FLAIR Vascular Hyperintensity Research Articles

Abstract TMP9: Flair Vascular Hyperintensities as Imaging Biomarker in Pediatric Arterial Ischemic Stroke

Background: FLAIR vascular hyperintensities (FVH) are high signal intensities on MRI resulting from sluggish flow through collateral vessels in patients with acute arterial ischemic stroke (AIS). Data from adults suggest they may be a marker of penumbra. In this first investigation of FVH in children, I measured the prevalence and identified risk factors for FVH in pediatric patients with AIS. Methods: Retrospective review of patients prospectively enrolled in the CHOP Stroke Registry from 2006-2022. Patients with AIS age 29 days to 18 years with MRI within 72 hours of last known well were included. Children with pre-existing strokes, vasculopathy, prior brain surgery, radiation, or vascular compression from intracranial mass were excluded. MRIs were assessed by a blinded reviewer and adjudicated by a neuroradiologist for presence of LVO, FVH score, modASPECTS score, and AIS lesion volume. Clinical data were abstracted from chart review. Independent sample t-test compared FVH score and LVO presence. Pearson's correlation assessed the relationship between total FVH score and age, stroke size, modASPECTS, and pedNIHSS scores. Multivariable logistic regression evaluated predictors of significant FVH (score >= 3) and included time to MRI, large vessel occlusion, modASPECTS, pedNIHSS, stroke size, and age as independent variables. Results: 83 patients met inclusion criteria. Median time to MRI was 26 hours (95% CI 26-33). FVH were present in 45 patients (54%). Mean FVH score was higher in patients with LVO (5.22 ± 0.64) compared to those without (1.21 ± 0.24; p = 0.00). There was a positive correlation between total FVH score and age (p < 0.05), stroke size (p < 0.0001), modASPECTS (p < 0.0000), and pedNIHSS (p < 0.0002). In the multivariate logistic regression, only older age (OR 1.50, 95% CI 1.12-2.01, p < 0.006) and presence of LVO (OR 0.002, 95% CI 4.85x10 -5 -0.08, p<0.001) were associated with significantly increased odds of high FVH burden. Conclusions: FVH are prevalent in children with AIS, with higher burden in older children. Similar to adults, large vessel occlusion and larger infarct size are associated with higher FVH burden. Further study is needed on whether FVH could be used to identify patients who would benefit from reperfusion therapies.

Abstract WP132: The Significance of Fluid-Attenuated Inversion Recovery Vascular Hyperintensity in Combination With Occlusion Site and Reperfusion Status by Mechanical Thrombectomy for Proximal and Distal Middle Cerebral Artery Occlusion

Introduction: In patients with acute ischemic stroke, FLAIR vascular hyperintensity (FVH) is a reliable indicator of large vessel occlusion and salvageable tissue requiring mechanical thrombectomy (MT). However, its significance in distal arterial occlusion has not been established. This study aimed to investigate the significance of FVH in DWI-negative areas, in combination with occlusion site and reperfusion status, by MT for regional tissue outcomes in proximal and distal middle cerebral artery (MCA) occlusion. Methods: The clinical records of patients admitted to a single institute between April 2017 and June 2022, who presented with MCA occlusion with initial NIHSS ≥ 5 and underwent MT within 24 h of onset were retrospectively analyzed. Proximal occlusion was defined as M1 segment occlusion, and distal occlusion as M2 or M3 segment based on initial MRA. Each cortical MCA area in Alberta Stroke Program Early CT Score (ASPECTS) ipsilateral to the occluded vessel was categorized into group A (DWI-, FVH-) or B (DWI-, FVH+) based on initial MRI. Regional collateral status on initial angiogram, expanded Thrombolysis in Cerebral Infarction (eTICI) grade on final angiogram, and regional unfavorable tissue outcome with the appearance of low or high density on CT 24 h after MT were recorded. Univariate and multivariate analyses using mixed-effects models for regional unfavorable tissue outcome were performed. Results: A total of 103 patients (56 with proximal and 47 with distal occlusion) were included. Categorizing cortical areas resulted in 256 areas in group A and 171 in group B. The rate of unfavorable tissue outcome in order of eTICI 0-2a, 2b50-67, and 2c-3 reperfusion status in group A were 14.3%, 11.3%, and 6.0%, respectively (p=0.06) while those in group B were 47.1%, 34.0%, and 12.9%, respectively (p<0.01). In multivariate analysis, eTICI 0-2b67 vs. eTICI 2c-3 in group B of distal occlusion was an independent predictor for unfavorable regional tissue outcome (OR 7.8, 95% CI 1.1-55.6, p=0.04), along with ASPECTS M2 or M5 and poor angiographical collaterals. Conclusions: FVH in DWI-negative areas can reveal penumbra tissue secondary to both proximal and distal MCA occlusions. However, salvage requires fairly reliable reperfusion in distal occlusion.

