Irregular surface of carotid atherosclerotic plaque is associated with ischemic stroke: a magnetic resonance imaging study

Objective To determine the association between the irregularity of carotid plaque surface using multidimensional magnetic resonance imaging(MRI) of ipsilateral acute cerebral infarction(ACI) cases. Methods Patients with recent cerebrovascular symptoms(stroke or transient ischemic attack < 2 weeks) and atherosclerotic plaque in at least one carotid artery were diagnosed by B-mode ultrasound imaging(intima-media thickness ≥ 1.5 mm) and recruited for the present study. Irregular surface was defined when plaque surface was uneven with high and low fluctuation or plaque with surface ulceration. The irregularity of carotid plaque surface was determined on axial or oblique images alone(single-dimension) and on both axial images and oblique images(multidimensions), separately. Univariate and multivariate logistic regression analyses were performed to calculate the odds ratio(OR) and the corresponding 95% CI of the irregular plaque surface in discriminating the presence of ipsilateral ACI. Results A total of 217 included subjects(mean age: 60.7 ± 10.2 years, 149 men) were recruited and 89(41.0%), 88(40.6%) and 118(54.4%) of them exhibited irregular plaque surface on axial, oblique and multidimensional MR images, respectively. The OR of irregularity of the plaque surface was determined by multidimensional MRI to be 5.88(95% CI: 3.16–10.96, P < 0.001) in discriminating the presence of ipsilateral ACI. Following adjustment for clinical confounding factors, this association remained statistically significant(OR = 5.65, 95% CI: 2.53–12.60, P < 0.001). The analysis included further adjustment for the presence of lipid-rich necrotic core, intraplaque hemorrhage and stenosis and the results included that this association also remained statistically significant(OR = 6.08, 95% CI: 2.52–14.68, P < 0.001). Conclusions The irregular plaque surface was determined by multidimensional MRI as an independent indicator for ipsilateral acute cerebral infarction.

Hemodynamic analysis of intracranial aneurysms using phase-contrast magnetic resonance imaging and computational fluid dynamics

Additional hemodynamic parameters are highly desirable in the clinical management of intracranial aneurysm rupture as static medical images cannot demonstrate the blood flow within aneurysms. There are two ways of obtaining the hemodynamic information-by phase-contrast magnetic resonance imaging (PCMRI) and computational fluid dynamics (CFD). In this paper, we compared PCMRI and CFD in the analysis of a stable patient's specific aneurysm. The results showed that PCMRI and CFD are in good agreement with each other. An additional CFD study of two stable and two ruptured aneurysms revealed that ruptured aneurysms have a higher statistical average blood velocity, wall shear stress, and oscillatory shear index (OSI) within the aneurysm sac compared to those of stable aneurysms. Furthermore, for ruptured aneurysms, the OSI divides the positive and negative wall shear stress divergence at the aneurysm sac.

Magnetic resonance angiography for the primary diagnosis of pulmonary embolism: A review from the international workshop for pulmonary functional imaging

Pulmonary contrast enhanced magnetic resonance angiography(CE-MRA) is useful for the primary diagnosis of pulmonary embolism(PE). Many sites have chosen not to use CE-MRA as a first line of diagnostic tool for PE because of the speed and higher efficacy of computerized tomographic angiography(CTA). In this review, we discuss the strengths and weaknesses of CEMRA and the appropriate imaging scenarios for the primary diagnosis of PE derived from our unique multiinstitutional experience in this area. The optimal patient for this test has a low to intermediate suspicion for PE based on clinical decision rules. Patients in extremis are not candidates for this test. Younger women(< 35 years of age) and patients with iodinated contrast allergies are best served by using this modality We discuss the history of the use of this test, recent technical innovations, artifacts, direct and indirect findings for PE, ancillary findings, and the effectiveness(patient outcomes) of CE-MRA for the exclusion of PE. Current outcomes data shows that CE-MRA and NM V/Q scans are effective alternative tests to CTA for the primary diagnosis of PE.

