Recent Translational Research Models of Intracranial Atherosclerotic Disease.

Intracranial atherosclerotic disease (ICAD) is a leading cause of ischemic stroke worldwide. However, research on the pathophysiology of ICAD is scarce due to the relative inaccessibility of histology samples and the lack of comprehensive experimental models. As a result, much of the current understanding of ICAD relies on research on extracranial atherosclerosis. This approach is problematic as intracranial and extracranial arteries are anatomically, structurally, physiologically, and metabolically distinct, indicating that intracranial and extracranial atherosclerosis likely develop through different biologic pathways. The current standard of care for ICAD treatment relies predominantly on therapeutics developed to treat extracranial atherosclerosis and is insufficient given the alarmingly high risk of stroke. To provide a definitive treatment for the disease, a deeper understanding of the pathophysiology underlying ICAD is specifically required. True mechanistic understanding of disease pathogenesis is only possible using robust experimental models. In this review, we aim to identify the advantages and limitations of the existing in vivo and in vitro models of ICAD and basic atherosclerotic processes, which may be used to inform better models of ICAD in the future and drive new therapeutic strategies to reduce stroke risk.

Randomized Secondary Prevention Trials in Participants With Symptomatic Intracranial Atherosclerotic Stenosis.

Intracranial atherosclerotic stenosis is a prevalent cause of ischemic stroke worldwide. Its association with silent cerebral infarcts and its contribution to cognitive impairment and dementia emphasize the critical need for disease prevention and effective management strategies. Despite extensive research on secondary stroke prevention treatment over the past several decades, intracranial atherosclerotic stenosis continues to exhibit a notably higher recurrent stroke rate compared with other causes. This review focuses on randomized secondary prevention trials involving antithrombotic therapy, endovascular treatment, open surgical therapy, and remote ischemic conditioning. It aims to provide an insightful overview of the major findings from each trial and their implications for future research efforts.

Hemodynamic Impairment of Blood Pressure and Stroke Mechanisms in Symptomatic Intracranial Atherosclerotic Stenosis.

BACKGROUND: Hemodynamic impairment of blood pressure may play a crucial role in determining the mechanisms of stroke in symptomatic intracranial atherosclerotic stenosis). We aimed to elucidate this issue and assess the impacts of modifications to blood pressure on hemodynamic impairment. METHODS: From the Third China National Stroke Registry III, computed fluid dynamics modeling was performed using the Newton-Krylov-Schwarz method in 339 patients with symptomatic intracranial atherosclerotic stenosis during 2015 to 2018. The major exposures were translesional systolic blood pressure (SBP) drop and poststenotic mean arterial pressure (MAP), and the major study outcomes were cortex-involved infarcts and borderzone-involved infarcts, respectively. Multivariate logistic regression models and the bootstrap resampling method were utilized, adjusting for demographics and medical histories. RESULTS: In all, 184 (54.3%) cortex-involved infarcts and 70 (20.6%) borderzone-involved infarcts were identified. In multivariate logistic model, the upper quartile of SBP drop correlated with increased cortex-involved infarcts (odds ratio, 1.92 [95% CI, 1.03-3.57]; bootstrap analysis odds ratio, 2.07 [95% CI, 1.09-3.93]), and the lower quartile of poststenotic MAP may correlate with increased borderzone-involved infarcts (odds ratio, 2.07 [95% CI, 0.95-4.51]; bootstrap analysis odds ratio, 2.38 [95% CI, 1.04-5.45]). Restricted cubic spline analysis revealed a consistent upward trajectory of the relationship between translesional SBP drop and cortex-involved infarcts, while a downward trajectory between poststenotic MAP and borderzone-involved infarcts. SBP drop correlated with poststenotic MAP negatively (rs=-0.765; P<0.001). In generating hemodynamic impairment, simulating blood pressure modifications suggested that ensuring adequate blood pressure to maintain sufficient poststenotic MAP appears preferable to the reverse approach, due to the prolonged plateau period in the association between the translesional SBP drop and cortex-involved infarcts and the relatively short plateau period characterizing the correlation between poststenotic MAP and borderzone-involved infarcts. CONCLUSIONS: This research elucidates the role of hemodynamic impairment of blood pressure in symptomatic intracranial atherosclerotic stenosis-related stroke mechanisms, underscoring the necessity to conduct hemodynamic assessments when managing blood pressure in symptomatic intracranial atherosclerotic stenosis.

Remote ischemic conditioning improves cerebral hemodynamics in symptomatic intracranial atherosclerosis: A PET/CT-guided randomized controlled study.