FLAIR vascular hyperintensity combined with asymmetrical prominent veins in acute anterior circulation ischemic stroke: prediction of collateral circulation and clinical outcome

BackgroundTo investigate the value of fluid-attenuated inversion recovery vascular hyperintensity (FVH) within asymmetrical prominent veins sign (APVS) on susceptibility-weighted imaging predicting collateral circulation and prognosis in patients with acute anterior circulation ischemic stroke.MethodPatients with severe stenosis or occlusion of ICA or MCA M1, who underwent MRI within 72 h from stroke onset were reviewed. The Alberta Stroke Program Early CT Score was used to evaluate the volume of infarction on DWI, the degree of FVH and APVS. Spearman correlation analysis was used to evaluate the correlation between FVH and APVS. All patients were divided into the good prognosis group and the poor prognosis group according to the score of the modified ranking scale (mRS) 90 days after the stroke. Logistic regression analysis was used to explore the relationship between FVH and APVS and functional prognosis, while receiver operating characteristic (ROC) curves were plotted to assess the value of FVH and APVS in predicting prognosis.ResultsSpearman correlation analysis revealed moderate positive correlations between FVH and APVS (r = 0.586, P < 0.001). The poor prognosis group had a higher rate of a history of atrial fibrillation, a larger cerebral infarction volume, a higher NIHSS score at admission, and a higher FVH and APVS score compared with the good prognosis group (all P < 0.05). A further logistic regression indicated that the NIHSS score, cerebral infarction volume, FVH and APVS were independent risk factors for a poor functional prognosis. In terms of FVH, APVS, alone and their combination for the diagnosis of poor prognosis, the sensitivity, specificity, area under the ROC curve (AUC), and 95% confidence interval (CI) were 86.8%, 83.3%, 0.899 (95% CI 0.830–0.968); 60.5%, 93.7%, 0.818 (95% CI 0.723–0.912); 86.8%, 89.6%, 0.921 (95% CI 0.860–0.981), respectively.ConclusionThe presence of FVH and APVS can provide a comprehensive assessment of collateral circulation from the perspective of veins and arteries, and the correlation between the two is positively correlated. Both of them were independent risk factors for poor prognosis, their combination is complementary and can improve the predictive value.

Value of MRI T2 FLAIR Vascular Hyperintensities Combined with DWI ASPECTS in Predicting the Prognosis of Acute Cerebral Infarction with Endovascular Treatment.

