Vessel Wall Magnetic Resonance Imaging Research Articles

Histological Validation of 3D Variable Flip Angle TSE Multi-Contrast Magnetic Resonance Vessel Wall Imaging in Characterizing Carotid Vulnerable Atherosclerotic Plaques

BackgroundAccurate assessment of the vulnerability of carotid atherosclerotic plaques is crucial for stroke prevention. The three-dimensional (3D) magnetic resonance (MR) vessel wall imaging (VWI) has been increasingly employed to evaluate carotid plaques due to its extensive coverage and isotropic high spatial resolution. However, the accuracy of such technique lacks validation by histology. ObjectiveThis study aims to validate the accuracy of 3D multi-contrast MR VWI used variable-flip-angle (VFA) and turbo spin echo (TSE) readout in identifying vulnerable carotid plaques, using histological analysis as a reference. MethodsTwenty-one male patients (mean age: 64.4 ± 7.2 years) scheduled for carotid endarterectomy (CEA) were recruited for this study. All patients underwent carotid multi-contrast MR VWI, including 3D T1- and T2-weighted variable flip angle-based turbo spin echo (VFA-TSE) sequences, as well as 3D time of flight (TOF) MR angiography (MRA), using a 3.0T MR system. Histological processing was performed for carotid plaque specimens. The presence or absence, along with the area measurements, of lipid-rich necrotic core (LRNC), intraplaque hemorrhage (IPH), and calcifications (CA) were independently evaluated on both MR images and histological sections. Cohen’s kappa (κ) analysis was utilized to determine the agreement between 3D multi-contrast MR VWI and histology in identifying carotid plaque compositions before and after excluding compositions bellow certain size threshold. Spearman’s correlation analysis was also conducted to assess the agreement in quantifying plaque compositions. ResultsA total of 81 slices of MR images were successfully matched with histological sections. Moderate to almost perfect agreements were observed between 3D MR VWI and histology in the identification of LRNC (κ: 0.85 and 0.89), IPH (κ: 0.65 and 0.69), and CA (κ: 0.46 and 0.62) before and after excluding compositions smaller than 0.79 mm2. Strong to very strong correlations were found in the quantification of plaque compositions including LRNC (r=0.88), IPH (r=0.80), and CA (r=0.74) between MR imaging and histology. ConclusionThe 3D VFA-TSE multi-contrast MR VWI is capable of accurately characterizing vulnerable carotid atherosclerotic plaques.

Comparison of computer-aided quantitative measurement and physician visual assessment in the evaluation of intracranial atherosclerotic stenosis: a vessel wall magnetic resonance imaging study.

Intracranial atherosclerotic stenosis is a leading cause of ischemic stroke in China. Accurate assessment of intracranial atherosclerotic stenosis through imaging techniques is crucial for guiding therapeutic interventions and prognostic stratification. Vessel wall magnetic resonance imaging (VWMRI) has emerged as a reliable method for evaluating intracranial arterial vessels. With the advancement of technology, computer-aided quantitative measurement (CAQM) is increasingly used in imaging assessment. This study aimed to compare physician visual assessment (PVA) with CAQM in the VWMRI evaluation of intracranial atherosclerotic stenosis. This retrospective cross-sectional study consecutively enrolled patients diagnosed with intracranial atherosclerotic stenosis through imaging examinations at the Fourth Affiliated Hospital of China Medical University from December 2018 to December 2023. Clinical data were collected for analysis. Two radiologists independently and separately conducted CAQM and PVA on the VWMRI images of intracranial atherosclerotic stenosis patients. The imaging features evaluated encompassed stenosis severity, vessel wall remodeling, vessel wall thickening patterns, fibrous cap characteristics, lipid core ratio, and plaque enhancement degree. The study further assessed the discrepancies and concordance between the assessment results obtained from the two methods using paired sample t-tests, Wilcoxon signed-rank tests, and Cohen's kappa coefficient analysis. This study enrolled a total of 589 patients. The PVA time was shorter than CAQM (12.02±3.63 vs. 20.48±6.50 min). However, compared with digital subtraction angiography, the CAQM had a better area under the curve (0.88) than the PVA (0.80) in assessing luminal stenosis degree. The proportions of vessel wall remodeling (227/38.5%) and plaque surface irregularity (127/21.6%) evaluated by PVA were both lower than those by CAQM (438/74.4%, 171/29.0%). Meanwhile, no statistically significant differences were found in the patterns of wall thickening (P=0.12/0.39) and the proportion of plaque lipid core (P=0.65 and P=0.27), with good agreement between the two methods (K=0.67/0.85, K=0.97/0.94). While there were no statistical differences in the assessment of plaque enhancement degree in specific arteries (middle cerebral artery and basilar artery) (n=77/36, P=0.08/0.21), an overall statistical difference was observed (n=113, P=0.03). Additionally, there was poor agreement in assessing plaque enhancement degree, with Cohen's kappa values of 0.13 (-0.05 to 0.32) and 0.16 (-0.06 to 0.39). This study revealed disparities between PVA and CAQM in the evaluation of intracranial atherosclerotic stenosis of VWMRI. CAQM is recommended for assessing stenosis degree, vessel wall remodeling, and fibrous cap characteristics. However, PVA is suggested to assess wall thickening patterns and lipid core ratio to expedite diagnosis. Further research is needed to validate CAQM's superiority in evaluating plaque enhancement degrees.