Patients with symptomatic intracranial arterial stenosis (sICAS) suffer embarrassed hemodynamic status and acute ischemic stroke (AIS) recurrence. We aimed to assess the efficacy of remote ischemic conditioning (RIC) on improving this status by evaluating cerebral blood flow (CBF) and cerebral glucose metabolism (CGM) via PET/CT. Adult patients with unilateral sICAS in middle cerebral artery and/or intracranial segment of internal carotid artery-related AIS or transient ischemic attack within 6 months prior to randomization were enrolled. Individuals who received intravenous thrombolysis or endovascular treatment, or sICAS caused by cardiac embolism, small vessel occlusion, or other determined causes were excluded. Twenty-three eligible patients were randomly assigned to standard medical treatment (SMT) (n = 10) or RIC group (n = 13). The RIC protocol consisted of 5 cycles, each for 5-min bilateral upper limb ischemia and 5-min reperfusion period, twice a day, with a total duration of 3 months. Ten healthy volunteers were enrolled as healthy control group. We tested CBF and CGM at the rest stage and the methazolamide-induced stress stage. All patients received PET/CT at baseline and three-month followup. Both CBF and CGM in ipsilateral hemisphere of sICAS patients were significantly decreased at the rest stage and the stress stage (p < .05), which were improved by three-month RIC (p < .05). The lesions decreased notably in RIC group compared to SMT group (p < .05). RIC ameliorated the hemodynamic status and glucose metabolism in regions at high risk of infarction, which might improve the resistance capacity towards ischemic load in sICAS patients.

Association between BMI-based metabolic phenotypes and prevalence of intracranial atherosclerotic stenosis: a cross-sectional study.

BACKGROUND: Obesity and metabolic syndrome (MetS) have been acknowledged to commonly co-exist and lead to increased risks of stroke, whereas the association between various BMI-based metabolic phenotypes and development of intracranial atherosclerotic stenosis (ICAS) remained controversial. METHODS: A total of 5355 participants were included from the Asymptomatic Polyvascular Abnormalities Community (APAC) study. Participants were categorized into six groups according to their body mass index (BMI) and MetS status. ICAS was assessed using transcranial Doppler (TCD) Ultrasonography. Logistic regression was employed to evaluate the association between BMI-based metabolic phenotypes and ICAS. RESULTS: 704 participants were diagnosed with ICAS. Compared to the metabolic healthy normal weight (MH-NW) group, the metabolic unhealthy normal weight (MUH-NW) group demonstrated a higher risk of ICAS (full-adjusted odds ratio [OR], 1.91; 95% confidence interval [CI], 1.42-2.57), while no significant association was observed in the metabolic unhealthy obesity (MUO) group (full-adjusted OR, 1.07; 95% CI, 0.70-1.65) and other metabolic healthy groups regardless of BMI. The results were consistent across gender, age, smoking, alcohol intake, and physical activity subgroups. CONCLUSION: The present study suggested that MUH-NW individuals had a significant association with increased risk of ICAS compared with MH-NW individuals.

PSCK9 inhibitors reduced early recurrent stroke in patients with symptomatic intracranial atherosclerotic stenosis.

BACKGROUND: Symptomatic intracranial atherosclerotic stenosis (ICAS) is prone to cause early recurrent stroke (ERS). Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors lower low-density lipoprotein cholesterol (LDL-C) levels and prevent cardiovascular events. This multicentre, hospital-based prospective cohort study was designed to investigate whether PCSK9 inhibitors would prevent ERS in patients with symptomatic ICAS. METHODS: From 1 October 2020 to 30 September 2022, consecutive patients with acute ischaemic stroke attributed to ICAS admitted within 1 week after onset were enrolled and followed up for 1 month. Patients were divided into two groups, the PCSK9 inhibitors group receiving PCSK9 inhibitors add-on therapy, and the control group receiving statins and/or ezetimibe. The primary outcome was ERS. Cox proportional hazard models and Kaplan-Meier survival curve were used to estimate the association between PCSK9 inhibitors and ERS. RESULTS: At the end of follow-up, the LDL-C levels were further lowered by PCSK9 inhibitors add-on therapy (n=232, from 3.06±1.16 mmol/L to 2.12±1.19 mmol/L) than statins and/or ezetimibe treatment (n=429, from 2.91±1.05 mmol/L to 2.64±0.86 mmol/L, p<0.001). The Kaplan-Meier survival curves showed that PCSK9 inhibitors add-on therapy significantly reduced ERS (5.59%, 24/429, vs 2.16%, 5/232; log-rank test, p=0.044). The multivariate Cox regression analysis revealed that, after adjusting for confounders with a p value less than 0.05 in univariate analysis or of particular importance, the HR was 0.335 (95% CI 0.114 to 0.986, p=0.047), compared with the control group. CONCLUSIONS: In our study, PCSK9 inhibitors add-on therapy further reduced LDL-C levels and ERS in patients with symptomatic ICAS.