To explore the MRI T2 fluid-attenuated inversion recovery (FLAIR) vascular hyperintensities (FVH) combined with diffusion-weighted imaging (DWI) Alberta Stroke Program Early CT Score (ASPECTS) in predicting the prognosis of acute cerebral infarction (ACI) with endovascular treatment. The patients with ACI in the anterior circulation who underwent endovascular treatment from June 2016 to December 2020 were divided into a good prognosis group and a poor prognosis group according to the modified Rankin Scale (mRS) score at 90 days after the operation. The differences in general clinical baseline data, CT-ASPECTS, FVH, and DWI-ASPECTS between the two groups were analyzed. The receiver operating characteristic (ROC) curve was used to analyze the predictive power of prediction models on prognosis. The results of the Binomial Logistic regression equation showed initial National Institute of Health stroke scale (NIHSS), Mori grade, DWI-ASPECTS, and FVH were independent risk factors for prognosis. The predictive power of the FVH + DWI-ASPECTS prediction model was highest, and the predictive power of DWI-ASPECTS was higher than that of CT-ASPECTS. DWI-ASPECTS is better than CT-ASPECTS in predicting the prognosis of ACI with endovascular treatment, and the combined prediction model of FVH and DWI-ASPECTS has higher prediction performance, which can be used as a preoperative evaluation method to predict the effect of endovascular treatment for ACI.

FLAIR vascular hyperintensity-DWI mismatch and DWI-FLAIR mismatch ASPECTS for prediction of good outcome after recanalization in anterior circulation stroke; multicenter observational study

IntroductionAcute ischemic stroke is a medical emergency caused by decreased blood flow to the brain, leading cause of long-term disability. Recanalization, one of the most concerning difficulties linked with intracranial arterial occlusion, has been used to reduce mortality in ischemic stroke treatment. The mismatch concepts MR PWI-DWI or DWI-FLAIR can help identify patients for thrombolysis. PurposeThis paper introduces a novel method of predicting revascularization using the value of fluid-attenuated inversion recovery vascular hyperintensity FVH-DWI mismatch and DWI-FLAIR mismatch, which releases anterior circulation large vessel occlusion (LVO) after endovascular thrombectomy (EVT). Moreover, we present a new scoring system following anatomical region distributed for MCA territory called a DWI-FLAIR MISMATCH ASPECTS. ResultStatistical analysis was performed to predict revascularization and functional outcome with 110 patients with anterior circulation LVO treated with EVT. We found that FVH-DWI mismatch was present in 71 patients (89.9 %) with complete revascularization and present in 8 patients (10.1 %) with no/partial revascularization, which had no significant difference (p = 0.12), and there was no significant difference between good functional outcome and poor functional outcome. Moreover, in 76 patients with DWI-FLAIR mismatch ASPECTS of > 6 point-group, present FVH-DWI mismatch in 57 patients (83.8 %) with complete revascularization had a significant difference as compared to 11 patients (16.2 %) with absent FVH-DWI mismatch (p < 0.05). The clinical outcome in complete revascularization is better than no/partial revascularization, and complete revascularization is independently associated with good functional outcomes (p < 0.05). ConclusionFVH-DWI mismatch paired with DWI-FLAIR mismatch ASPECTS > 6 points may be possible to predict revascularization in patients with anterior circulation LVO.

Ultrafast MRI using deep learning echoplanar imaging for a comprehensive assessment of acute ischemic stroke.

Acute ischemic stroke (AIS) is an emergency requiring both fast and informative MR sequences. We aimed to assess the performance of an artificial intelligence-enhanced ultrafast (UF) protocol, compared to the reference protocol, in the AIS management. We included patients admitted in the emergency department for suspected AIS. Each patient underwent a 3-T MR protocol, including reference acquisitions of T2-FLAIR, DWI, and SWI (duration: 7min 54s) and their accelerated multishot EPI counterparts for T2-FLAIR and T2*, complemented by a single-shot EPI DWI (duration: 1min 54s). Two blinded neuroradiologists reviewed each dataset, assessing DWI (detection, location, number of acute lesions), FLAIR (vascular hyperintensities, visibility of acute lesions), and SWI/T2* (hemorrhagic transformation, thrombus). We compared the agreement between the diagnoses obtained with both protocols using kappa coefficients. A total of 173 patients were included consecutively, of whom 80 with an AIS in DWI. We found an almost perfect agreement between the UF and reference protocols regarding the detection, distribution, number of AIS in DWI (κ = 0.98, 0.98, and 0.87 respectively), the presence of vascular hyperintensities, and the presence of a parenchymal hyperintensity in the AIS region in FLAIR (κ = 0.93 and 0.89 respectively). Agreement was substantial in T2*/SWI for thrombus detection, and fair for hemorrhagic transformation detection (κ = 0.64 and 0.38 respectively). Differential diagnoses were similarly detected by both protocols (κ = 1). Our AI-enhanced ultrafast MRI protocol allowed an effective detection and characterization of both AIS and differential diagnoses in less than 2min. • The AI-enhanced ultrafast MRI protocol allowed an effective detection of acute stroke. • Characterization of stroke features with the UF protocol was equivalent to the reference sequences. • Differential diagnoses were detected similarly by the UF and reference protocols.