Parallel variable-density spiral imaging using nonlocal total variation reconstruction

The relatively long scan time is still a bottleneck for both clinical applications and research of magnetic resonance imaging. To reduce the data acquisition time, we propose a novel fast magnetic resonance imaging method based on parallel variable-density spiral acquisition, which combines undersampling optimization and nonlocal total variation reconstruction. The undersampling optimization promotes the incoherence of resultant aliasing artifact via the ＂worst-case＂ residual error metric, and thus accelerates the data acquisition. Moreover, nonlocal total variation reconstruction is utilized to remove such an incoherent aliasing artifact and so improve image quality. The feasibility of the proposed method is demonstrated by both numerical phantom simulation and in vivo experiment. The experimental results show that the proposed method can achieve high acceleration factor and effectively remove an aliasing artifact from data undersampling with well-preserved image details. The image quality is better than that achieved with the total variation method.

A comparison of carotid atherosclerosis in symptomatic patients between 2002-2005 and 2012-2015 cohorts using multi-contrast magnetic resonance vessel wall imaging

OBJECTIVE To compare the morphological and compositional characteristics of carotid plaques in two cohorts(2002−2005 and 2012−2015)of Chinese patients using magnetic resonance vessel wall imaging.METHODS Symptomatic patients with carotid atherosclerotic plaques who underwent carotid vessel wall magnetic resonance imaging between 2002−2005 and 2012−2015 were retrospectively recruited.Plaque morphology[including mean wall area,wall thickness,and maximum normalized wall index(NWI)]and composition[including calcification,intraplaque hemorrhage,and lipid-rich necrotic core(LRNC)]in symptomatic carotid arteries were evaluated and compared between patients in these two time periods.RESULTS A total of 258 patients,including 129 patients in the 2002−2005 cohort and 129 patients in the 2012−2015 cohort,were recruited.Statin use(49.6%vs.32.6%,P=0.004)and hypertension(76.0%vs.62.8%,P=0.015)were significantly more common in the 2012-2015 cohort than in the 2002−2005 cohort.Patients in the 2012−2015 cohort also exhibited significantly low plaque burden parameters(all P<0.05),as well as a lower prevalence(68.2%vs.89.9%,P<0.001)and volume percentages of LRNC(11.2%±14.2%vs.25.7%±17.7%,P<0.001).These differences remained significant after adjustment for clinical factors.The differences in the volume percentages of LRNC also remained significant after an additional adjustment for maximum NWI(P<0.001).CONCLUSIONS Patients in the 2012−2015 cohort had a lower plaque burden and volume percentages of LRNC in symptomatic carotid arteries than those in the 2002−2005 cohort.These findings indicate that carotid plaques in the recent cohort had a lower severity and vulnerability.

Visual resolution under photopic and mesopic conditions in patients with Sjogren's syndrome

AIM:To focus on different visual resolution tasks under photopic and mesopic conditions in Sjogren’s syndrome patients compared to age-matched healthy controls.METHODS:The visual resolution measurements included high and low visual acuities and contrast sensitivity functions.These tests were conducted under photopic and then mesopic conditions.Twenty-one Sjögren’s syndrome patients and 21 aged-matched healthy volunteers completed all the measurements in this study.RESULTS:Sjogren’s syndrome patients have greater impairment in contrast sensitivity than standardized visual acuity.This reduction was significant under the mesopic condition.Also,Sjogren’s syndrome patients treated with pilocarpine suffer more than patients without pilocarpine treatment under low light conditions.CONCLUSION:Sjogren’s syndrome patients shows greater impairment in different visual resolution tasks due to dry eye symptoms.