Plaque Evolution and Vessel Wall Remodeling of Intracranial Arteries: A Prospective, Longitudinal Vessel Wall MRI Study.

BACKGROUND: Progression of intracranial atherosclerotic disease (ICAD) is associated with ischemic stroke events and can be quantified with three-dimensional (3D) intracranial vessel wall (IVW) MRI. However, longitudinal 3D IVW studies are limited and ICAD evolution remains relatively unknown. PURPOSE: To evaluate ICAD changes longitudinally and to characterize the imaging patterns of atherosclerotic plaque evolution. STUDY TYPE: Prospective. POPULATION: 37 patients (69 ± 12 years old, 12 females) with angiography confirmed ICAD. FIELD STRENGTH/SEQUENCE: 3.0T/3D time-of-flight gradient echo sequence and T1- and proton density-weighted fast spin echo sequences. ASSESSMENT: Each patient underwent baseline and 1-year follow-up IVW. Then, IVW data from both time points were jointly preprocessed using a multitime point, multicontrast, and multiplanar viewing workflow (known as MOCHA). Lumen and outer wall of plaques were traced and measured, and plaques were then categorized into progression, stable, and regression groups based on changes in plaque wall thickness. Patient demographic and clinical data were collected. Culprit plaques were identified based on cerebral ischemic infarcts. STATISTICAL TESTS: Generalized estimating equations-based linear and logistic regressions were used to assess associations between vascular risk factors, medications, luminal stenosis, IVW plaque imaging features, and longitudinal changes. A two-sided P-value<0.05 was considered statistically significant. RESULTS: Diabetes was significantly associated with ICAD progression, resulting in 6.6% decrease in lumen area and 6.7% increase in wall thickness at 1-year follow-up. After accounting for arterial segments, baseline contrast enhancement predicted plaque progression (odds ratio = 3.61). Culprit plaques experienced an average luminal expansion of 10.9% after 1 year. 74% of the plaques remained stable during follow-up. The regression group (18 plaques) showed significant increase in minimum lumen area (from 7.4 to 8.3 mm2), while the progression group (13 plaques) showed significant decrease in minimum lumen area (from 5.4 to 4.3 mm2). DATA CONCLUSION: Longitudinal 3D IVW showed ICAD remodeling on the lumen side. Culprit plaques demonstrated longitudinal luminal expansion compared with their non-culprit counterparts. Baseline plaque contrast enhancement and diabetes mellitus were found to be significantly associated with ICAD changes. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 3.

Angiography-based hemodynamic features predict recurrent ischemic events after angioplasty and stenting of intracranial vertebrobasilar atherosclerotic stenosis.

OBJECTIVES: To assess the predictive value of hemodynamic features for stroke relapse in patients with intracranial vertebrobasilar atherosclerotic stenosis treated with percutaneous transluminal angioplasty and stenting (PTAS) using quantitative digital subtraction angiography (q-DSA). METHODS: In this retrospective longitudinal study, patients with intracranial vertebrobasilar atherosclerotic stenosis and who underwent PTAS treatment between January 2012 and May 2020 were enrolled. The q-DSA assessment was performed before and after PTAS. ROIs 1-4 were placed along the vertebral artery, proximal and distal basilar artery, and posterior cerebral artery; ROIs 5-8 were in 5 mm and 10 mm proximal and distal to the lesion, respectively. Relative time to peak (rTTP) was defined as the difference in TTP between ROIs. Cox regression analyses were performed to determine risk factors for recurrent stroke. RESULTS: A total of 137 patients (mean age, 62 years ± 10 [standard deviation], 83.2% males) were included, and 26 (19.0%) patients had stroke relapse during follow-up (median time of 42.6 months [interquartile range, 19.7-60.7]). Preprocedural rTTP4-1 (adjusted hazard ratio (HR) = 2.270; 95% CI 1.371-3.758; p = 0.001) and preprocedural rTTP8-5 (adjusted HR = 0.240; 95% CI 0.088-0.658; p = 0.006) were independently associated with the recurrent stroke. These hemodynamic parameters provided an incremental prognostic value for stroke relapse (AUC, 0.817 [0.704-0.931]; the net reclassification index, 0.431 [0.057-0.625]; and the integrated discrimination index, 0.140 [0.035-0.292]). CONCLUSIONS: In patients with intracranial vertebrobasilar atherosclerosis treated with PTAS, preprocedural prolonged TTP of the target vessel and shortened trans-stenotic TTP difference were associated with stroke relapse. Q-DSA-defined hemodynamic parameters provided incremental predictive value over conventional parameters for stroke recurrence. CLINICAL RELEVANCE STATEMENT: Quantitative DSA analysis enables intuitive observation and semi-quantitative evaluation of peri-therapeutic cerebral blood flow. More importantly, quantitative DSA-defined hemodynamic parameters have the potential for risk stratification of patients with intracranial atherosclerotic stenosis. KEY POINTS: Semi-quantitative angiography-based parameters can reflect pre- and postprocedural subtle changes in blood flow in patients with intracranial atherosclerotic stenosis. Although angioplasty procedures can significantly improve blood flow status, patients with more restricted baseline blood flow still show a higher risk of stroke recurrence. Angiography-based hemodynamic features possess prognostic value and can serve as clinical markers to assess stroke risk of patients with intracranial atherosclerotic stenosis.

