Background: Patients with diabetes have accelerated atherosclerosis progression, but the underlying mechanisms are not fully understood. Dynamic contrast-enhanced magnetic resonance imaging has allowed in vivo characterization of plaque neovasculature, which plays a critical role in plaque progression. We aimed to evaluate the impact of diabetes on carotid plaque neovasculature as assessed by dynamic contrast-enhanced magnetic resonance imaging. Methods: Patients with recent ischemic stroke and ipsilateral carotid plaque underwent multicontrast magnetic resonance imaging for characterizing plaque morphology and dynamic contrast-enhanced magnetic resonance imaging for pharmacokinetic parameters of plaque neovasculature, including transfer constant ( K trans , reflecting flow, endothelial surface area, and permeability) and fractional plasma volume ( ν p ). Results: Sixty-five patients were enrolled, including 30 patients with diabetes (years since diagnosis: median 5.0 [interquartile range, [3.0–12.0]) and 35 patients without diabetes. Subjects with diabetes had a greater plaque burden and a higher prevalence of high-risk characteristics. Additionally, carotid plaques in the subjects with diabetes showed higher K trans than those in the subjects without diabetes (0.100±0.048 min -1 versus 0.067±0.042 min -1 , P =0.005) but ν p was numerically lower in the subjects with diabetes (5.2±3.7% versus 6.2±4.3%, P =0.31). The association of diabetes with high K trans (β=0.033, P =0.005) was independent of patient and plaque characteristics and remained largely intact after adjusting for serum lipids, glucose, or hs-CRP (high-sensitivity C-reactive protein). However, it became nonexistent after adjusting for hemoglobin A1c (β=−0.010, P =0.49). Conclusions: Dynamic contrast-enhanced magnetic resonance imaging of carotid plaques suggested that plaque neovasculature in patients with diabetes is leaky, indicating enhanced capability of bringing blood constituents and facilitating extravasation of inflammatory cells, erythrocytes, and plasma proteins. Leaky plaque neovasculature correlated with hemoglobin A1c and may play a role in accelerated atherosclerosis progression in diabetes.

Background: Intracranial atherosclerotic disease (ICAD) tends to affect multiple arterial segments, and previous studies rarely performed a comprehensive plaque analysis of the entire circle of Willis for the evaluation of recurrent stroke risk. We aimed to investigate the features of circle of Willis ICAD on 3D magnetic resonance vessel wall imaging (MR-VWI) and their relationships with recurrent acute stroke. Methods: Patients with either acute ischemic stroke (within 4 weeks after stroke) or chronic ischemic stroke (after 3 months of stroke) due to intracranial atherosclerotic plaque underwent 3D contrast-enhanced MR-VWI covering major cerebral arteries. Participants were divided into three groups: first-time acute stroke, recurrent acute stroke, and chronic stroke. Culprit plaque (defined as the only lesion or the most stenotic lesion when multiple plaques were present within the same vascular territory of the stroke) and non-culprit plaque characteristics, including total plaque number, plaque thickness, plaque area, plaque burden (calculated as plaque area divided by outer wall area), enhancement ratio (ER), eccentricity, and stenosis, were measured and compared across the three groups. Associations between plaque characteristics and recurrent acute stroke were investigated by multivariate analysis. Results: A total of 176 participants (aged 61 ± 10 years, 109 men) with 702 intracranial plaques were included in this study. There were 80 patients with first-time acute stroke, 42 patients with recurrent acute stroke, and 54 patients with chronic stroke. More intracranial plaques were found per patient in the recurrent acute stroke group than in the first-time acute stroke or chronic stroke group (5.19 ± 1.90 vs. 3.71 ± 1.96 and 3.46 ± 1.33, p < 0.001). Patients in the recurrent acute stroke group had greater culprit plaque burden ( p < 0.001) and higher culprit ER ( p < 0.001) than the other two groups. After adjustment of clinical demographic factors, in multivariate analysis, coronary artery disease (CAD) (odds ratio, OR = 4.61; p = 0.035), total plaque number ( OR = 1.54; p = 0.003), culprit plaque ER ( OR = 2.50; p = 0.036), and culprit plaque burden ( OR per 10% increment = 2.44; p = 0.010) were all independently associated with recurrent acute stroke compared to the first-time acute stroke. Conclusion: Increased intracranial atherosclerotic plaque number, higher culprit plaque ER, greater culprit plaque burden, and CAD are independently associated with recurrent acute stroke.