Predicting outcomes of unruptured intracranial artery dissection with clear symptoms onset using clinical and radiological features

We investigated the clinical and radiologic predictors of unruptured symptomatic intracranial artery dissection (IAD) outcomes. Unruptured symptomatic IAD patients who underwent vessel wall magnetic resonance imaging (VW-MRI) and time-of-flight magnetic resonance angiography (TOF-MRA) within 1 month after symptom onset, followed for over 12 months were included. Baseline features predicting the clinical outcome of recurrent symptoms and radiologic outcomes of aneurysmal dilatation and occlusion were analyzed using logistic regression analysis. The Kaplan–Meier method calculated the median time to morphological stability. Patients with aneurysmal dilatation were categorized into progressive and non-progressive enlargement subgroups. Seventy-three IADs from 65 patients were included. All patients showed benign clinical course (mRS 0–1). No baseline features were predictive of recurrent symptoms. Aneurysmal dilatation was associated with increased outer diameter in baseline VW-MRI (OR, 23.15; 95% CI, 3.78–141.75, P < 0.001) and TOF-MRA (OR, 10.81; 95% CI, 2.16–53.99, P = 0.004). Occlusion was inversely associated with preserved patency in baseline VW-MRI (OR, 0.1; 95% CI, 0.01–0.74, P = 0.024) and TOF-MRA (OR, 0.14; 95% CI, 0.02–0.98; P = 0.048). The median time to morphological stability was 3.9 months (95% CI, 3.16–5.5). While baseline features did not significantly differ between aneurysmal dilatation subgroups, follow-up imaging revealed significant differences in remodeling index, normalized wall index, relative signal intensity of intramural hematoma, and presence of onion-skin appearance and intramural hematoma (all P < 0.05). Our findings suggest that while unruptured IAD presents a benign clinical outcome, follow-up imaging may be necessary to monitor the progressive enlargement of aneurysmal dilatation.

Vessel wall MRI in giant cell arteritis: standardized protocol and scoring approach developed by an international working group.

There are an increasing number of centers performing research on high-resolution vessel wall magnetic resonance imaging (VW-MRI) in giant cell arteritis (GCA). However, harmonized approaches to VW-MRI in GCA are lacking and are essential to performing multicentre studies. Using a data-driven, consensus-based approach, an international expert group developed a standardized MRI protocol and scoring system to advance multi-centered research in cranial GCA. A targeted literature review of VW-MRI in cranial GCA was conducted. A working group comprised of radiologists, rheumatologists, and ophthalmologists with expertise in VW-MRI and GCA reviewed the results of the literature search, presented relevant data and images from their respective centers, and then reached consensus on recommendations related to key MRI structures, MRI sequences, scoring system, and other important considerations. A total of 21 relevant articles were identified and reviewed. Based on published literature, structures to be evaluated on MRI were categorized based on anatomic location (extradural cranial, intradural cranial, and orbits) and prioritization (core vs elective). Essential and elective sequences to comprehensively image cranial and orbital structures while minimizing scan time were determined along with scoring systems to grade contrast enhancement. This report describes a standardized approach to facilitate research of VW-MRI in cranial GCA that is the result of a multi-disciplinary, international collaboration of experts in VW-MRI and/or GCA.

Intracranial Atherosclerotic Disease and Incident Dementia: The ARIC Study (Atherosclerosis Risk in Communities).

Studies of the neurovascular contribution to dementia have largely focused on cerebral small vessel disease (CSVD), but the role of intracranial atherosclerotic disease (ICAD) remains unknown in the general population. The objective of this study was to determine the risk of incident dementia from ICAD after adjusting for CSVD and cardiovascular risk factors in a US community-based cohort. We acquired brain magnetic resonance imaging examinations from 2011 through 2013 in 1980 Black and White participants in the ARIC study (Atherosclerosis Risk in Communities), a prospective cohort conducted in 4 US communities. Magnetic resonance imaging examinations included high-resolution vessel wall magnetic resonance imaging and magnetic resonance angiography to identify ICAD. Of these participants, 1590 without dementia, without missing covariates, and with adequate magnetic resonance image quality were followed through 2019 for incident dementia. Associations between ICAD and incident dementia were assessed using Cox proportional hazard ratios adjusted for CSVD (characterized by white matter hyperintensities, lacunar infarctions, and microhemorrhages), APOE4 genotype (apolipoprotein E gene ε4), and cardiovascular risk factors. The mean age (SD) of study participants was 77.4 (5.2) years. ICAD was detected in 34.6% of participants. After a median follow-up of 5.6 years, 286 participants developed dementia. Compared with participants without ICAD, the fully adjusted hazard ratios (95% CIs) for incident dementia in participants with any ICAD, with ICAD only causing stenosis ≤50%, and with ICAD causing stenosis >50% in ≥1 vessel were 1.57 (1.17-2.11), 1.41 (1.02-1.95), and 1.94 (1.32-2.84), respectively. ICAD was associated with dementia even among participants with low white matter hyperintensities burden, a marker of CSVD. ICAD was associated with an increased risk of incident dementia, independent of CSVD, APOE4 genotype, and cardiovascular risk factors. The increased risk of dementia was evident even among participants with low CSVD burden, a group less likely to be affected by vascular dementia, and in participants with ICAD causing only low-grade stenosis. Our results suggest that ICAD may partially mediate the effect that cardiovascular risk factors have on the brain leading to dementia. Both ICAD and CSVD must be considered to understand the vascular contributions to cognitive decline.