Distinguishing Intracranial Diabetes-Related Atherosclerotic Plaques: A High-Resolution Magnetic Resonance Imaging-Based Radiomics Study.

INTRODUCTION: Diabetes markedly affects the formation and development of intracranial atherosclerosis. The study was aimed at evaluating whether radiomics features can help distinguish plaques primarily associated with diabetes. MATERIALS AND METHODS: We retrospectively analyzed patients who were admitted to our center because of acute ischemic stroke due to intracranial atherosclerosis between 2016 and 2022. Clinical data, blood biomarkers, conventional plaque features, and plaque radiomics features were collected for all patients. Odds ratios (ORs) with 95% confidence intervals (CIs) were determined from logistic regression models. The receiver operating characteristic (ROC) curve and area under the ROC curve (AUC) were used to describe diagnostic performance. The DeLong test was used to compare differences between models. RESULTS: Overall, 157 patients (115 men; mean age, 58.7 ± 10.7 years) were enrolled. Multivariate logistic regression analysis showed that plaque length (OR: 1.17; 95% CI: 1.07-1.28) and area (OR: 1.13; 95% CI: 1.02-1.24) were independently associated with diabetes. On combining plaque length and area as a conventional model, the AUCs of the training and validation cohorts for identifying diabetes patients were 0.789 and 0.720, respectively. On combining radiomics features on T1WI and contrast-enhanced T1WI sequences, a better diagnostic value was obtained in the training and validation cohorts (AUC: 0.889 and 0.861). The DeLong test showed the model combining radiomics and conventional plaque features performed better than the conventional model in both cohorts (p < 0.05). CONCLUSIONS: The use of radiomics features of intracranial plaques on high-resolution magnetic resonance imaging can effectively distinguish culprit plaques with diabetes as the primary pathological cause, which will provide new avenues of research into plaque formation and precise treatment.

Association of Dental Infections with Intracranial Atherosclerotic Stenosis.

INTRODUCTION: Periodontal disease (PD) and dental caries are oral infections leading to tooth loss that are associated with atherosclerosis and cerebrovascular disease. We assessed the hypothesis that PD and caries are associated with asymptomatic intracranial atherosclerosis (ICAS) in the Atherosclerosis Risk in Communities (ARIC) study. METHODS: Full-mouth clinical periodontal measurements (7 indices) collected at 6 sites per tooth from 6,155 subjects from the Dental Atherosclerosis Risk in Communities Study (DARIC) without prior stroke were used to differentiate seven PD stages (Periodontal Profile Class [PPC]-I to -VII) and dental caries on coronal dental surface (DS) and dental root surface (DRS). A stratified subset underwent 3D time-of-flight MR angiogram and 3D high isotropic-resolution black blood MRI. ICAS was graded according to the criteria established by the Warfarin-Aspirin Symptomatic Intracranial Disease (WASID) trial. We evaluated the relationship between PD stage and dental caries with asymptomatic ICAS, graded as no ICAS, <50% ICAS, and ≥50% ICAS. RESULTS: Among dentate subjects who underwent vascular imaging, 801 (70%) had no ICAS, 232 (20%) had <50% ICAS, and 112 (10%) had ≥50% ICAS. Compared to participants without gum disease (PPC-I), participants with mild-moderate tooth loss (PPC-VI), severe tooth loss (PPC-VII), and severe PD (PPC-IV) had higher odds of having <50% ICAS. Participants with extensive gingivitis (PPC-V) had significantly higher odds of having ≥50% ICAS. This association remained significant after adjusting for confounding variables: age, gender, race, hypertension, diabetes, dyslipidemia, 3-level education, and smoking status. There was no association between dental caries (DS and DRS) and ICAS <50% and ≥50%. CONCLUSION: We report significant associations between mild-moderate tooth loss, severe tooth loss, and severe PD with <50% ICAS as well as an association between extensive gingivitis and ≥50% ICAS. We did not find an association between dental caries and ICAS.

