1.7mmol/l as an independent predictor of IAS in HeFH patients (HR=5.53, 95% CI: 1.85–16.5, p=0.002). Conclusions Around one-fourth of HeFH patients harboured IAS, which was associated with concomitance of atherosclerosis in other vascular beds and the occurrence of stroke and other cardiovascular events. Given the relationship of IAS with hypertriglyceridemia, this lipid feature may be an important contributor to atherosclerotic formation which involves intracranial artery in HeFH patients. Clinical outcome Funding Acknowledgement Type of funding source: None

Are Genetic Variants Associated with the Location of Cerebral Arterial Lesions in Stroke Patients?

Background: Genetic variants may play a role in determining the location of cerebral atherosclerosis. We aimed to investigate the association between RNF213, MMP2, and genetic polymorphisms linked to vascular tortuosity with the location of cerebral arterial atherosclerosis. Methods: A prospective case-control study was conducted on patients with ischemic stroke and age- and sex-matched stroke-free controls. The stroke patients were categorized into those with intracranial artery atherosclerosis (ICAS), extracranial artery atherosclerosis (ECAS), and small vessel occlusion (SVO). Six single nucleotide polymorphisms (SNPs) including rs2118181 (FBN1), rs2179357 (SLC2A10), rs1036095 (TGFBR2), rs243865 (MMP2), rs1800470 (TGFB1), and rs112735431 (RNF213) were analyzed with the TaqMan Genotyping Assay, and the distribution of genotypes across groups was compared. Results: None of the 6 SNPs were associated with stroke on comparing the 449 stroke patients (71 with ECAS, 169 with ICAS, and 209 with SVO) to the 447 controls. In the subgroup analysis, the adjusted odds ratios (aORs) for age and sex indicated a significant association between rs112735431 and ICAS in the allele comparison analysis and in the additive and dominant model analyses. rs112735431 was associated with anterior circulation involvement and increased burden of cerebral atherosclerosis. rs2179357 was significantly associated with ICAS in the recessive model analysis, and rs1800470 was significantly associated with ECAS in the recessive model analysis when compared to controls. Conclusion: rs112735431 was associated with ICAS and increased atherosclerosis burden in Korean stroke patients. Further studies are needed to elucidate the role of rs112735431 and to confirm the association of rs2179357 and rs1800470 with cerebral atherosclerosis.

Abstract TP181: Are Genetic Variants Associated With the Location of Cerebral Arterial Lesions in Stroke Patients?

Introduction: Genetic variants may play a role in determining the location of cerebral atherosclerosis. Hypothesis and aim: We aimed to investigate the association between RNF213 , MMP2 , and genetic polymorphisms linked to vascular tortuosity with the location of cerebral arterial atherosclerosis. Methods: A prospective case-control study was conducted on patients with ischemic stroke and age- and sex-matched stroke-free controls. The stroke patients were categorized into those with intracranial artery atherosclerosis (ICAS), extracranial artery atherosclerosis (ECAS), and small vessel occlusion (SVO). Six single nucleotide polymorphisms (SNPs) including rs2118181 ( FBN1 ), rs2179357 ( SLC2A10 ), rs1036095 ( TGFBR2 ), rs243865 ( MMP2 ), rs1800470 ( TGFB1 ), and rs112735431 ( RNF213 ) were analyzed with the TaqMan Genotyping Assay, and the distribution of genotypes across groups was compared. Results: None of the six SNPs were associated with stroke on comparing the 449 stroke patients (71 with ECAS, 169 with ICAS, and 209 with SVO) to the 447 controls. In the subgroup analysis, the adjusted odds ratios (aORs) for age and sex indicated a significant association between rs112735431 and ICAS in the allele comparison analysis and in the additive and dominant model analyses. rs112735431was associated with anterior circulation involvement and increased burden of cerebral atherosclerosis. rs2179357 was significantly associated with ICAS in the recessive model analysis, and rs1800470 was significantly associated with ECAS in the recessive model analysis when compared to controls. Conclusion: rs112735431 was associated with ICAS, and increased atherosclerosis burden in the Korean population. Further studies are needed to elucidate the role of rs112735431, and to confirm the association of rs2179357 and rs1800470 with cerebral atherosclerosis.

Association of severity between carotid and intracranial artery atherosclerosis.