Computer-aided diagnosis for contrast-enhanced ultrasound in the liver

Computer-aided diagnosis(CAD) has become one of the major research subjects in medical imaging and diagnostic radiology.The basic concept of CAD is to provide computer output as a second opinion to assist radiologists' image interpretations by improving the accuracy and consistency of radiologic diagnosis and also by reducing the image-reading time.To date,research on CAD in ultrasound(US)-based diagnosis has been carried out mostly for breast lesions and has been limited in the fields of gastroenterology and hepatology,with most studies being conducted using B-mode US images.Two CAD schemes with contrast-enhanced US(CEUS) that are used in classifying focal liver lesions(FLLs) as liver metastasis,hemangioma,or three histologically differentiated types of hepatocellular carcinoma(HCC) are introduced in this article:one is based on physicians' subjective pattern classifications(subjective analysis) and the other is a computerized scheme for classification of FLLs(quantitative analysis).Classification accuracies for FLLs for each CAD scheme were 84.8% and 88.5% for metastasis,93.3% and 93.8% for hemangioma,and 98.6% and 86.9% for all HCCs,respectively.In addition,the classification accuracies for histologic differentiation of HCCs were 65.2% and 79.2% for well-differentiated HCCs,41.7% and 50.0% for moderately differentiated HCCs,and 80.0% and 77.8% for poorly differentiated HCCs,respectively.There are a number of issues concerning the clinical application of CAD for CEUS,however,it is likely that CAD for CEUS of the liver will make great progress in the future.

cAMP/PKA pathway and mitochondrial protection in oxidative stress-induced optic nerve head astrocytes

Oxidative stress and cyclic adenosine 3′,5′-monophosphate(cAMP)/protein kinase A(PKA)pathway in the optic nerve head astrocytes:Glaucoma is a leading cause of blindness worldwide in individuals 60 years of age and older.Despite the widely appreciated disease relevance of structural and functional abnormalities of astrocyte in the optic nerve head(ONH)that is associated with retinal ganglion cell(RGC)axon degeneration,the molecular mechanisms underlying astrocyte dysfunction in glaucomatous ONH degeneration are poorly understood.Oxidative stress is strongly linked to glaucoma pathogenesis,and astrocytes are the responsible cell type that is mostly related to oxidative stress and glaucomatous ONH degeneration.

Association between antiplatelet medication and cerebral microbleeds in stroke-free population

BACKGROUND Cerebral microbleeds(CMBs)may increase the risk of future intracerebral hemorrhage and ischemic stroke.However,It is unclear whether antiplatelet medication is associated with CMBs.This study aimed to investigate the association between antiplatelet medication and CMBs in a community-based stroke-free population.METHODS In this cross-sectional study,stroke-free participants aged 18-85 years were recruited from a community in Beijing,China.Demographic,clinical,and antiplatelet medication data were collected through a questionnaire,and all participants underwent blood tests and brain magnetic resonance imaging at 3.0T.The presence,count,and location of CMBs were evaluated using susceptibility-weighted imaging.The association between antiplatelet medication and the presence of CMBs was analyzed using multivariable logistic regression.The associations between antiplatelet medication and CMBs by location(lobar,deep brain or infratentorial,and mixed regions)were also analyzed using multinomial logistic regression.A linear regression analysis was conducted to determine the association between antiplatelet medication and the log-transformed number of CMBs.RESULTS Of the 544 participants(mean age:58.65±13.66 years,217 males),119 participants(21.88%)had CMBs,and 64 participants(11.76%)used antiplatelet medication.Antiplatelet medication was found to be associated with CMBs at any location[odds ratio(OR)=2.39,95%CI:1.24-4.58]and lobar region(OR=2.83,95%CI:1.36-5.86),but not with the number of CMBs(β=0.14,95%CI:-0.21-0.48).Among antiplatelet medications,aspirin use was found to be associated with any CMB(OR=3.17,95%CI:1.49-6.72)and lobar CMBs(OR=3.61,95%CI:1.57-8.26).CONCLUSIONS Antiplatelet medication was associated with CMBs in stroke-free participants,particularly lobar CMBs.Among antiplatelet medications,aspirin use was associated with any CMB and lobar CMBs.Our findings suggest that it might be essential to optimize the management of antiplatelet medication in the stroke-free population with a higher burden of vascular risk factors to reduce the potential risk of CMBs.