Balloon angioplasty as first-choice recanalization strategy for intracranial atherosclerosis-related emergent large vessel occlusion with small clot burden.

PURPOSE: The optimal primary recanalization strategy for intracranial atherosclerosis-related emergent large vessel occlusion (ICAS-ELVO) remains controversial. We aimed to explore the safety and efficacy of balloon angioplasty as the first-choice recanalization strategy for ICAS-ELVO with small clot burden. METHODS: Consecutive ICAS-ELVO patients presenting with microcatheter "first-pass effect" during endovascular treatment (EVT) were retrospectively analyzed. Patients were divided into preferred balloon angioplasty (PBA) and preferred mechanical thrombectomy (PMT) groups based on the first-choice recanalization strategy. The reperfusion and clinical outcomes between the two groups were compared. RESULTS: Seventy-six patients with ICAS-ELVO involving the microcatheter "first-pass effect" during EVT were enrolled. Compared with patients in the PMT group, those in the PBA group were associated with (i) a higher rate of first-pass recanalization (54.0% vs. 28.9%, p = .010) and complete reperfusion (expanded thrombolysis in cerebral ischemia ≥ 2c; 76.0% vs. 53.8%, p = .049), (ii) shorter puncture-to-recanalization time (49.5 min vs. 89.0 min, p < .001), (iii) lower operation costs (¥48,499.5 vs. ¥ 99,086.0, p < .001), and (iv) better 90-day functional outcomes (modified Rankin scale:0-1; 44.0% vs. 19.2%, p = .032). Logistic regression analysis revealed that balloon angioplasty as the first-choice recanalization strategy was an independent predictor of 90-day excellent functional outcomes for ICAS-ELVO patients with microcatheter "first-pass effect" (adjusted odds ratio = 6.01, 95% confidence interval: 1.15-31.51, p = .034). CONCLUSION: Direct balloon angioplasty potentially improves 90-day functional outcomes for ICAS-ELVO patients with small clot burden, and may be a more appropriate first-choice recanalization strategy than mechanical thrombectomy for these patients.

Plaque features of the middle cerebral artery are associated with periprocedural complications of intracranial angioplasty and stenting.

PURPOSE: The identification of plaque features in the middle cerebral artery (MCA) may help minimize periprocedural complications and select patients suitable for percutaneous transluminal angioplasty and stenting (PTAS). However, relevant research is lacking. METHODS: We retrospectively included patients with symptomatic MCA stenosis who received PTAS. All patients underwent intracranial vessel wall MRI (VWMRI) before surgery. Periprocedural complications (PC) included ischemic and hemorrhagic stroke within 30 days. Stenosis location, MCA shape, plaque eccentricity and distribution, plaque thickness and length, and enhancement ratio were compared between patients with and without PC. RESULTS: Sixty-six patients were included in the study, of which 12.1% (8/66) had PC. Of the eight patients with PC, seven (87.5%) had superior wall plaques. In the non-PC group (n = 58), nine (17%) patients had superior wall plaques. Compared with patients without PC, those with PC had more frequent superior wall plaques (17% vs 87.5%, p < 0.001) and s-shaped MCAs (19% vs 50%, p = 0.071), different stenosis locations (p = 0.012), thicker plaques (1.58 [1.35, 2.00] vs 1.98 [1.73, 2.43], p = 0.038), and less frequent inferior wall plaques (79.2% vs 12.5%, p < 0.001). Multivariate analysis showed that only the presence of superior wall plaques (OR = 41.54 [2.31, 747.54]) was independently associated with PC. CONCLUSION: MCA plaque features were highly correlated with PC in patients with symptomatic MCA stenosis who underwent PTAS.

The role of triglyceride-glucose index in the differential diagnosis of atherosclerotic stroke and cardiogenic stroke.

OBJECTIVE: This study aims to investigate the role of the triglyceride glucose (TyG) index in differentiating cardiogenic stroke (CE) from large atherosclerotic stroke (LAA). METHOD: In this retrospective study, patients with acute ischemic stroke were recruited from the First Affiliated Hospital of Soochow University, Lianyungang Second People's Hospital and Lianyungang First People's Hospital. Their general data, medical history and laboratory indicators were collected and TyG index was calculated. Groups were classified by the TyG index quartile to compare the differences between groups. Logistic regression was utilized to assess the relationship between the TyG index and LAA. The receiver operating characteristic curve (ROC) curve was used to evaluate the diagnostic efficiency of the TyG index in differentiating LAA from CE. RESULT: The study recruited 1149 patients. After adjusting for several identified risk factors, groups TyG-Q2, TyG-Q3, and TyG-Q4 had a higher risk of developing LAA compared to group TyG-Q1(odds ratio (OR) = 1.63,95% confidence interval (CI) = 1.11-2.39, OR = 1.72,95%CI = 1.16-2.55, OR = 2.06,95%CI = 1.36-3.09). TyG has certain diagnostic value in distinguishing LAA from CE(AUC = 0.595, 95%CI0.566-0.623;P<0.001). CONCLUSION: Summarily, the TyG index has slight significance in the identification of LAA and CE; it is particularly a marker for their preliminary identification.