ObjectiveThis study sought to investigate the relationship of atherosclerosis between intracranial and extracranial carotid arteries using three‐dimensional multicontrast magnetic resonance (MR) vessel wall imaging.MethodsPatients with recent cerebrovascular symptoms in anterior circulation were recruited and underwent MR vessel wall imaging for intracranial and extracranial carotid arteries. The plaque burden, including maximum wall thickness (Max WT) and stenosis, and presence of intraplaque hemorrhage (IPH) were assessed. The correlation of the plaque characteristics between intracranial and extracranial carotid arteries was determined.ResultsIn total, 107 patients (mean age: 57.0 ± 11.1 years, 69 males) were recruited. In discriminating intracranial severe stenosis (≥50% stenosis), the odds ratio (OR) of Max WT of extracranial carotid arteries was 1.41 (95% confidence interval [CI], 0.94–2.11, P = 0.095) and 1.72 (95% CI, 1.04–2.83, P = 0.034) before and after adjusting for confounding factors, respectively. The OR of stenosis of extracranial carotid arteries with increment of 10% was 1.26 (95% CI, 0.99–1.60, P = 0.054) and 1.37 (95% CI, 1.03–1.82, P = 0.033) before and after adjusting for confounding factors, in discriminating intracranial severe stenosis respectively. Receiver operating characteristic analysis revealed that the area under the curve (AUC) of Max WT, stenosis, and IPH of extracranial carotid artery plaques was 0.641, 0.605, and 0.603 in discriminating intracranial severe stenosis, respectively. After adjusting for confounding factors, the AUC of Max WT, stenosis, and presence of IPH in extracranial carotid artery plaques increased to 0.812, 0.817 and 0.781, respectively.InterpretationCarotid artery plaque burden is significantly associated with severe intracranial artery stenosis, suggesting that extracranial carotid plaque burden might be an independent indicator for severity of intracranial artery atherosclerosis.

The Protective Effect of Middle Cerebral Artery Calcification on Symptomatic Middle Cerebral Artery Infarction.

The presence of intracranial artery calcification is associated with an increased risk for stroke. However, calcified atherosclerotic plaques are also known to be less vulnerable to rupture. Given this discrepancy, we investigated whether the vulnerability of intracranial arterial atherosclerosis differed based on the presence or absence of calcification. We considered consecutive patients with acute stroke in the unilateral middle cerebral artery (MCA) territory. Patients with any stenotic MCAs were included in this study. Symptomatic MCA was defined as the occurrence of infarctions relevant to the stenotic MCA. The presence of calcification in the MCA was evaluated on noncontrast thin-section computed tomography images using a 3dimensional software package. Generalized estimating equations were used to compare the frequency of calcification between symptomatic and asymptomatic stenosis. Of the 1066 MCAs examined in 533 patients, 645 MCAs were stenotic and were included in the study. Among the 645 stenotic MCAs, 406 MCAs (62.9%) were symptomatic. Calcification was observed in 36 MCAs (5.6%). Calcification in the MCA was more frequently observed in the asymptomatic group (7.9% versus 4.2%; P=0.032). On multivariable analysis, the presence of calcification in MCA atherosclerosis was less frequent in the symptomatic group (odds ratio, 0.46; 95% confidence interval, 0.23-0.92; P=0.027). This study showed that calcified atherosclerosis in the MCA was less frequently symptomatic.

Abstract TP47: Intracranial Intraplaque Hemorrhage in Acute Stroke: Interim Results of the Stroke Imaging Package Study

Introdution: Intracranial artery atherosclerosis is an important cause of ischemic stroke, especially in people of Asian origin. Intraplaque hemorrhage is supposed to be a predictor of ischemic event. The goal of this study was to examine the occurrence of intraplaque hemorrhage in a large cohort of Chinese patients with acute ischemic stroke. Methods: Patients with first ever stroke within 72 hours from onset, confirmed by diffusion weighted imaging, were recruited from 16 medical centers. Conventional MRI, magnetic resonance angiography, HRMRI (including 3-dimentional T1 images and 2-dimentional T2 images), and SWI were performed. Intraplaque hemorrhage was identified if hyperintense signals on 3-dimentional T1 images of HRMRI were observed within intracranial plaques. Results: Six hundred and one patients (70% male, mean age 61±16 years old, mean NIHSS 6± 5) were enrolled. Median time from symptom onset to MRI was 44 ± 20 hours. Of them, 240(40%) were diagnosed with large artery atherosclerosis (LAA) stroke. Intracranial intraplaque hemorrhage was identified in 15 intracranial plaques of 13 patients with LAA stroke. Six plaques with intraplaque hemorrhage were asymptomatic and irrelevant to ischemic infarct lesions. In 2 patients, both symptomatic and asymptomatic intraplaque hemorrhage were observed. Conclusions: The prevalence of intracranial intraplaque hemorrhage was low (5.4%)in acute stroke patients. The clinical importance of asymptomatic intraplaque hemorrhage need further investigations.

In Vivo Validation of Simultaneous Non-Contrast Angiography and intraPlaque Hemorrhage (SNAP) Magnetic Resonance Angiography: An Intracranial Artery Study.