Does it stable? Intracranial aneurysm wall enhancement might be the warning signals: a meta-analysis of observational studies.

Magnetic resonance vessel wall imaging (MR-VWI) is an emerging imaging technology used to assess the progressive risk of unruptured intracranial aneurysms (UIAs). Unlike the standard evaluation model, MR-VWI is still debatable. This study aims to further define the potential relationship between aneurysm wall enhancement (AWE) and aneurysm stability. Using "intracranial aneurysm", "magnetic resonance", and "enhancement" as keywords, relevant studies were systematically searched in PubMed, Embase, and Cochrane, and the qualified studies were enrolled for further analysis. There were 13 case-control studies, 4 cohort studies, and 2,678 cases of intracranial aneurysms included in the meta-analysis. It was shown that AWE was correlated with intracranial aneurysm rupture (OR = 35.90, 95% CI: 15.58 to 82.75, p < 0.001), growth (OR = 6.69, 95% CI: 2.69 to 16.63, p < 0.001), and presence of symptoms (OR = 14.46, 95% CI: 9.07 to 23.05, p < 0.001). This finding had a high diagnostic value, but the correlation was probably not independent of aneurysm size. The pooled relative risks of the follow-up studies revealed that the risk of UIA progression was approximately 3.33 times higher with AWE than without AWE (RR = 3.33, 95% CI: 2.33 to 4.78, p < 0.001). In addition, the pooled results demonstrated that quantitative indices of VWI enhancement were equally linked with aneurysm stability (OR = 19.61, 95% CI: 10.63 to 36.17, p < 0.001). AWE is an effective imaging method to assess the stability of UIAs, and it can be a marker for the prophylactic treatment of small unruptured intracranial aneurysms in the future, which remains to be validated by prospective studies with large samples.

Intracranial vasculopathy with MR vessel wall imaging: a case series.

Conventional luminal imaging, often the first line investigation, has helped physicians in diagnosing countless patients with cerebrovascular disease but regrettably, it offers little diagnostic clues in patients with challenging vasculopathy, which the latter often requires invasive histopathological diagnosis. In past decade, MR vessel wall imaging has quickly emerged as a non-invasive modality that greatly enhances radiologists' capability of differentiating underlying aetiology. Not only it minimizes surgical trauma to patients, but also provide timely and accurate diagnosis for physicians to offer prompt appropriate treatment and avoid devastating outcomes. Tuen Mun Hospital, the neuroscience centre serving more than 1.3 million population in New Territories, Hong Kong, has been the pioneer in optimizing this novel modality within the district. In this article, we hope to share few interesting cases in our centre on how we utilize its advantage in solving some challenging cases. We would also discuss some common imaging pitfalls and tips on interpretation.

Plaque enhancement of middle cerebral artery and pre-stroke diet are associated with prognosis of subacute ischemic stroke: A prospective high-resolution MR vessel wall imaging study

ObjectivesTo explore the value of middle cerebral artery (MCA) plaque characteristics in predicting the outcomes of subacute ischemic stroke and the incremental value of the previous diet on predictive performance. MethodsOne hundred and thirty-seven subacute ischemic stroke patients attributed to MCA plaques were included and analyzed in this prospective study. The National Institute of Health Stroke Scale (NIHSS) score, Mediterranean Diet Adherence Screener (MEDAS) score, and other clinical data were assessed. The plaque area, degree of stenosis, plaque burden, enhancement ratio, remodeling type, and intraplaque hemorrhage were measured using high-resolution MR vessel wall imaging (HR-VWI). Multivariable logistic regression analysis and receiver operating characteristic curve analysis were performed to assess the predictive performance of clinical and plaque characteristics for subacute ischemic stroke outcomes at 3 months. ResultsPatients with poor outcomes exhibited high NIHSS scores, and low MEDAS scores (P<0.001). Plaque burden, enhancement ratio, and degree of stenosis were significantly higher in patients with poor outcomes (P<0.001). Multivariate analyses further indicated that NIHSS score (P=0.001), MEDAS score (P=0.013), and enhancement ratio (P=0.011) were independent predictors of subacute ischemic stroke outcomes. The three models’ area under the curve (AUC) values were 0.811, 0.844, and 0.794. Combining these three factors resulted in an AUC of 0.908 (P<0.001). ConclusionsThe combination of NIHSS score, MEDAS score, and enhancement ratio showed significant superiority in the prognostic evaluation of subacute ischemic stroke. Clinical data combined with plaque characteristics improves the accuracy of 3-month outcome prediction on subacute ischemic stroke.