Hemodynamic Characteristics of Intracranial Atherosclerotic Stenosis: A Pilot Study of Contrast Enhancement Time-Density Curves Based on Regions of Interest.

OBJECTIVE: The present study aimed to analyze the hemodynamic characteristics of occluded vessels responsible for acute ischemic stroke and to diagnose the occlusion types. METHODS: Multimodal computed tomography (CT) was used to accurately identify the range of occlusion of large intracranial vessels. Regions of interest (ROI 1-3 ) were manually delineated at sites 2 mm away from the proximal, middle, and distal portions of each occlusion, generating 3 contrast enhancement time-density curves. The peak CT attenuation values, or Hounsfield units (H 1-3 ), and time-to-peak values (T 1-3 ) were extracted from each curve. H 0 and T 0 of the time-density curve, based on ROI 0 of the automatically recognized input artery, were used as the baseline values with which the odds ratios of each parameter, H 1-3/0 and T 1-3/0 , were obtained. The present study aimed to establish prediction models for intracranial atherosclerotic stenosis (ICAS) based on each ROI's time-density curve. RESULTS: Among the 33 acutely occluded intracranial vessels, 10 were found to have ICAS, whereas 23 did not, based on the diagnostic criteria. Significant differences were observed in patient sex, neutrophil-to-lymphocyte ratio upon admission, Alberta Stroke Program Early CT Score 24-48 hours after reperfusion therapy, and H 1/0 , H 3/0 , and T 3/0 between the ICAS and non-ICAS groups ( P < 0.05). The prediction model (model 3) based on the ROI 3 time-density curve showed the best performance for the diagnosis of ICAS (area under the curve, 0.944; 95% confidence interval, 0.854-1.000). The prediction models based on ROI 1 (model 1) and ROI 2 (model 2) showed moderate diagnostic performance (area under the curve, 0.817 vs 0.822, respectively). The best visualization for proximal occlusions was in the first phase (arterial phase) of multiphase CT angiography, and in the second phase (early venous phase) for distal occlusions. CONCLUSIONS: The contrast enhancement time-density curves of the ROIs at all evaluated portions of the acute ischemic stroke occlusions provided a visual display of the blood flow characteristics of the responsible vessels. The time-density curve of the ROI placed 2 mm from the distal occlusion was a combined effect of residual blood flow and collateral establishment, thus providing good performance for the diagnosis of ICAS.

Intracranial arteriosclerosis and the risk of dementia: A population-based cohort study.

BACKGROUND: The impact of intracranial arteriosclerosis on dementia remains largely unclear. METHODS: In 2339 stroke-free and dementia-free participants (52.2% women, mean age 69.5 years) from the general population, we assessed intracranial carotid artery calcification (ICAC) and vertebrobasilar artery calcification (VBAC) as proxy for arteriosclerosis. Associations with dementia were assessed using Cox models. In addition, indirect effects through cerebral small vessel disease (cSVD) and subcortical brain structure volumes were assessed using causal mediation analyses. RESULTS: During a median of 13.4 years (25th-75th percentiles 9.9-14.5) of follow-up, 282 participants developed dementia. Both ICAC presence (hazard ratio [HR]: 1.53, 95% confidence interval [CI]: 1.00-2.32]) and volume (HR per standard deviation: 1.19, 95% CI: 1.01-1.40) increased dementia risk. For VBAC, severe calcifications increased dementia risk (HR for third vs first volume tertile: 1.89, 95% CI: 1.00-3.59). These effects were mediated partly through increased cSVD (percentage mediated for ICAC: 13% and VBAC: 24%). DISCUSSION: Intracranial arteriosclerosis increases the risk of dementia.

Central arterial stiffening and intracranial atherosclerosis: the atherosclerosis risk in communities neurocognitive study (ARIC-NCS): Aortic stiffness & intracranial atherosclerosis.