Background 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. Purpose 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. Study Type Prospective. Population Two hundred and eighty‐eight symptomatic patients with acute ischemic stroke due to intracranial atherosclerotic plaque. Field Strength/Sequence T 1 WI volume isotropic turbo spin‐echo acquisition sequence at 3.0 T. Assessment 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. Statistical Tests 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. Results 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. Data Conclusion 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. Level of Evidence 1 Technical Efficacy Stage 3

Background Intracranial aneurysms (IAs) are common in the population and current imaging-based rupture risk assessment needs to be refined. We aimed to use four-dimensional CT angiography (4D-CTA) to investigate the associations of irregular pulsation of IAs with conventional risk factors and the estimated rupture risk. Methods One hundred and five patients with 117 asymptomatic IAs underwent 4D-CTA. Geometric and morphologic parameters were measured and the presence of irregular pulsation (defined as a temporary focal protuberance ≥1 mm on more than three successive frames) was identified on 4D-CTA movies. One- and 5 year aneurysm rupture risk were estimated using UCAS and PHASES calculators. Univariate and multivariate analyses were performed to investigate the conventional risk factors associated with irregular pulsation. Results Irregular pulsation was observed in 41.0% (48/117) of IAs. Aneurysm size (OR=1.380, 95% CI 1.165 to 1.634), irregular shape (OR=3.737, 95% CI 1.108 to 12.608), and internal carotid artery location (OR=0.151, 95% CI 0.056 to 0.403) were independently associated with irregular pulsation (P<0.05). Aneurysms with irregular pulsation had more than a 6-fold higher estimated rupture risk (1- and 5-year risk [95% CI], 1.56% [0.42%–3.91%], and 2.40% [1.30%–4.30%], respectively) than aneurysms without irregular pulsation (0.23% [0.14%–0.78%] and 0.40% [0.40%–1.30%], respectively) (P<0.001). Conclusions IAs with irregular pulsation are associated with larger size, irregular-shape, and non-ICA origin, and have more than a 6-fold higher estimated 1- and 5-year rupture risk than aneurysms without irregular pulsation. Irregular pulsation should be validated in future longitudinal studies to determine its predictive value for aneurysm growth and rupture.

目的·探索颈动脉支架置入术前动态增强磁共振成像(dynamic contrast-enhanced MR imaging,DCE-MRI)预测术后支架内再狭窄发生的价值.方法·选取40例拟行颈动脉支架置入术的颈动脉粥样硬化斑块患者病例资料进行前瞻性分析.在术前1周内完成颈动脉血管壁磁共振成像(vessel wall MR imaging,VW-MRI)及DCE-MRI成像,应用颈动脉造影检查判断患者在术后第6个月是否发生再狭窄.评估DCE-MRI与支架内再狭窄的相关性.结果·再狭窄患者组Ktrans和vP显著高于无再狭窄组(P=0.000,P=0.037),Ktrans可独立预测支架内再狭窄(OR=1.43,95％CI 1.17～1.56,P=0.012),最佳阈值为0.09 min-1(敏感度为100％,特异度为87.5％).结论·斑块内的炎症活动可能引起支架置入后的内膜过度增生;Ktrans可独立预测颈动脉支架术后再狭窄的发生,有望成为预测支架内再狭窄发生的有效手段.