FLAIR Vascular Hyperintensities as a Surrogate of Collaterals in Acute Stroke: DWI Matters.

FLAIR vascular hyperintensities are thought to represent leptomeningeal collaterals in acute ischemic stroke. However, whether all-FLAIR vascular hyperintensities or FLAIR vascular hyperintensities-DWI mismatch, ie, FLAIR vascular hyperintensities beyond the DWI lesion, best reflects collaterals remains debated. We aimed to compare the value of FLAIR vascular hyperintensities-DWI mismatch versus all-FLAIR vascular hyperintensities for collateral assessment using PWI-derived collateral flow maps as a reference. We retrospectively reviewed the registries of 6 large stroke centers and included all patients with acute stroke with anterior circulation large-vessel occlusion who underwent MR imaging with PWI before thrombectomy. Collateral status was graded from 1 to 4 on PWI-derived collateral flow maps and dichotomized into good (grades 3-4) and poor (grades 1-2). The extent of all-FLAIR vascular hyperintensities and FLAIR vascular hyperintensities-DWI mismatch was assessed on the 7 cortical ASPECTS regions, ranging from 0 (absence) to 7 (extensive), and associations with good collaterals were compared using receiver operating characteristic curves. Of the 209 included patients, 133 (64%) and 76 (36%) had good and poor collaterals, respectively. All-FLAIR vascular hyperintensity extent was similar between collateral groups (P = .76). Conversely, FLAIR vascular hyperintensities-DWI mismatch extent was significantly higher in patients with good compared with poor collaterals (P < .001). The area under the curve was 0.80 (95% CI, 0.74-0.87) for FLAIR vascular hyperintensities-DWI mismatch and 0.52 (95% CI, 0.44-0.60) for all-FLAIR vascular hyperintensities (P < .001 for the comparison), to predict good collaterals. Variables independently associated with good collaterals were smaller DWI lesion volume (P < .001) and larger FLAIR vascular hyperintensities-DWI mismatch (P = .02). In acute ischemic stroke with large-vessel occlusion, the extent of FLAIR vascular hyperintensities does not reliably reflect collateral status unless one accounts for DWI.

Association of fluid-attenuated inversion recovery vascular hyperintensity with ischaemic events in internal carotid artery or middle cerebral artery occlusion

Background and purposeIndividuals with intracranial artery occlusion have high rates of ischaemic events and recurrence. It has been challenging to identify patients who had high-risk stroke using a simple, valid...

Fluid-attenuated inversion recovery vascular hyperintensity-diffusion-weighted imaging mismatch and functional outcome after endovascular reperfusion therapy for acute ischemic stroke.