OBJECTIVES: Previous studies suggest an association between central arterial stiffness (CAS) and intracranial atherosclerotic disease (ICAD) among Asian participants with stroke or hypertension; this association has not been evaluated in United States populations. We assessed the cross-sectional association of CAS with ICAD presence and burden in late-life, and differences in association by age, sex, and race. MATERIALS AND METHODS: We conducted a cross-sectional analysis of 1,285 Atherosclerosis Risk in Communities Study participants [mean age 75 (standard deviation: 5) years, 38 % male, 20  % Black] at Visit 5 (2011-2013). CAS was measured as carotid-femoral pulse wave velocity (cfPWV) using the Omron VP-1000 Plus. ICAD was assessed using high-resolution vessel wall MRI and MR angiography. We evaluated associations of a 1 standard deviation (SD) cfPWV (3.02 m/s) and high vs. non-high cfPWV (≥ 13.57 m/s vs. < 13.57 m/s) with presence of plaques (yes/no) and plaque number (0, 1-2, and >2) using multivariable logistic and ordinal logistic regression models adjusted for covariates. RESULTS: Each one SD greater cfPWV was associated with higher odds of plaque presence (odds ratio (OR)=1.32, 95 % confidence interval (CI): 1.22, 1.43), and an incrementally higher odds of number of plaques (OR 1-2 vs. 0 plaques = 1.21, 95 % CI: 1.10, 1.33; OR >2 vs. 0 plaques = 1.51, 95 % CI: 1.33,1.71). Results suggested differences by race, with greater magnitude associations among Black participants. CONCLUSIONS: CAS was positively associated with ICAD presence and burden; cfPWV may be a useful subclinical vascular measure for identification of individuals who are at high risk for cerebrovascular disease.

Balloon-mounting stent versus balloon angioplasty for intracranial arterial stenosis: A systematic review and meta-analysis.

BACKGROUND: Intracranial artery atherosclerotic stenosis (ICAS) is a major cause of stroke, especially in Asian countries. Current treatment options, including balloon-mounted stent (BMS) and balloon angioplasty (BA), lack sufficient evidence to determine a preferred approach. This systematic review and meta-analysis aimed to compare the efficacy and safety of BMS and BA in treating ICAS. METHODS: Following PRISMA 2020 guidelines, we conducted a comprehensive search in PubMed, Web of Science, and Scopus up to December 1, 2023. Eligible studies compared BMS with BA in patients diagnosed with ICAS. Primary outcomes included the success rate and occurrence of stroke (ischemic or hemorrhagic). Secondary outcomes were perforator occlusion, in-stent thrombosis, death, and restenosis. Statistical analysis was conducted using R software version 4.3.1, employing a random-effects model. RESULTS: Five high-quality studies involving 707 patients (515 males, 192 females) were included. BMS had a significantly higher success rate compared to BA (Risk Ratio [RR]: 1.13; CI: 1.03 to 1.24, p < 0.01; I2 = 14 %). The overall risk for stroke (ischemic and hemorrhagic) was significantly higher in BMS (RR: 2.97; CI: 1.32 to 6.67, p < 0.01; I2 = 0 %). However, no significant difference was found between BMS and BA regarding ischemic stroke (RR: 2.33; CI: 0.80 to 6.74, p = 0.12; I2 = 0 %). Additionally, no significant differences were observed in terms of perforator occlusion, in-stent thrombosis, dissection, minor and major strokes, and mortality rates. BMS was associated with a lower risk of restenosis (RR: 0.31; 95 % CI: 0.12 to 0.83, p = 0.02; I2 = 0 %). CONCLUSION: Our results indicate that BMS might be associated with higher success and lower restenosis rates than BA in the treatment of ICAS but with an increased overall risk of stroke. No significant differences were observed in ischemic stroke, perforator occlusion, in-stent thrombosis, dissection, minor and major strokes, and mortality rates. The choice of treatment should consider these findings, alongside the technical challenges and desired angiographic outcomes. Future randomized controlled trials are necessary to further elucidate these results.

Common and distinct risk profiles of asymptomatic extra- and intracranial atherosclerosis in the Nagahama cohort.