目的 以DSA为金标准,探讨三维血管壁磁共振成像(3D-VW-MRI)诊断大脑中动脉(MCA)粥样硬化性狭窄程度的临床价值.方法 收集上海仁济医院收治的46例缺血性脑血管病患者.均在人院1周内完成颈动脉3.0T 3D-VW-MRI和DSA检查,分别评价MCA狭窄程度和病变累及范围.将狭窄程度分为轻度(＜49.9％)、中度(50％～69.9％)、重度(70％～99.9％)和闭塞,并以DSA作金标准,分别计算其灵敏度、特异度、阳性预测值、阴性预测值,Pearson相关系数和Bland-Altman分析评价3D-VW-MRI和DSA测量结果的相关性和一致性.结果 46例共有92段MCA完成3D-VW-MRI和DSA检查.3D-VW-MRI诊断MCA狭窄/闭塞灵敏度、特异度、阳性预测值、阴性预测值显示,轻度狭窄分别为88.2％、92％、71.4％、97.2％,中度狭窄分别为60％、97.4％、81.8％、92.6％,重度狭窄分别为78.6％、94.9％、73.3％、96.1％,闭塞分别为100％、97.6％、83.3％、100％.两种检查手段测量管腔狭窄和病变长度呈正相关(r值分别为0.940、0.977,P值均＜0.001),Bland-Altman分析表明两种检测方法具有较好一致性.结论 3D-VW-MRI评价MCA狭窄程度与DSA有高度一致性.凭借其分辨率高、扫描范围大、无创性特点,一定程度上可替代DSA,作为MCA粥样硬化性狭窄/闭塞性疾病的常规筛查手段.

The superficial femoral artery (SFA) is a typical atherosclerosis-prone site. We aimed to explore whether the tortuosity of the SFA associates with the occurrence of atherosclerosis and investigate how vascular tortuosity influences the characteristics of blood flow. Ten patients diagnosed with atherosclerotic disease in their SFAs while free of systemic atherosclerosis risk factors were enrolled together with ten atherosclerosis-free patients. The tortuosity of each SFA was quantitatively evaluated by calculating the averaged curvature (AC), maximum curvature (MC) and fraction of high curvature (FC) based on the geometrical model reconstructed from medical images. Hemodynamic studies were performed using both geometrically simplified and anatomically realistic models of the SFA to systematically address the hemodynamic effects of vascular tortuosity. Morphological analyses revealed that all curvature indices of the SFA were significantly larger in patients with atherosclerosis than in atherosclerosis-free patients (AC [mm−1]: 0.034 ± 0.016 vs. 0.018 ± 0.006; MC [mm−1]: 0.055 ± 0.023 vs. 0.034 ± 0.008; FC [%]: 22.77 ± 10.22 vs. 11.39 ± 6.82; p < 0.001). Simulations of blood flows in the geometrically simplified SFAs showed that increasing vascular curvature caused a progressive increase in the area ratios of low wall shear stress (LWSA) and high oscillatory shear index (HOSA). Hemodynamic studies on the anatomically realistic SFAs further demonstrated that high-curvature SFAs (n = 10) had overall larger LWSA and HOSA compared with low-curvature SFAs (n = 10) (LWSA [%]: 4.13 ± 1.91 vs. 1.79 ± 1.13, p = 0.009; HOSA [%]: 4.95 ± 1.92 vs. 2.37 ± 1.51, p = 0.007). These results suggest that increased vascular tortuosity augments the severity and distribution of atherosclerosis-promoting flow disturbances in the SFA and may be an independent risk factor for atherosclerosis.