Association of atherosclerotic plaque features with collateral circulation status in elderly patients with chronic carotid stenosis

Objective To determine the association of carotid plaque features with collateral circulation status in elderly patients with moderate to severe carotid stenosis.Methods Elderly patients(>60 years)with moderate to severe carotid stenosis were recruited and categorized into good and poor collateral circulation groups,and underwent magnetic resonance imaging and computed tomography imaging.The carotid plaque features including lipid-rich necrotic core,intraplaque hemorrhage,calcification,and fibrous cap rupture(FCR)were evaluated,and maximum wall thickness,normalized wall index(NWI),and luminal stenosis were measured.The association between these variables and collateral circulation status was analyzed.Results Of the 97 patients(78 males,mean age:69.0±6.1 years),19(19.6%)had poor collaterals.The poor collateral group had a significantly higher NWI(93.7%±5.0%vs.89.0%±7.9%,P=0.011),a greater extent of stenosis(80.0%±11.4%vs.75.3%±9.4%,P=0.036)and FCR(84.2%vs.55.1%,P=0.020)compared with good collateral group.Carotid NWI(OR=3.83,95%CI:1.36–10.82,P=0.011)and more FCR(OR=6.77,95%CI:1.35–33.85,P=0.020)were associated with poor collateral circulation after adjustment for the confounding factors.The combination of NWI,FCR,systolic blood pressure,and triglycerides had the highest area-under-the-curve(AUC=0.85)for detection of poor collaterals.Conclusions Carotid plaque features,specifically NWI and FCR,are independently associated with poor collateral circulation,and the combination of carotid plaque features and traditional risk factors has a stronger predictive value for poor collateral circulation than plaque features alone.

Reductive Amination with [¹¹C]Formaldehyde: A Versatile Approach to Radiomethylation of Amines

Carbon-11 radiolabeled amines constitute a very important class of radioligands that are widely used for positron emission tomography (PET) imaging. Radiolabeling of amines is often achieved through radiomethylation using [11C]CH3I or [11C]CH3OTf under basic conditions in a strictly anhydrous environment. Functional groups such as hydroxyl and carboxyl groups that are often present in the molecules are normally base sensitive and require protection and deprotection, which substantially prolongs and complicates the radiolabeling process. Here we report a versatile approach to a series of C-11 radiolabeled amines prepared through reductive amination using [11C]formaldehyde. Using a variety of substrates bearing different functional groups, we demonstrate the general utility of this method. In contrast to conventional radiomethylation methods, the reductive amination using [11C]formaldehyde can be carried out in an aqueous environment relatively quickly without the need of protection of base-sensitive functional groups.

Classification of Emphysema Subtypes: Comparative Assessment of Local Binary Patterns and Related Texture Features

The purpose of this study was to assess usefulness of local binary patterns (LBP) and related texture features, namely completed local binary patterns (CLBP) and local ternary patterns (LTP), for the classification of emphysema subtypes on low-dose CT images. Fifty patients (34 men and 16 women;age, 67.5 ± 10.1 years) who underwent low-dose CT (60 mAs) were included. They were comprised of 17 never smokers, 13 smokers without COPD, and 20 smokers with COPD. By consensus reading of low-dose CT images from these patients, two radiologists selected 3681 nonoverlapping regions of interest (ROIs) and annotated them as one of the following three classes: normal tissue, centrilobular emphysema, and paraseptal emphysema. From these ROIs, histogram of CT densities, LBP, CLBP, and LTP were calculated, and the 3 types of texture histograms were concatenated with the CT density histogram. These 3 types of histograms (referred to as combined LBP, combined CLBP, and combined LTP) were used to classify ROI using linear support vector machine. For each type of the combined histogram, the accuracy of classification was determined by patient-based 10-fold cross validation. The best accuracy of combined LBP, combined CLBP, and combined LTP were 81.36%, 82.99%, and 83.29%, respectively. Compared to the classification accuracies obtained with combined LBP, those with combined LTP or combined CLBP were consistently improved. In conclusion, the results of this study suggest that, on low-dose CT, LTP and CLBP were more useful for the classification of emphysema subtypes than LBP.