BACKGROUND AND PURPOSE: Atherosclerotic burden increases the risk of both extracranial internal carotid artery stenosis (ICS) and intracranial large artery disease (ICAD). However, the differences in risk profiles have not been thoroughly investigated. METHODS: Participants were recruited from the Nagahama study cohort in Japan. Individuals over 60 years old who underwent 1.5-T head and neck magnetic resonance angiography (MRA) between July 2013 and February 2017 were included. ICAD was defined as WASID ≥ 50 %, and ICS was defined as NSCET ≥ 30 %. The prevalence and association of risk factors, including proatherogenic and proinflammatory factors, and the p.R4810K variant in the RNF213 gene, were investigated. Multivariable logistic regression analyses were performed. RESULTS: A total of 3089 individuals participated in the study, with a mean age of 68.1 ± 5.3 years, and 36.0 % were males. Among them, 52 (1.7 %) had ICS, 119 (3.8 %) had ICAD, and 15 (0.49 %) had both conditions. Alopecia areata was an independent predictor for both ICS (Odds ratio [OR] 3.5; 95 % CI 1.3-8.3) and ICAD (OR 2.1; 95 % CI 1.0-3.9). Diabetes (OR 3.7; 95 % CI 2.0-7.0) and older age (OR 2.4; 95 % CI 1.2-4.5) were associated only with ICS, while the RNF213 variant was associated with only ICAD (OR 5.7; 95 % CI 1.6-16.0). ICS and ICAD were also independently associated with each other. CONCLUSIONS: In this MRA-based large scale study, alopecia areata, known as a systemic inflammatory disease, was shown to be a common risk factor for ICS and ICAD. While conventional atherosclerotic factors were associated with ICS, non-atherosclerotic factors appear to contribute to ICAD in Japan.

Association of systemic inflammatory response index and plaque characteristics with the severity and recurrence of cerebral ischemic events.

AIM: We aimed to investigate the relationship between systemic inflammatory response index (SIRI) and intracranial plaque features, as well as the risk factors related to the severity and recurrence of cerebral ischemic events. METHODS: We enrolled 170 patients with cerebral ischemic events. Baseline demographic characteristics and laboratory indicators were collected from all participants. All patients were assessed by high-resolution magnetic resonance vessel wall imaging for culprit plaque characteristics and intracranial atherosclerotic burden. Outpatient or telephone follow-up were conducted at 1, 3, and 6 months after discharge. RESULTS: SIRI levels were significantly associated with the enhanced plaque number (r = 0.205, p = 0.007), total plaque stenosis score (r = 0.178, p = 0.020), total plaque enhancement score (r = 0.222, p = 0.004), intraplaque hemorrhage (F = 5.630, p = 0.004), and plaque surface irregularity (F = 3.986, p = 0.021). Higher SIRI levels (OR = 1.892), total plaque enhancement score (OR = 1.392), intraplaque hemorrhage (OR = 3.370) and plaque surface irregularity (OR = 2.846) were independent risk factors for moderate-severe stroke, and these variables were significantly positively correlated with NIHSS (P < 0.05 for all). In addition, higher age (HR = 1.063, P = 0.015), higher SIRI levels (HR = 2.003, P < 0.001), and intraplaque hemorrhage (HR = 4.482, P = 0.008) were independently associated with recurrent stroke. CONCLUSIONS: Higher SIRI levels may have adverse effects on the vulnerability and burden of intracranial plaques, and links to the severity and recurrence of ischemic events. Therefore, SIRI may provide important supplementary information for evaluating intracranial plaque stability and risk stratification of patients.

Differences in intracranial atherosclerosis plaque between posterior circulation and anterior circulation on high-resolution magnetic resonance imaging: A systematic review and meta-analysis.

OBJECTIVE: The clinical characteristics and mechanisms of stroke caused by anterior circulation atherosclerotic plaques (ACAPs) and posterior circulation atherosclerotic plaques (PCAPs) are distinct. We aimed to compare the differences in vulnerability, morphology, and distribution between ACAPs and PCAPs based on hign-resolution magnetic resonance imaging (HR-MRI). MATERIALS AND METHODS: The PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure (CNKI), and Wanfang database were retrieved from inception through May 2023. Meta-analysis was performed by R 4.2.1 software. The quality of the literature was assessed by the Agency for Healthcare Research and Quality (AHRQ). Subgroup analysis was conducted to explore the heterogeneity of the pooled results. RESULTS: There were a total of 13 articles, including 1194 ACAPs and 1037 PCAPs. The pooled estimates demonstrated that the incidence of intraplaque hemorrhage in the PCAPs was higher (OR 1.72, 95%CI 1.35-2.18). The plaque length (SMD 0.23, 95%CI 0.06-0.39) and remodeling index (SMD 0.29, 95%CI 0.14-0.44) of PCAPs were larger than those in ACAPs. However, there were no evident differences in significant enhancement or stenosis degree between the two groups. CONCLUSION: There were more unstable features in PCAPs, highlighting an elevated risk of recurrent ischemic stroke in the posterior circulation. Furthermore, PCAPs were prone to developing penetrating artery disease due to their wider distribution. Nevertheless, posterior circulation arteries exhibited a greater propensity for outward remodeling, which may lead treatment team to miss the optimal intervention stage by being overlooked on angiographic detection.