ObjectivesSimultaneous Non-contrast Angiography and intraPlaque hemorrhage (SNAP) technique was recently proposed for joint MRA and intraplaque hemorrhage (IPH) imaging. The purpose of this study is to validate SNAP’s MRA performance in patients with suspected intracranial artery disease.MethodsSNAP and time-of-flight (TOF) techniques with matched field of view and resolution were applied on 15 patients with suspected intracranial artery disease. Both techniques were evaluated based on their detection of luminal stenosis of bilateral middle cerebral arteries (MCA) and the delineation of smallest visible branches (SVB) of the MCA. Statistical analysis was conducted on the artery level.ResultsThe SNAP MRA was found to provide similar stenosis detection performance when compared with TOF (Cohen’s κ 0.79; 95% Confidence Interval: 0.56–0.99). For the SVB comparison, SNAP was found to provide significantly better small artery delineation than TOF (p = 0.017). Inter-reader reproducibility for both measurements on SNAP was over 0.7. SNAP also detected IPH lesions on 13% of the patients.ConclusionsThe SNAP technique’s MRA performance was optimized and compared against TOF for intracranial artery atherosclerosis imaging and was found to provide comparable stenosis detection accuracy. Along with its IPH detection capability, SNAP holds the potential to become a first-line screening tool for high risk intracranial atherosclerosis disease evaluation.

Abstract WP139: Pathological Study of Intracranial Artery Atherosclerosis in 7307 Autopsy Cases

Introduction: It has not been analyzed whether atherosclerotic changes in the major cerebral arteries differ with age or with era of birth. Hypothesis: To examine our hypothesis that such changes would vary with age at death and era of birth, we studied chronological changes in intracranial artery atherosclerosis in consecutive autopsy cases. Methods: We analyzed 7307 autopsy cases of our brain bank from 1972 to 2014. Severity of atherosclerosis was classified on the following semi-quantitative scale based on pathological observation of each artery after formalin fixation: 0 = no stenosis; 0.5 = fatty streaks but no stenosis; 1 = less than 50% stenosis; 2 = 50% to 90% stenosis; 3 = 90% or more stenosis. We scored the cerebral arteries (anterior, middle, and posterior) and vertebral arteries bilaterally and the basilar artery. Then we summed the scores in each patient and defined the sum as the atherosclerosis score. We compared atherosclerosis scores by age at death and era of birth. Results: Atherosclerosis scores increased with age at death, as follows: age 50s, 1.9 ± 3.8; 60s, 4.6 ± 5.2; 70s, 6.1 ± 5.3; 80s, 7.6 ± 5.4; 90s, 8.2 ± 5.3; and 100s, 9.2 ± 5.3 (mean ± SD, P &lt; 0.0001). The percentage of cases with a score of 2 or 3 in each artery also increased with age (P &lt; 0.0001). Interestingly, in each age group (from the 60s to 90s) at the time of death, the score declined as the birth year became later (Figure. P &lt; 0.0001, box plots for each group showing atherosclerosis score). Conclusions: Our analysis from a brain bank cohort showed that intracranial artery atherosclerosis 1) advanced with age, and 2) was more severe in subjects born earlier.

Prevalence of Cerebral Atherosclerosis among Patients with Metabolic Syndrome: A Case Control Study on Egyptian Subjects

Background: The metabolic syndrome (MetS) is a clustering of vascular risk factors that tend to increase the risk of occurrence of diabetes mellitus type 2 (DMT2), cardiovascular and cerebro-vascular ischemic events. The aim of the present study is to investigate the association of extra-cranial and intracranial arterial atherosclerosis as well as silent brain infarction (SBI) with MetS, thereby determining the potential cerebrovascular atherosclerotic risk of MetS in the Egyptian population. Methods: A case control study was conducted on 50 Egyptian subjects with MetS and 30 without with age range from 40 - 60 years old. All participants were free from cerebrovascular ischemic events [stroke or transient ischemic attack (TIA)]. All participants underwent complete neurological examination, assessment of the diagnostic criteria for MetS, carotid and transcranial duplex ultrasonography (U/S) and brain MRI. Results: Preclinical carotid atherosclerosis (athero-sclerotic plaques with <50% stenosis) was associated with MetS (P value = 0.02) that persisted after adjustment for age and other confounders. There was no significant association between increased intima media thickness (IMT) and MetS. There was non-significant association between MetS and intracranial atherosclerotic disease (ICAD) or the degree of intracranial stenosis (ICS). Conversely, there was a highly significant association between MetS and SBI even after adjustment for age and other confounders (P value = 0.001). Conclusion: Metabolic syndrome is an important factor associated with mild to moderate atherosclerosis (<50% stenosis) and silent brain infarcts among asymptomatic individuals. Interventions to reduce MetS are important for prevention of subclinical and clinical cerebral atherosclerotic disease.

Vessel Wall Imaging of the Intracranial and Cervical Carotid Arteries.