Design of the “EAST” strategy in patients with asymptomatic intracranial atherosclerotic stenosis

IntroductionIntracranial atherosclerotic stenosis (ICAS) is one of the most common causes of stroke worldwide and confers a high risk of stroke recurrence, despite aggressive medical therapy. Asymptomatic ICAS (aICAS) is a frequent finding on neuroimaging, and it’s an independent risk factor for future stroke. Alirocumab is a monoclonal antibody that inhibits proprotein convertase subtilisin-kexin type 9 (PCSK9) and effectively lower low-density lipoprotein cholesterol levels. We hypothesize that extra alirocumab in addition to statin therapy (EAST) could stabilize intracranial plaques in patients with aICAS. Methods and analysisIn this prospective, randomized, open-label, blinded end-point study, we will use high-resolution vessel-wall magnetic resonance imaging (HR-vwMRI) to evaluate the efficacy and safety of alirocumab in patients with asymptomatic ICAS. Eighty patients with aICAS (50 %-99 %) caused by unstable plaques will be assigned to the arm of alirocumab plus statin therapy, or the arm of statin therapy in a 1:1 ratio. Patients will undergo HR-vwMRI at recruitment and after 6 months. The primary outcome is changes in plaque features evaluated by HR-vwMRI after 6 months’ treatment. This trial is being conducted at the first affiliated hospital of Nanjing medical university, China. Ethics and disseminationThe study has been approved by the Ethics Committee of the First Affiliated Hospital of Nanjing Medical University. Written informed consents will be obtained from all participants. Study results will be published as peer-reviewed articles. Trial registration numberClinicalTrials.gov, Identifier: NCT06080256.

The relationship between intracranial atherosclerosis and white matter hyperintensity in ischemic stroke patients: a retrospective cross-sectional study using high-resolution magnetic resonance vessel wall imaging.

Both intracranial atherosclerosis and white matter hyperintensity (WMH) are prevalent among the stroke population. However, the relationship between intracranial atherosclerosis and WMH has not been fully elucidated. Therefore, the aim of this study was to investigate the relationship between the characteristics of intracranial atherosclerotic plaques and the severity of WMH in patients with ischemic stroke using high-resolution magnetic resonance vessel wall imaging. Patients hospitalized with ischemic stroke and concurrent intracranial atherosclerosis at Beijing Tsinghua Changgung Hospital, a tertiary comprehensive stroke center, who underwent high-resolution magnetic resonance vessel wall imaging and conventional brain magnetic resonance imaging were continuously recruited from January 2018 to December 2018. Both intracranial plaque characteristics (plaque number, maximum wall thickness, luminal stenosis, T1 hyperintensity, and plaque length) and WMH severity (Fazekas score and volume) were evaluated. Spearman correlation or point-biserial correlation analysis was used to determine the association between clinical characteristics and WMH volume. The independent association between intracranial plaque characteristics and the severity as well as WMH score was analyzed using logistic regression. The associations of intracranial plaque characteristics with total white matter hyperintensity (TWMH) volume, periventricular white matter hyperintensity (PWMH) volume and deep white matter hyperintensity (DWMH) volume were determined using multilevel mixed-effects linear regression. A total of 159 subjects (mean age: 64.0±12.5 years; 103 males) were included into analysis. Spearman correlation analysis indicated that age was associated with TWMH volume (r=0.529, P<0.001), PWMH volume (r=0.523, P<0.001) and DWMH volume (r=0.515, P<0.001). Point-biserial correlation analysis indicated that smoking (r=-0.183, P=0.021) and hypertension (r=0.159, P=0.045) were associated with DWMH volume. After adjusting for confounding factors, logistic regression analysis showed plaque number was significantly associated with the presence of severe WMH [odds ratio (OR), 1.590; 95% CI, 1.241-2.035, P<0.001], PWMH score of 3 (OR, 1.726; 95% CI, 1.074-2.775, P=0.024), and DWMH score of 2 (OR, 1.561; 95% CI, 1.150-2.118, P=0.004). Intracranial artery luminal stenosis was associated with presence of severe WMH (OR, 1.032; 95% CI, 1.002-1.064, P=0.039) and PWMH score of 2 (OR, 1.057; 95% CI, 1.008-1.109, P=0.023). Multilevel mixed-effects linear regression analysis showed that plaque number was associated with DWMH volume (β=0.128; 95% CI, 0.016-0.240; P=0.026) after adjusted for age and sex. In ischemic stroke patients, intracranial atherosclerotic plaque characteristics as measured by plaque number and luminal stenosis were associated with WMH burden.