Tumor Segmentation on ¹⁸F FDG-PET Images Using Graph Cut and Local Spatial Information

The purpose of this study was to develop methodology to segment tumors on 18F-fluorodeoxyg- lucose (FDG) positron emission tomography (PET) images. Sixty-four metastatic bone tumors were included. Graph cut was used for tumor segmentation, with segmentation energy divided into unary and pairwise terms. Locally connected conditional random fields (LCRF) were proposed for the pairwise term. In LCRF, three-dimensional cubic window with length L was set for each voxel, and voxels within the window were considered for the pairwise term. Three other types of segmentation were applied: region-growing based on 35%, 40%, and 45% of the tumor maximum standardized uptake value (RG35, RG40, and RG45, respectively), SLIC superpixels (SS), and region-based active contour models (AC). To validate the tumor segmentation accuracy, dice similarity coefficients (DSC) were calculated between the result of each technique and manual segmentation. Differences in DSC were tested using the Wilcoxon signed-rank test. Mean DSCs for LCRF at L = 3, 5, 7, and 9 were 0.784, 0.801, 0.809, and 0.812, respectively. Mean DSCs for the other techniques were: RG35, 0.633;RG40, 0.675;RG45, 0.689;SS, 0.709;and AC, 0.758. The DSC differences between LCRF and other techniques were statistically significant (p < 0.05). Tumor segmentation was reliably performed with LCRF.

Mitigating the impact of mechanisms causing neuronal degeneration

Primary and secondary neurodegeneration is a pathological hallmark of numerous central nervous system(CNS)disorders.Although many mechanisms leading to neurodegeneration are well understood,previous approaches aiming at providing protection from neurodegeneration were often futile.A potential explanation may be that recent research discovered additional pathomechanisms leading to neurodegeneration.Thus,simply targeting single neurodegenerative mechanisms may only have minor therapeutic impact.Addressing multiple neurodegenerative mechanisms may be a more viable strategy.Moreover,the restoration of lost brain tissue turned out to be a very complex endeavor.1 Despite making some initial progress with the use of biocompatible scaffolds and hydrogels.

Differences in left and right carotid plaque vulnerability in patients with bilateral carotid plaques:a CARE-II study

Background and purpose Atherosclerosis is a very complex process influenced by various systemic and local factors.Therefore,in patients with bilateral carotid plaques(BCPs),there may be differences in carotid plaque vulnerability between the sides.We aimed to investigate the differences in BCP characteristics in patients with BCPs using magnetic resonance vessel wall imaging(MR-VWI).Methods Participants with BCPs were selected for subanalysis from a multicentre study of Chinese Atherosclerosis Risk Evaluation II.We measured carotid plaque burden,identified each plaque component and measured their volume or area bilaterally on MR-VWI.Paired comparisons of the burden and components of BCPs were performed.Results In all,540 patients with BCPs were eligible for analysis.Compared with the right carotid artery(CA),larger mean lumen area(p<0.001),larger mean wall area(p=0.025),larger mean total vessel area(p<0.001)and smaller normalised wall index(p=0.006)were found in the left CA.Regarding plaque components,only the prevalence of lipid-rich necrotic core(LRNC)in the left CA was higher(p=0.026).For patients with a vulnerable plaque component coexisting on both sides,only the intraplaque haemorrhage(IPH)volume(p=0.011)was significantly greater in the left CA than in the right CA.Conclusions There were asymmetries in plaque growth and evolution between BCPs.The left carotid plaques were more likely to have larger plaque burden,higher prevalence of LRNC and greater IPH volume,which may contribute to the lateralisation of ischaemic stroke in the cerebral hemispheres.