Fluid-attenuated inversion recovery vascular hyperintensity (FVH) outside of the diffusion-weighted imaging (DWI) lesion, termed FVH-DWI mismatch, may represent penumbral tissue with good collateral status. Consecutive patients who underwent endovascular reperfusion therapy (EVT) for acute internal carotid artery (ICA) or middle cerebral artery (MCA)-M1 occlusion were enrolled. FVH-DWI mismatch score was defined as the number of cortical Alberta Stroke Program Early CT Score areas (I and M1 to M6) that involved FVH but no DWI lesion (0 to 7 points). The outcome measure was set as good functional outcome, defined as a modified Rankin Scale score of 0 to 2, at 90 days after onset. Of 196 consecutive patients who underwent EVT for acute ICA or MCA-M1 occlusion, 32 without brain MRI before EVT were excluded, and the remaining 164 were analyzed. The median FVH-DWI mismatch score was 2 (interquartile range, 0 to 4). At 90 days after EVT, 2 patients were lost-to follow-up, and 73 had good functional outcome. The frequency of good functional outcome at 90 days after EVT increased significantly with increasing FVH-DWI mismatch score (P for trend <0.001). FVH-DWI mismatch score was independently associated with good functional outcome at 90 days after onset (adjusted odds ratio per 1 point,1.46; 95% confidence interval, 1.15-1.89). Patients with large FVH-DWI mismatch had good functional outcome after EVT for acute ICA or MCA-M1 occlusion.

FLAIR Vascular Hyperintensity: An Important MRI Marker in Patients with Transient Ischemic Attack.

PurposeWe aimed to investigate the prevalence of fluid-attenuated inversion recovery (FLAIR) vascular hyperintensities (FVHs) and the clinical–radiological correlation in transient ischemic attack (TIA) patients.Materials and MethodsWe performed a retrospective analysis of TIA patients who had undergone magnetic resonance imaging (MRI) within 24 h of symptom onset. Two independent neuroradiologists investigated the presence of FVHs, large-artery severe stenosis or occlusion (LASO) in magnetic resonance angiograms, and the nature of factors associated with FVH.ResultsA total of 207 patients were enrolled in this study. FVHs were detected in 42 (20.3%) patients, in whom atrial fibrillation (AF) was confirmed in 25 (59.5%) cases and LASO was confirmed in 30 (71.4%) cases. The corresponding figures were 33 (20.0%) and 10 (6.1%), respectively, for the 165 FVH-negative patients. Logistic regression analysis showed that time from symptom onset to MRI (odds ratio [OR] = 0.82, 95% CI 0.76–0.97, p = 0.042), previous stroke (OR = 2.95, 95% CI 1.58–6.74, p = 0.002), AF (OR = 5.83, 95% CI 2.24–9.46, p < 0.001), and LASO (OR = 4.28, 95% CI 2.96–10.28, p < 0.001) were independently associated with FVH. Overall, the sensitivity and specificity of FVH for predicting LASO were 0.75 and 0.93, respectively, and the positive predictive value, negative predictive value, and accuracy were 0.71, 0.94, and 0.89, respectively. The area under the receiver operating characteristic curve was 0.839. FVH-positive TIA patients with LASO had less AF (14 [46.7%] versus 11 [91.7%], p = 0.019) and longer times from symptom onset to MRI (6.8 ± 2.8 h versus 4.8 ± 1.3 h, p = 0.004) than those without LASO.ConclusionThe presence of FVH could be an important marker in TIA patients. Many factors, including LASO, AF, and time from symptom onset to MRI, are associated with the detection of FVH.

Prognostic value of post-treatment fluid-attenuated inversion recovery vascular hyperintensity in ischemic stroke after endovascular thrombectomy.