Flow diverter (FD) devices have been widely employed to treat cerebral aneurysms. Despite the well-documented clinical benefits, considerable inter-patient variability in clinical outcome has been reported, which implies the necessity of patient-specifically evaluating hemodynamic changes following FD treatment, especially those associated with posttreatment intra-aneurysmal thrombus formation or complications. Computational fluid dynamics (CFD) methods, owing to the advantages in hemodynamic quantification, cost, and flexibility over traditional in vivo measurement or in vitro experiment methods, have increasingly become a major means for addressing hemodynamic problems related to FD treatment. Relevant CFD-based studies have extensively demonstrated that the results of hemodynamic computation can reasonably explain the clinical outcomes in different patient cohorts and provide useful insights for guiding the selection or optimization of FD devices. Nevertheless, CFD models are inherently unable to predict FD implantation-induced mechanical changes in the walls of aneurysm and its parent artery. In addition, the boundary conditions of most existing CFD models were not fully personalized for purpose of simplicity or due to the difficulty of measuring flow velocity in near-aneurysm regions, which may however considerably compromise the fidelity of the models in reproducing in vivo hemodynamics. To address these issues, the following studies would be expected: (1) perform fluid structure interaction simulations to explore the associations between wall stress/tension and posttreatment adverse vascular remodeling or aneurysm rupture, and (2) develop geometrical multiscale models based on available in vivo data to generate patient-specific boundary conditions for CFD models localized to aneurysm regions.

BACKGROUND AND PURPOSE: Fractional flow measured on 3D-TOF-MRA was proposed to quantify cerebral hemodynamic changes in patients with artery stenosis. We investigated the association between fractional flow and cerebral perfusion changes in patients with symptomatic MCA stenosis. MATERIALS AND METHODS: This prospective study was approved by the institutional review board, and all participants provided written informed consent. From June 2015 to May 2018, four hundred twenty-nine patients with symptomatic intracranial arterial stenosis were consecutively recruited and underwent conventional brain MR imaging, 3D-TOF-MRA, and brain CTP. A total of 91 patients with unilateral M1 segment stenosis of the MCA and a stenosis degree of 50%similar to 99% were included in the analysis. Fractional flow was measured by comparing distal and proximal signal intensity changes across the stenosis on 3D-TOF-MRA. The cutoff value for fractional flow for discriminating between normal perfusion and hypoperfusion was obtained from the receiver operating characteristic curve. Associations between fractional flow and hypoperfusion were assessed using univariate and multivariate analyses. RESULTS: The receiver operating characteristic curve showed a significant fractional flow threshold value at 0.90 (sensitivity, 70.1%; 95% CI, 55.9%-81.2%; specificity, 69.6%; 95% CI, 47.6%-84.1%). Participants with a fractional flow of <= 0.90 were independently associated with cerebral hypoperfusion downstream from the stenosis site (adjusted OR, 3.68; 95% CI, 1.63-11.62; P = .027). CONCLUSIONS: Fractional flow measured on 3D-TOF-MRA may serve as a noninvasive and practical tool for determining the cerebral hypoperfusion in patents with symptomatic MCA stenosis.

The importance of properly treating boundary conditions (BCs) in numerical simulation of hemodynamics in intracranial aneurysm (IA) has been increasingly recognized. In this study, we constructed three types of computational model for each IA to investigate how the outcome of numerical simulation is affected by the treatment of BCs. The first type of model (i.e., Type-A model) was obtained by applying 3-D hemodynamic modeling to the entire cerebral arterial network, with its solution being taken as the reference for evaluating the performance of the other two types of model (i.e., Type-B and Type-C models) in which 3-D modeling was confined to the aneurysm region. In addition, patient-specific 1-D models of the cerebral arterial network were developed to provide hemodynamic information for setting the inflow/outflow BCs of the 3-D models. Numerical tests on three IAs revealed that prescribing the outflow BCs of a localized 3-D aneurysm model based on 1-D model-simulated outflow division (i.e., Type-B model) instead of imposing the free outflow BC on all outlets (i.e., Type-C model) helped to improve the fidelity of the simulation of intra-aneurysmal hemodynamics, but could not guarantee a complete reproduction of the reference solution obtained by the Type-A model. Moreover, it was found that the outcome of hemodynamic simulation was more sensitive to the treatment of BCs when an aneurysm was located at arterial bifurcation rather than sidewall. These findings highlight the importance of taking into account systemic cerebroarterial hemodynamics in computational modeling of hemodynamics in IAs, especially those located at bifurcations.