Efficacy of high-resolution vessel wall MRI in the postoperative assessment of intracranial aneurysms following flow diversion treatment.

Certain patients must undergo frequent postoperative digital subtraction angiography (DSA) after flow diversion (FD) therapy. No imaging modality with an efficacy comparable to that of DSA has been established. This study was conducted to determine the efficacy of contrast-enhanced delay alternating with nutation for tailored excitation (DANTE) T1-sampling perfection with application-optimized contrasts by using different flip angle evolution (SPACE), a high-resolution vessel wall magnetic resonance imaging technique for evaluating the occlusion status of intracranial aneurysms after FD treatment, with DSA serving as the reference standard. This retrospective study included 23 patients with 26 aneurysms who had undergone FD treatment between April 2016 and May 2022. Contrast-enhanced DANTE T1-SPACE and DSA were performed as postoperative follow-up imaging studies at 45 time points, both in the same period. The agreement rates for aneurysm occlusion status in the 45 imaging studies were examined. Contrast-enhanced DANTE T1-SPACE had a sensitivity and specificity of 96.3% (26/27) and 83.3% (15/18), respectively, for detecting aneurysm remnants. Overall, 91.1% (41/45) of findings detected on contrast-enhanced DANTE T1-SPACE were consistent with those on DSA. The findings detected on contrast-enhanced DANTE T1-SPACE were completely consistent with those of intraaneurysmal residual blood flow identified on DSA or high-resolution cone-beam computed tomography images in 74.1% (20/27) of the examinations that showed incomplete occlusion on DSA. Furthermore, parent artery status after FD treatment on contrast-enhanced DANTE T1-SPACE was consistent with that observed on DSA in 97.8% (44/45) of examinations. Contrast-enhanced DANTE T1-SPACE is a very useful option in the follow-up of aneurysms after FD treatment.

Contrast enhancement patterns associated with acute stroke in moyamoya disease using MR vessel wall imaging.

High-resolution magnetic resonance imaging (HR-MRI) can provide valuable insights into the histopathological characteristics of moyamoya disease (MMD). However, the patterns of vessel wall contrast enhancement have not been well established. We aimed to identify the contrast enhancement patterns of the vessel walls associated with acute cerebral infarction using HR-MRI in MMD. In this retrospective study, we conducted genetic tests for Ring Finger Protein 213 (RNF213) and performed HR-MRI on patients suspected of having MMD. We analyzed wall enhancement patterns including concentric, eccentric, or mixed enhancement types, and the occurrence of acute cerebral infarction in patients who simultaneously tested positive for RNF213 and exhibited definite features of MMD on HR-MRI. Among 306 patients who underwent RNF213 tests for the evaluation of MMD, 56 showed positive RNF213, and HR-MRI was performed on 32 of them. Among the patients with acute cerebral infarction, the incidence rate was significantly higher in the group with concentric wall enhancement compared to patients without acute cerebral infarction (73.3%vs. 17.0%, p<.002). Furthermore, the incidence was notably elevated, even in patients with pure concentric wall enhancement (40.0%vs. 5.9%, p=.033). The area under the curve (AUC) for the group with any concentric wall enhancement showed a significant result of.78 (95% confidence interval [CI]:.61-.95, p=.007), whereas the predictive ability for pure concentric wall enhancement did not reach significance (AUC=.67, 95% CI:.48-.86, p=.100). Concentric wall enhancement was a significant predictor of acute cerebral infarction in patients with MMD.

Temporal Changes on Postgadolinium MR Vessel Wall Imaging Captures Enhancement Kinetics of Intracranial Atherosclerotic Plaques and Aneurysms.