To explore the value of post-treatment fluid-attenuated inversion recovery vascular hyperintensity (FVH) in predicting clinical outcome in patients with acute ischemic stroke (AIS) after endovascular thrombectomy (EVT). This retrospective study reviewed data from consecutive patients with large vessel occlusion of anterior circulation between July 2017 and February 2021. Together with other variables, status of post-treatment FVH was assessed for each patient. Good outcome was defined as a 3-month modified Rankin Scale score of 0-2. Chi-square test, Fisher's exact test, independent-samples t test, multivariate logistic regression analysis, and receiver operating characteristic analysis were used as appropriate. Among 84 included patients, 48 (57.1%) patients showed post-treatment FVH. Post-treatment FVH significantly correlated with incomplete recanalization (p < 0.05) and low Alberta Stroke Project Early CT Changes Score on post-treatment diffusion-weighted imaging (p < 0.05). Higher incidence of hemorrhage transformation was observed in patients with post-treatment FVH than those without (27.1% vs. 16.7%); however, the difference did not reach significance (p = 0.259). Successful recanalization (odds ratio [OR], 0.024; 95% confidence interval [CI] 0.003-0.194; p < 0.05), lower National Institutes of Health Stroke Scale scores at admission (NIHSSpre) (OR, 1.196; 95% CI, 1.017-1.406; p < 0.05), and no post-treatment FVH (OR, 74.690; 95% CI, 4.624-1206.421; p < 0.05) were found to be independent predictors of good outcomes. Combined models integrating all three independent predictors (recanalization+NIHSSpre+post-treatment FVH) significantly outperformed the combined model without post-treatment FVH (recanalization+NIHSSpre) in predicting clinical outcome (p = 0.004). Post-treatment FVH may be an effective prognostic marker associated with clinical outcome in patients with AIS after EVT. • Post-treatment FVH correlates with incomplete recanalization and higher infarct volume. • Post-treatment FVH is independently associated with an unfavorable outcome. • Post-treatment FVH may provide prognostic information in patients with AIS after EVT.

FLAIR vascular hyperintensities predict functional outcome after endovascular thrombectomy in patients with large ischemic cores.

To establish whether collateral circulation was associated with functional outcome in stroke patients with large infarct size (Alberta Stroke Program Early CT Score [ASPECTS] ≤ 5) undergoing endovascular thrombectomy (EVT) METHODS: Consecutive patients with acute ischemic stroke due to large-vessel occlusion in the anterior circulation and an ASPECTS of ≤ 5 were analyzed. Quantification of collateral circulation was performed using a fluid-attenuated inversion recovery vascular hyperintensity (FVH)-ASPECTS rating system (score ranging from 0 [no FVH] to 7 [FVHs abutting all ASPECTS cortical areas]) by two independent neuroradiologists. Good functional outcome was defined by modified Rankin Scale (mRS) score of 0 to 3 at 3 months. We determined the association between FVH score and clinical outcome using multivariable regression analyses. A total of 139 patients (age, 63.1 ± 20.8 years; men, 51.8%) admitted between March 2012 and December 2017 were included. Good functional outcome (mRS 0-3) was observed in 65 (46.8%) patients, functional independence (mRS 0-2) was achieved in 43 (30.9%) patients, and 33 (23.7%) patients died at 90 days. The median FVH score was 4 (IQR, 3-5). FVH score was independently correlated with good outcome (adjusted OR = 1.41 [95% CI, 1.03-1.92]; p = 0.03 per 1-point increase). In stroke patients with large-volume infarcts, good collaterals as measured by the FVH-ASPECTS rating system are associated with improved outcomes and may help select patients for reperfusion therapy. • Endovascular thrombectomy can allow almost 1 in 2 patients with large infarct cores to achieve good functional outcome (modified Rankin Scale [mRS] of 0-3) and 1 in 3 patients to regain functional independence (mRS 0-2) at 3 months. • The extent of FVH score (as reflected by FLAIR vascular hyperintensity [FVH]-Alberta Stroke Program Early CT Score [ASPECTS] values) is associated with functional outcome at 3 months in this patient group.

Fluid-Attenuated Inversion Recovery Vascular Hyperintensity as a Potential Predictor for the Prognosis of Acute Stroke Patients After Intravenous Thrombolysis.