目的:探索3.0T动态增强磁共振成像(dynamic contrast-enhanced magnetic resonance imaging,DCE-MRI)评价颈动脉粥样硬化斑块稳定性的效能.方法:对66例超声检查显示颈动脉内膜增厚 ≥2 mm的患者,行颈动脉磁共振管壁成像(vessel wall magnetic resonance imaging,VW-MRI)及DCE-MRI扫描,并依据MRI修正的美国心脏协会(American Heart Association,AHA)斑块分型标准,对颈动脉斑块进行分型与定性(Ⅳ～Ⅵ型为不稳定斑块,余为稳定斑块),计算DCE-MRI药代动力学参数(Ktrans、kep、ve和vp),评估各参数与斑块分型、斑块稳定性间的相关性,以及各参数区分稳定斑块与不稳定斑块的效能.结果:Ktrans、kep均与MRI修正的AHA分型(Ⅲ～Ⅵ型)呈显著正相关(ρ=0.532,P<0.001;ρ=0.409,P<0.001).Ktrans、kep可区分稳定斑块与易损斑块,其最佳临界值分别为0.043/min(此时诊断灵敏度为83％,特异度为100％)和0.741/min(诊断灵敏为77％,特异度为91％).结论:DCE-MRI药代动力学参数Ktrans、kep可定量评估颈动脉斑块的稳定性,是斑块危险性分层的影像学标志物.

Prospective observation of hemodynamic changes before and after the formation of atherosclerotic stenosis in the carotid artery is difficult. Thus, a vessel surface repairing method was used for retrospective hemodynamic study before and after atherosclerotic stenosis formation in carotid artery. The three-dimensional geometry of sixteen sinus atherosclerotic stenosis carotid arteries were repaired and restored as normal arteries. Computational fluid dynamics analysis was performed to estimate wall shear stress (WSS), velocity and vortex in atherosclerosis-free areas and sinus in stenosis-repaired carotid artery. The analysis was also performed in the stenotic segment and upstream and downstream of stenosis in stenotic carotid artery. Compared to the atherosclerosis-free areas in stenosis-repaired carotid artery, sinus presented significantly lower WSS (P < 0.05), lower velocity (P < 0.05) and apparent vortex. Compared to the sinus, the WSS in the upstream of stenosis was lower (P < 0.05), while in the downstream area was similar (P = 0.87), both upstream and downstream of stenosis demonstrated similar velocity to sinus (P = 0.76 and P = 0.36, respectively) and apparent vortex. Atherosclerosis-prone areas including normal carotid sinus and upstream and downstream of stenosis in stenotic carotid artery were subjected to lower WSS and velocity as well as apparent vortex, thereby might be associated with the formation and progress of atherosclerosis.

This study was to analyze the in vivo distribution of wall shear stress (WSS), velocity and inplane pressure difference in normal carotid artery by using computational fluid dynamics (CFD) based on contrastenhanced MRA (CE-MRA) data and to determine whether there were differences in these hemodynamic parameters between atherosclerosis-free and atherosclerosis-prone areas.CE-MRA was performed on 16 normal carotid arteries to obtain carotid three-dimensional surface data.CFD analysis was then performed to estimate those parameters in atherosclerosis-free (distal common carotid artery and distal internal carotid artery) and atherosclerosis-prone (carotid bifurcation) areas.One-way analysis of variance (ANOVA) was conducted to analyze differences among these three areas.CFD analysis revealed that WSS and velocity were significantly lower in carotid bifurcation compared to distal common carotid artery (CCA) (P =0.011, P <0.001, respectively) and distal internal carotid artery (ICA) (P <0.001, P <0.001, respectively).While in-plane pressure difference was significantly higher in carotid bifurcation compared to distal CCA (P <0.001) and distal ICA (P =0.005).Hemodynamic environment in carotid bifurcation of normal carotid artery which assessed by using CFD analysis appeared to be with lower WSS and lower velocity, while with higher in-plane pressure difference.These characterizations might facilitate the initiation of atherosclerosis.