Analysis of vessel wall contrast kinetics (ie, wash-in/washout) is a promising method for the diagnosis and risk-stratification of intracranial atherosclerotic disease plaque (ICAD-P) and the intracranial aneurysm walls (IA-W). We used black-blood MR imaging or MR vessel wall imaging to evaluate the temporal relationship of gadolinium contrast uptake kinetics in ICAD-Ps and IA-Ws compared with normal anatomic reference structures. Patients with ICAD-Ps or IAs who underwent MR vessel wall imaging with precontrast, early postcontrast (5-15 minutes), and delayed postcontrast (20-30 minutes) 3D T1-weighted TSE sequences were retrospectively studied. ROIs of a standardized diameter (2 mm) were used to measure the signal intensities of the cavernous sinus, pituitary infundibulum, temporalis muscle, and choroid plexus. Point ROIs were used for ICAD-Ps and IA-Ws. All ROI signal intensities were normalized to white matter signal intensity obtained using ROIs of 10-mm diameter. Measurements were acquired on precontrast, early postcontrast, and delayed postcontrast 3D T1 TSE sequences for each patient.ajnr;45/9/1206/T1T1T1Table 1:MR-VWI parameters for ICAD-Ps and IAsParameterValueSequence3D TSEScan planeAxialFOV (mm)160TR/TE (ms)800/28-32BW (Hx/pixel)370θ120Acceleration2ETL42Matrix acquisition0.5 mm ×0.5 mmMatrix recon0.5 mm ×0.5 mmNo. of slices/thick120/0.5Note:-FOV indicates field of view; TR, the repetition time; TE, the echo time; BW, bandwidth; ETL, echo train length; Matrix recon, matrix reconstruction. Ten patients with 17 symptomatic ICAD-Ps and 30 patients with 34 IA-Ws were included and demonstrated persisting contrast uptake (P < .001) of 7.21% and 10.54% beyond the early phase (5-15 minutes postcontrast) and in the delayed phase (20-30 minutes postcontrast) on postcontrast MR vessel wall imaging. However, normal anatomic reference structures including the pituitary infundibulum and cavernous sinus demonstrated a paradoxical contrast washout in the delayed phase. In both ICAD-Ps and IA-Ws, the greatest percentage of quantitative enhancement (>70%-90%) occurred in the early phase of postcontrast imaging, consistent with the rapid contrast uptake kinetics of neurovascular pathology. Using standard MR vessel wall imaging techniques, our results demonstrate the effects of gadolinium contrast uptake kinetics in ICAD-Ps and IA-Ws with extended accumulating enhancement into the delayed phase (> 15 minutes) as opposed to normal anatomic reference structures that conversely exhibit decreasing enhancement. Because these relative differences are used to assess qualitative patterns of ICAD-P and IA-W enhancement, our findings highlight the importance of standardizing acquisition time points and MR vessel wall imaging protocols to interpret pathologic enhancement for the risk stratification of cerebrovascular pathologies.

High-resolution MR vessel wall imaging and cardiovascular health for evaluating the occurrence of ischemic stroke

ObjectivesTo explore the value of high-resolution MR vessel wall imaging (HR-VWI) based plaque characteristics combined with cardiovascular health (CVH) metrics in the risk evaluation of ischemic stroke attributed to middle cerebral artery (MCA) atherosclerotic stenosis. MethodsRetrospective analysis of 209 participants with middle cerebral atherosclerosis, 146 patients with high signal in the MCA area on DWI were included in the symptomatic group, and 63 patients were included in the asymptomatic group. The degree of stenosis, enhancement ratio, plaque burden, remodeling index, and intraplaque hemorrhage were measured and compared between groups. Seven CVH metrics and other clinical data were obtained. The association between these factors and ischemic stroke was investigated by univariate and multivariate analysis. ResultsThe degree of stenosis [OR, 1.036 (95 % CI, 1.014–1.058); P = 0.001], plaque burden [OR, 0.958 (95 % CI, 0.928–0.989); P = 0.009], intraplaque hemorrhage [OR, 3.530 (95 % CI, 1.233–10.110); P = 0.019], physical activity [OR, 4.321 (95 % CI, 1.526–12.231); P = 0.006], and diet [OR, 8.986 (95 % CI, 2.747–29.401); P < 0.001] were the independent characteristics associated with the occurrence of ischemic stroke. ROC curve showed that the combination of plaque characteristics, diet, and physical activity achieved the highest AUC of 0.828 (95 % CI 0.770–0.877; P < 0.001), with sensitivity and specificity being 86.30 % and 66.67 %, respectively. ConclusionPlaque characteristics combined with CVH metrics may identify high-risk populations for ischemic stroke and offer novel insights into risk evaluation and stratification.

Application of high-resolution MRI in evaluating statin efficacy on symptomatic intracranial atherosclerosis.

To investigate the efficacy of statins on symptomatic intracranial atherosclerotic plaques using high-resolution 3.0 T MR vessel wall imaging (HR-MRI). Patients with symptomatic intracranial atherosclerotic plaques (cerebral ischemic events within the last three months) confirmed by HR-MRI from July 2017 to August 2022 were retrospectively included in this study. The enrolled patients started statin therapy at baseline. All the patients underwent the follow-up HR-MRI examination after statin therapy for at least 3 months. A paired sample t-test and Wilcoxon rank sum test were used to evaluate the changes in plaque characteristics after statin therapy. Multivariate linear regression was further used to investigate the clinical factors associated with statin efficacy. A total of 48 patients (37 males; overall mean age = 60.2 ± 11.7 years) were included in this study. The follow-up time was 7.0 (5.6-12.0) months. In patients treated with statins for > 6 months (n = 31), plaque length, wall thickness, plaque burden, luminal stenosis and plaque enhancement were significantly reduced. Similar results were found in patients with good lipid control (n = 21). Younger age, lower BMI and hypertension were associated with decreased plaque burden. Lower BMI, hypertension and longer duration of statin therapy were associated with decreased plaque enhancement. Younger age and hypertension were associated with decreased luminal stenosis (all p < 0.05). HR-MRI can effectively evaluate plaques changes after statin therapy. Statins can reduce plaque burden and stabilize plaques. The effect of statin may have a relationship with age, BMI, hypertension, and duration of statin therapy. High-resolution MRI can be applied to evaluate the efficacy of statins on symptomatic intracranial atherosclerotic plaques. Long-term statin use and well-controlled blood lipid levels can help reduce plaque burden and stabilize plaques. High-resolution MRI provides great help evaluating the changes of plaque characteristics after statin therapy. Efficacy of statins is associated with duration of use, controlled lipid levels, and clinical factors. High-resolution MRI can serve as an effective method for following-up symptomatic intracranial atherosclerosis.