Mesenchymal stem cell-derived exosomes:Shaping the next era of stroke treatment

Exosome-based treatments are gaining traction as a viable approach to addressing the various issues faced by an ischemic stroke.These extracellular vesicles,mainly produced by mesenchymal stem cells,exhibit many properties with substantial therapeutic potential.Exosomes are particularly appealing for stroke therapy because of their low immunogenicity,effective cargo transport,and ability to cross the blood–brain barrier.Their diverse effects include neuroprotection,angiogenesis stimulation,inflammatory response modulation,and cell death pathway attenuation,synergistically promoting neuronal survival,tissue regeneration,and functional recovery.Exosomes also show potential as diagnostic indicators for early stroke identification and customized treatment options.Despite these promising qualities,current exosome-based therapeutics have some limitations.The heterogeneity of exosome release among cell types,difficulty in standardization and isolation techniques,and complications linked to dosage and targeted administration necessitates extensive investigation.It is critical to thoroughly understand exosomal processes and their complicated interactions within the cellular milieu.To improve the practicality and efficacy of exosome-based medicines,research efforts must focus on improving production processes,developing robust evaluation criteria,and developing large-scale isolation techniques.Altogether,exosomes’multifunctional properties offer a new route for transforming stroke treatment and significantly improving patient outcomes.

Association between coexisting intracranial artery and extracranial carotid artery atherosclerotic diseases and ipsilateral cerebral infarction: a Chinese Atherosclerosis Risk Evaluation (CARE- II) study

Background To evaluate the association between coexisting intracranial and extracranial carotid artery atherosclerotic diseases and ipsilateral acute cerebral infarct(ACI)in symptomatic patients by using magnetic resonance(MR)vessel wall imaging.Methods Symptomatic patients were recruited from a cross-sectional,multicentre study of Chinese Atherosclerosis Risk Evaluation(CARE-II).All patients underwent MR imaging for extracranial carotid arterial wall,intracranial artery and brain.Coexisting intracranial stenosis≥50%and extracranial carotid artery mean wall thickness(MWT)≥1 mm and plaque compositions at the same side were evaluated and the ipsilateral ACI was identified.The association between coexisting atherosclerotic diseases and ACI was evaluated using logistic regression.Results 351 patients were recruited.Patients with ipsilateral ACI had significantly greater prevalence of coexisting intracranial stenosis≥50%and carotid MWT≥1 mm(20.5%vs 4.9%,p<0.001),calcification(15.1%vs 4.4%,p=0.001)and lipid-rich necrotic core(LRNC)(19.2%vs 7.8%,p=0.002)compared with those without.Coexisting intracranial artery stenosis≥50%and carotid MWT≥1 mm(OR 5.043,95%CI 2.378 to 10.694;p<0.001),calcification(OR 3.864,95%CI 1.723 to 8.664;p=0.001)and LRNC(OR 2.803,95%CI 1.455 to 5.401;p=0.002)were significantly associated with ipsilateral ACI.After adjusting for confounding factors,the aforementioned associations remained statistically significant(intracranial stenosis≥50%coexisting with carotid MWT≥1 mm:OR 4.313,95%CI 1.937 to 9.601,p<0.001;calcification:OR 3.606,95%CI 1.513 to 8.593,p=0.004;LRNC:OR 2.358,95%CI 1.166 to 4.769,p=0.017).Conclusions Coexistence of intracranial artery severe stenosis and extracranial carotid artery large burden and intraplaque components of calcification and LRNC are independently associated with ipsilateral ACI.Trial registration number https://www.clinicaltrials.gov/.Unique identifier:NCT02017756.

Associations between haemodynamics and wall enhancement of intracranial aneurysm

Background and purpose Previous studies have reported about inflammation processes(IPs)that play important roles in aneurysm formation and rupture,which could be driven by blood flow.IPs can be identified using aneurysmal wall enhancement(AWE)on high-resolution black-blood MRI(BB-MRI)and blood flow haemodynamics can be demonstrated by four-dimensional-flow MRI(4D-flow MRI).Thus,this study investigated the associations between AWE and haemodynamics in unruptured intracranial aneurysms(IA)by combining 4D-flow MRI and high-resolution BB-MRI.Materials and methods Between April 2014 and October 2017,48 patients with 49 unruptured IA who underwent both 4D-flow MRI and high-resolution BB-MRI were retrospectively included in this study.The haemodynamic parameters demonstrated using 4D-flow MRI were compared between different AWE patterns using the Kruskal-Wallis test and ordinal regression.Results The results of Kruskal-Wallis test showed that the average wall shear stress in the IA(WSSavg-IA),maximum through-plane velocity in the adjacent parent artery,inflow jet patterns and the average vorticity in IA(vorticityavg-IA)were significantly associated with the AWE patterns.Ordinal regression analysis identified WSSavg-IA(p=0.002)and vorticityavg-IA(p=0.033)as independent predictors of AWE patterns.Conclusion A low WSS and low average vorticity were independently associated with a high AWE grade for IAs larger than 4 mm.Therefore,WSS and average vorticity could predict AWE and circumferential AWE.