Objective This study aimed to investigate the correlation between the carotid plaque magnetic resonance imaging (MRI) characteristics and acute cerebral infarction focus features in patients with type 2 diabetes mellitus (DM). Methods It was a cross section study. Patients with acute cerebrovascular syndrome in internal carotid artery territory were recruited and the cardiogenic factors were excluded. All patients underwent both carotid and brain MRI scans including magnetic resonance angiography (MRA) and diffusion-weighted imaging (DWI) within 1 week of symptom onset. Ipsilateral carotid plaque morphological and compositional characteristics intracranial and extracranial carotid arteries stenosis were also determined. Acute cerebral infarction patterns and size were evaluated on DWI. Results Of the 140 patients been recruited, 68 (48.6%) patients had DM. The multivariate analysis showed that DM was found to be an independent risk factor for the presence of lipi-rich necrotic core (LRNC) plaque [odds ratio (OR) 3.35, 95% confidence interval (CI) 1.33-8.43], and type 2 DM patients exhibited higher prevalence of carotid type IV-VI lesions, larger plaque burden as well as larger lipid-rich necrotic core plaques compared with non-DM patients. Among the patients with carotid LRNC plaque on symptomatic side, larger acute cerebral infarction size and more concomitant large perforating artery infarct patterns in the internal carotid artery territory were found in DM group than those of non-DM group[(15.45±8.97)ml vs(9.09±8.64)ml,P=0.011;34.0% vs 13.2%, P=0.024]. Conclusion This study shows that more concomitant large perforating artery infarct patterns in the internal carotid artery territory are found in the type 2 DM patients with ipsilateral carotid plaque features, particularly the LRNC, than those of non-DM patients. Quantification of the carotid plaque characteristics by MRI combined DM has the potential usefulness for stroke risk stratification and individualized diagnosis and treatment.

This study sought to reveal the effect of angiotensin II (Ang II)-induced atherosclerotic vulnerability in rabbits and to determine whether in vivo magnetic resonance imaging (MRI) can determine the effect of Ang II on atherosclerotic development over time. In total, 24 elderly male New Zealand white rabbits underwent an intravascular balloon injury in the left common carotid artery (LCCA) and were subsequently fed a high cholesterol diet for 12 weeks. At 8 weeks, rabbits were randomly assigned to receive either Ang II (1.4 mg/kg/d, Ang II group) or vehicle (phosphate-buffered saline, control) via a subcutaneous osmotic minipump for 4 weeks. The rabbits were imaged three times: at baseline and at 8 and 12 weeks. After the 12-week MRI scanning, rabbits were euthanized to obtain pathological and histological data. Atherosclerotic plaques were identified in the 21 rabbits that survived the 12-week trial. Typical feature of vulnerable plaques (VP), intraplaque hemorrhage, were observed in 6 of 10 animals (60.0%) in the Ang II group. The Cohen K value of MR imaging between the AHA classifications was 0.82 (0.73–0.91; P < 0.001). MRI revealed that the change in carotid morphology were significantly different between the Ang II and control group plaques. Our results support an important role for Ang II in plaque vulnerability by promoting intraplaque neovascularization and hemorrhage as well as inflammation. The vulnerable features induced by Ang II in rabbit carotid plaques could be accurately monitored with MRI in vivo and confirmed with histomorphology.

Objective The present study of magnetic resonance black blood imaging (MRI)-identified carotid atherosclerotic lesions in hypertensive patients with acute stroke and sought to determine the associations between HbA1 c level and carotid vulnerable plaque characteristics and acute cerebral infarction (ACI) severity.Methods 153 patients with acute stroke were enrolled;stratified into high (≥6.5％) and low (＜6.5％) HbA1c groups;and underwent carotid and brain MRI to assess carotid plaque features and ACI volume in the region supplied by the internal carotid artery (ICA) in the symptomatic side.Results Plaque burden [percent wall volume (PWV),max wall thickness (max-WT)] and lipidrich necrotic core (LRNC) were larger in the high as compared to the low HbA1 c group.High HbA1 c was an independent risk factor for the presence of plaque (odds ratio [OR] =3.71) and LRNC plaque (OR =7.08).HbA1c independently correlated with ACI severity among patients with ICA region cerebral infarction and carotid plaque.Conclusion Our study suggested that an elevated HbA1c may have an adverse effect on carotid plaque vulnerability especially those with larger LRNC volumes in hypertensive stroke patients,which might exacerbate the severity of ACIs.