Risk Factors and Clinical Significance of Ultra-Long-Term Microischemia After Intracranial Aneurysm Embolization.

This study aimed to explore influencing factors and clinical significance of ultra-long-term microischemia following intracranial aneurysm (IA) embolization and establish a theoretical foundation for reducing both the incidence of ultra-long-term microischemia and cognitive dysfunction in patients post embolization. A retrospective analysis was conducted on data from 147 patients who received endovascular treatment for IAs. Patients were categorized into microischemic and control (non-microischemic) groups on the based on the findings of high-resolution magnetic resonance vessel wall imaging (HR-VWI) examinations performed 3days postoperatively and 6months postoperatively. Risk factors for the occurrence of ultra-long-term microischemia were determined by univariate analysis and multivariate logistic regression analysis. Out of 147 patients included in the study, 51 (34.69%) developed microischemia while the remaining 96 (65.31%) did not experience this condition. Analysis revealed that factors such as sex, age, history of underlying diseases (hypertension, diabetes mellitus), aneurysmal site characteristics, the presence or absence of stenosis in the aneurysm-bearing artery, modified Fisher score at admission, Barthel's index at discharge, immunoinflammatory index at 3days postoperatively and at the 6-month follow-up, the presence or absence of aneurysmal wall enhancement, and the presence or absence of aneurysmal lumen showed no statistically significant differences between the two groups (all P > 0.05). By contrast, variables like in operative time, rupture status of the aneurysm before surgery according to World Federation of Neurologic Surgeons (WFNS) grade, aneurysm size, number of stents used, number of guidewires and catheters used, and Evans index between the two groups were found to have statistically significant disparities between those who developed microischemia and those who did not (P < 0.05). A subsequent multivariate analysis revealed that aneurysm size, Evans index, and the number of stents used were independent risk factors for the occurrence of ultra-long-term microischemia after surgical intervention of aneurysms (P < 0.05). The receiver operating characteristic (ROC) curves of the patients were constructed on the basis of risk factors determined through multivariate logistic regression analysis. Results indicated that aneurysm size (area under ROC curve (AUC) 0.619, sensitivity 94.7%, specificity 17.1%, P = 0.049), Evans index (AUC 0.670, sensitivity 96.4%, specificity 26.8%, P = 0.004), and number of stents (AUC 0.639, sensitivity 44.6%, specificity 90.2%, P < 0.001) effectively predicted the occurrence of microischemia. The incidence of cognitive dysfunction was higher in the microischemic group than in the control group (P < 0.05), and a greater number of microischemic foci was associated with a higher incidence of cognitive dysfunction. The proportion of microschemia foci in the thalamus and basal ganglia in patients with cognitive dysfunction (60.87%) was significantly higher than that in patients without cognitive dysfunction (34.55%) (P < 0.05). Aneurysm size, Evans index > 0.3, and the quantity of stents were independent risk factors for the occurrence of ultra-long-term microischemia after aneurysm embolization and provided good predictive performance. Cognitive dysfunction was closely associated with microischemia, with its severity increasing with an increase in the number of ischemic foci.

Short-term glycemic variability and intracranial atherosclerotic plaque stability assessed by high-resolution MR vessel wall imaging in type 2 diabetes mellitus

ObjectiveTo investigate the relationship between short-term glycemic variability in patients with T2DM and the vulnerability of intracranial atherosclerotic plaques using HR-MR-VWI. Materials and methodsIn total, 203 patients with acute ischemic stroke (AIS)/transient ischemia (TIA) combined with T2DM were enrolled. All of them underwent HR-MR-VWI during the period between July 2020 and July 2023. 203 patients were divided into groups with higher (1,5-AG≤ 30.7 μmol/L) and lower (1,5-AG> 30.7 μmol/L) short-term glycemic variability. Patients were also divided into the T1WI and non-T1WI hyperintensity groups. Associated factors(FBG, HbA1c, and 1,5-AG)for the T1WI hyperintensity were analyzed by binary logistic regression. We used the area under the curve (AUC), while the sensitivity and specificity were calculated at the optimal threshold. The Delong test was employed to compare the quality of the AUC of the predictors. ResultsThe group with higher short-term glycemic variability had a higher incidence of the hyperintensity on T1WI, higher degree of enhancement, higher degree of stenosis and smaller lumen area (P < 0.05). The T1WI hyperintensity group had higher HbA1c levels, higher hemoglobin levels and lower 1,5-AG levels(P < 0.05). 1,5-AG (OR = 0.971, 95 % CI: 0.954∼0.988, P = 0.001), HbA1c (OR=1.305, 95 % CI: 1.065∼1.598, P = 0.01) and male sex (OR = 2.048, 95 % CI: 1.016∼4.128, P = 0.045)/(OR=2.102, 95 % CI: 1.058∼4.177, P = 0.034) were independent risk factors for the hyperintensity on T1WI. 1,5-AG demonstrated enhanced performance and yielded the highest AUC of the receiver operator characteristic curve (AUC = 0.726), with sensitivity and specificity values of 0.727 and 0.635 respectively. Conclusion1,5-AG, HbA1c and male sex are independent predictors of intracranial plaques with T1WI hyperintensity, the greater short-term glycemic variability, the higher incidence of vulnerable plaques.