Vessel wall imaging can depict the morphologies of atherosclerotic plaques, arterial walls, and surrounding structures in the intracranial and cervical carotid arteries beyond the simple luminal changes that can be observed with traditional luminal evaluation. Differentiating vulnerable from stable plaques and characterizing atherosclerotic plaques are vital parts of the early diagnosis, prevention, and treatment of stroke and the neurological adverse effects of atherosclerosis. Various techniques for vessel wall imaging have been developed and introduced to differentiate and analyze atherosclerotic plaques in the cervical carotid artery. High-resolution magnetic resonance imaging (HR-MRI) is the most important and popular vessel wall imaging technique for directly evaluating the vascular wall and intracranial artery disease. Intracranial artery atherosclerosis, dissection, moyamoya disease, vasculitis, and reversible cerebral vasoconstriction syndrome can also be diagnosed and differentiated by using HR-MRI. Here, we review the radiologic features of intracranial artery disease and cervical carotid artery atherosclerosis on HR-MRI and various other vessel wall imaging techniques (e.g., ultrasound, computed tomography, magnetic resonance, and positron emission tomography-computed tomography).

Vascular tortuosity may be related to intracranial artery atherosclerosis.

Conventional risk factors cannot explain the individual or ethnic difference in the location of cerebral atherosclerosis. Vascular geometry may play a role on this. To investigate the association between the geometrical properties of the middle cerebral artery and intracranial atherosclerosis. Stroke patients with either symptomatic middle cerebral artery or proximal internal carotid artery diseases were enrolled. The diameter, length, and tortuosity (arc-chord ratio, by percent) of the middle cerebral artery was compared between stroke patients and the age- and gender-matched healthy subjects. The geometrical property was also compared between the symptomatic middle cerebral artery and the normal-looking contralateral middle cerebral artery, and between the contralateral middle cerebral arteries in patients with symptomatic middle cerebral artery and proximal internal carotid artery diseases. One hundred seventy-seven patients (101 with middle cerebral artery disease and 76 with proximal internal carotid artery disease) were studied. Symptomatic middle cerebral artery was more tortuous (119·31 ± 16·95 vs. 112·98 ± 14·16; P = 0·009) than the contralateral middle cerebral artery. The contralateral middle cerebral artery of patients with symptomatic middle cerebral artery disease demonstrated a smaller proximal diameter (P = 0·007) and a greater vascular tortuosity than the contralateral middle cerebral artery of patients with proximal internal carotid artery disease (112·01 ± 12·25 vs. 107·46 ± 9·35; P = 0·008) and corresponding middle cerebral artery of healthy control subjects (112·01 ± 12·25 vs. 108·73 ± 9·79; P = 0·04). Young age, female, small diameter, the absence of diabetes, and high tortuosity of the contralateral middle cerebral artery were independently associated with middle cerebral artery atherosclerotic disease. High tortuosity and small diameter are related to middle cerebral artery atherosclerosis, probably by altering hemodynamics. Different degree of tortuosity may be one of the reasons for individual differences in location of cerebral atherosclerosis.

Isolated MCA disease in patients without significant atherosclerotic risk factors: a high-resolution magnetic resonance imaging study.

Diagnosis of intracranial artery atherosclerosis remains often uncertain. The high-resolution magnetic resonance imaging (HR-MRI) enables vessel wall assessment for more precise diagnoses. The aim of the present study was to investigate the etiologies of middle cerebral artery steno-occlusive disease in young adult patients with few atherosclerotic risk factors using HR-MRI. We prospectively studied patients who visited a tertiary hospital in Seoul, Korea, and had (1) unilateral middle cerebral artery disease (≥50% stenosis or occlusion), (2) were ≤55 years old and had no or minimal (≤1) atherosclerotic risk factors. We excluded patients with a confirmed diagnosis of Moyamoya disease, vasculitis, or dissection and those having emboligenic sources. A presumptive diagnosis was made based on HR-MRI findings, and patients were categorized as HR-athero (atherosclerotic disease), HR-MMD (Moyamoya disease), HR-dissection, or HR-vasculitis. Among 95 patients analyzed, 26 (27.4%) had HR-athero who were more often male (P=0.004), smokers (P=0.018), and had focal stenosis (P=0.003) than others.As compared with the HR-athero patients, 29 HR-MMD patients were more often female (P<0.001) and more often had occlusive lesions (P=0.001) and nonfocal stenosis (P<0.001). The 22 HR-dissection patients tended to have hypertension less often, and the 13 HR-vasculitis patients were younger (P=0.004) and tended to have nonfocal stenosis. [corrected]. In our cohort of young patients with minimal risk factors, atherosclerosis seems to be an uncommon pathology of middle cerebral artery stenosis. HR-MRI aids us to make a more reliable diagnosis.