Objectives: This study sought to compare the atherosclerotic plaque burden between middle cerebral artery (MCA) and extracranial carotid artery (ECA) in ischemic stroke patients using high-resolution, black-blood (HR BB) MRI and to investigate the relationship between plaque burden found in both arteries and stroke severity.Methods: All subjects with recent ischemic stroke underwent MCA and ECA HR BB MRI at 3.0 Tesla. For each artery segment, the thickness, area and signal intensities of plaques were recorded. Plaque burden, as measured by normalized wall index (NWI=wall area/total vessel areax100%) were calculated. All patients received a clinical stroke severity score as measured by the National Institutes of Health Stroke Scale (NIHSS) scores at the time of admission.Results: A total of 65 stroke subjects were included in the final analysis. MCA exhibited significantly greater NWI than the ipsilateral ECA (symptomatic MCA vs. ECA: 58.048.19 vs. 37.53 +/- 10.25, p<0.001; asymptomatic MCA vs. ECA: 53.80 +/- 4.49 vs. 34.85 +/- 4.27, p<0.001, respectively). NWI in symptomatic MCA and ECA were significantly associated with NIHSS scores (r=0.779 vs. 0.645; p<0.001 respectively). Moreover, stronger statistical correlations between NIHSS scores and NWI were found in MCA, as compared with ECA during multivariate linear regression analysis.Conclusion: Greater atherosclerotic plaque burden and a closer association with stroke severity were found for the MCA as compared to the ipsilateral ECA. Identification of MCA plaque lesions by MRI may be helpful for developing more aggressive strategies for stroke prevention.

Type 2 diabetes mellitus (T2DM) might aggravate the carotid plaque vulnerability, and increase the risk for ischemic stroke. Few studies reported the acute stroke subtype with carotid plaque characteristics in T2DM patients. This study aimed to investigate the association between carotid plaque characteristics and acute cerebral infarct (ACI) lesion features determined by MRI in T2DM patients.

Purpose:To evaluate the diagnostic value of dual source computer tomography angiography (DSCTA) in judging the plaque quantity and stability in intermediate stenosis coronary artery with the intravascular ultrasound (IVUS) as the gold standard.Methods:Sixty-two cases (83 sites) of intermediate lesions were confirmed by coronary angiography (CAG).Twenty-five male and 37 female patients were undergone DSCTA one to two weeks before coronary angiography and intravascular ultrasound (IVUS) examination.The results of IVUS were taken as the gold standard.External elastic membrane cross sectional area (EEMCSA),minimal lumen area (MLA),plaque area (PA),plaque burden (PB),rate of narrow area and remodeling index (RI) were analyzed and compared.The sensitivity,specificity,positive predictive value,negative predictive value and accuracy of DSCTA in diagnosing vulnerable plaques were determined.Results:There was no significant difference of the stenosis ratio of intermediate lesions in coronary artery between DSCTA and IVUS.The values of EEMCSA,MLA,PA,PB,and RI were not with significantly difference and the correlation was good between DSCTA with IVUS.The sensitivity,specificity,positive predictive value,negative predictive value and accuracy of DSCTA in diagnosing vulnerable plaque in 83 intermediate lesions were 72.92％、74.29％、79.55％,66.67％ and 73.49％,respectively.Conclusion:DSCTA had a high diagnostic value in both the quantification of intermediate plaques and the qualitative analysis of vulnerable plaques with the intravascular ultrasound (IVUS) as the gold standard,and can be used as the first choice for risk stratification and follow-up of coronary heart disease.