Relationship between the intravascular enhancement sign on three-dimensional T1-weighted turbo spin echo and intraluminal thrombus in middle cerebral artery atherosclerosis

PurposeTo investigate the association between the intravascular enhancement sign (IVES) and intraluminal thrombus (ILT) detected by high-resolution magnetic resonance vessel wall imaging (HR-VWI) in patients with middle cerebral artery (MCA) atherosclerosis. MethodThe data of patients who underwent HR-VWI between May 2021 and May 2023, including clinical information, the number of IVES vessels, stenosis degree, ILT, plaque features on 3D T1-weighted turbo spin echo sequences, and signal intensity ratio (SIR) on 3D time-of-flight magnetic resonance angiography, were retrospectively analyzed. Correlation and logistic regression analyses were performed. ResultsA total of 194 MCA plaques were identified in 132 patients (103 [53 %] on the left). Atherosclerosis with, relative to without, ILT was associated with a higher incidence of ischemic events, higher plaque enhancement and stenosis degrees, more vessels with IVES, and lower remodeling ratio, lumen area, wall area, total vessel area, and SIR. Multivariate logistic regression analysis showed significant and independent associations of the number of IVES vessels (OR = 1.089; 95 % CI [1.013–1.170]; P = 0.020) and SIR (OR = 0.007; 95 % CI [0.0004–0.124]; P < 0.001) with ILT. The number of vessels with the IVES (AUC = 0.81, 95 % CI [0.75–0.87]; P < 0.001) and SIR (AUC = 0.88, 95 % CI [0.82–0.94]; P < 0.001) sufficiently diagnosed ILT, and the AUC of the combination of the IVES and SIR was 0.89 (95 % CI [0.84–0.94]; P < 0.001). ConclusionThe number of IVES vessels and SIR are independent risk factors for ILT. They may provide new monitoring targets for stroke prevention in patients with atherosclerotic stenosis.

Neuro-Behcet’s Disease Manifesting as Bilateral Fornix and Left Thalamus Infarction

Neuro-Behcet’s disease (NBD) is defined as neurological involvement in Behcet’s disease. A 32-year-old man was admitted due to sudden memory impairment and had a history of recurrent oral/genital ulcers. Brain magnetic resonance imaging (MRI) revealed ischemic lesions in the bilateral fornix and left thalamus, and high-resolution vessel wall MRI demonstrated vasculitis in the anterior communicating artery. We report a rare case of NBD that presented as vasculitis and ischemic stroke in the bilateral fornix and thalamus.

The Contribution of Vessel Wall Magnetic Resonance Imaging to the Diagnosis of Primary and Secondary Central Nervous System Vasculitis.

To describe high-resolution brain vessel wall MRI (VW-MRI) patterns and morphological brain findings in central nervous system (CNS) vasculitis patients. Fourteen patients with confirmed CNS Vasculitis from two tertiary centers underwent VW-MRI using a 3T scanner. The images were reviewed by two neuroradiologists to assess vessel wall enhancement characteristics and locations. Fourteen patients were included (six females; average age 48 ± 19 years). Diagnoses included primary CNS vasculitis (PCNSV) in six patients and secondary CNS vasculitis (SCNSV) in eight, half of which were infection-related. Thirteen patients showed vessel wall enhancement, which was intense in eleven patients (84.6%) and concentric in twelve (92.3%), affecting the anterior circulation in nine patients (69.2%), posterior in two patients (15.4%), and both circulations in two patients (15.4%). The enhancement patterns were similar across different CNS vasculitis types. DWI changes corresponded with areas of vessel wall enhancement in 77% of patients. Conclusions: CNS vasculitis is often associated with intense, concentric vessel wall enhancement in VW-MRI, especially in the anterior circulation. The consistent presence of DWI alterations in affected territories suggests a possible link to microembolization or hypoperfusion. These imaging findings complement parenchymal brain MRI and MRA/DSA data, potentially increasing the possibility of a clinical diagnosis of CNS vasculitis.