Association between fluid-attenuated inversion recovery vascular hyperintensity and outcome varies with different lesion patterns in patients with intravenous thrombolysis

Background and purpose To evaluate relationship between fluid-attenuated inversion recovery vascular hyperintensity(FVH)after intravenous thrombolysis and outcomes in different lesion patterns on diffusion-weighted imaging(DWI).Methods Patients with severe internal carotid or intracranial artery stenosis who received intravenous thrombolysis from March 2012 to April 2019 were analysed.They were divided into four groups by DWI lesion patterns:border-zone infarct(BZ group),multiple lesions infarct(ML group),large territory infarct(LT group),and single cortical or subcortical lesion infarct(SL group).Logistic regression was performed to identify risk factors for outcome(unfavourable outcome,modified Rankin Scale(mRS)≥2;poor outcome,mRS≥3).Results Finally,203 participants(63.3±10.2 years old;BZ group,n=72;ML group,n=64;LT group,n=37;SL group,n=30)from 1190 patient cohorts were analysed.After adjusting for confounding factors,FVH(+)was associated with unfavourable outcome in total group(OR 3.02;95%CI 1.49 to 6.13;p=0.002),BZ group(OR 4.22;95%CI 1.25 to 14.25;p=0.021)and ML group(OR 5.44;95%CI 1.41 to 20.92;p=0.014)patients.FVH(+)was associated with poor outcome in total group(OR 2.25;95%CI 1.01 to 4.97;p=0.046),BZ group(OR 5.52;95%CI 0.98 to 31.07;p=0.053)and ML group(OR 4.09;95%CI 1.04 to 16.16;p=0.045)patients,which was marginal significance.FVH(+)was not associated with unfavourable or poor outcome in LT and SL groups.Conclusion This study suggests that association between FVH and outcome varies with different lesion patterns on DWI.The presence of FVH after intravenous thrombolysis may help to identify patients who require close observations in the hospitalisation in patients with border-zone and multiple lesion infarcts.

Differences in atheroma between Caucasian and Asian subjects with anterior stroke:A vessel wall MRI study

Background and purpose While extracranial carotid artery stenosis is more common among Caucasians and intracranial artery stenosis is more common among Asians,the differences in atherosclerotic plaque characteristics have not yet been extensively examined.We sought to investigate plaque location and characteristics within extracranial carotid and intracranial arteries in symptomatic Caucasians and Chinese using vessel wall MRI.Methods Subjects with recent anterior circulation ischaemic stroke were recruited and imaged at two sites in the USA and China using similar protocols.Both extracranial carotid and intracranial arteries were reviewed to determine plaque location and characteristics.Results The prevalence of extracranial carotid plaque in Caucasians and Chinese was 73.1%and 49.1%,respectively(p=0.055).Prevalence of intracranial plaque was 38.5%and 69.1%in Caucasians and Chinese,respectively(p=0.02).Furthermore,42% of Caucasians and 16%of Chinese had high-risk plaque(HRP)features(intraplaque haemorrhage,luminal surface disruption)in the extracranial carotid artery(p=0.03).The prevalence of HRP features in intracranial arteries was not significantly different between the two cohorts(4%vs 11%;p=0.42).Conclusions Differences in the location and characteristics of cerebrovascular atherosclerosis were identified by vessel wall MRI in US Caucasian and Chinese subjects with recent anterior circulation ischaemic stroke.Extracranial carotid plaques with HRP features were more common in Caucasians.Intracranial plaques were more common in Chinese subjects,but no significant difference between the two cohorts in intracranial HRP prevalence was found.Larger studies using vessel wall imaging to investigate racial differences in cerebrovascular disease may inform underlying mechanisms of HRP development and may ultimately help guide appropriate therapy.