BackgroundFluid-attenuated inversion recovery vascular hyperintensity (FVH) can reflect the collateral status, which may be a valuable indicator to predict the functional outcome of acute stroke (AS) patients.MethodsA total of 190 AS patients with large vessel occlusion (LVO) were retrospectively investigated. All patients completed a 6-month follow-up and their modified Rankin Scale (mRS) scores were recorded at 1, 3, and 6 months after intravenous thrombolysis (IVT). Based on their mRS at 3 months, patients were divided into two groups: poor prognosis (131 patients; 68.9% of all subjects) and favorable prognosis (59 patients; 31.1% of all subjects). The death records of 28 patients were also analyzed in the poor prognosis group.Results(1) Univariate and multivariate analyses showed that the higher National Institutes of Health Stroke Scale (NIHSS) score at admission, higher fasting blood glucose, and lower FVH score were independent risk factors to predict the poor prognosis of IVT. (2) Survival analysis indicated that FVH score was the only baseline factor to predict the 6-month survival after IVT. (3) Baseline FVH score had great prediction performance for the prognosis of IVT (area under the curve = 0.853). (4) Baseline FVH score were negatively correlated with the NIHSS score at discharge and mRS score at 1, 3, and 6 months.ConclusionAmong various baseline clinical factors, only the FVH score might have implications for 3-month outcome and 6-month survival of AS patients after IVT. Baseline FVH score showed great potential to predict the prognosis of the AS patients.

FLAIR vascular hyperintensity predicts early neurological deterioration in patients with acute ischemic stroke receiving endovascular thrombectomy.

Fluid-attenuated inversion recovery vascular hyperintensity (FVH) is frequently observed in patients with acute ischemic stroke (AIS). FVH is associated with functional outcome at 3months in AIS patients receiving endovascular thrombectomy. In the present study, we assessed whether FVH predicted early neurological deterioration (END) and hemorrhagic transformation (HT) within 72h in AIS patients receiving endovascular thrombectomy. We retrospectively analyzed 104 patients with acute internal-carotid-artery or proximal middle-cerebral-artery occlusion within 16h after symptom onset. Before thrombectomy, all patients underwent brain magnetic resonance imaging. END was defined as an increase of 4 points or more from baseline National Institutes of Health Stroke Scale (NIHSS) during 72h following onset. HT was assessed by brain computedtomography. Statistical analyses were performed to predict END and HT. The proportion of high FVH score, high American Society of Intervention and Therapeutic Neuroradiology/Society of Interventional Radiology (ASITN/SIR) grade in non-END group was higher than that in END group (p < 0.001, p < 0.001, respectively). FVH score was positively correlated with ASITN/SIR grade (r = 0.461, p < 0.001). FVH score was a predictor factor for END (adjusted OR, 13.552; 95% CI, 2.408-76.260; p = 0.003), while FVH score was not a predictor factor for HT. Furthermore, NIHSS at admission (adjusted OR, 1.112; 95% CI, 1.006-1.228; p = 0.038) and high-density lipoprotein cholesterol (adjusted OR, 18.865; 95% CI, 2.998-118.683; p = 0.002) were predictor factors for HT. To assess FVH score before thrombectomy might be useful for predicting END in AIS patients receiving endovascular thrombectomy.

Hemodynamics derived from computational fluid dynamics based on magnetic resonance angiography is associated with functional outcomes in atherosclerotic middle cerebral artery stenosis.

To investigate the relationship between fluid-attenuated inversion recovery (FLAIR) vascular hyperintensity (FVH), hemodynamics, and functional outcome in atherosclerotic middle cerebral artery (MCA) stenosis using a computational fluid dynamics (CFD) model based on magnetic resonance angiography (MRA), according to a modified Rankin Scale (mRS) at 3 months. A total of 120 patients with 50-99% atherosclerotic MCA stenosis were included. The training and internal validation groups were composed of 99 participants and 21 participants, respectively. Demographic, imaging data, and functional outcome (mRS at 3 months) were collected. Hemodynamic parameters were obtained from the CFD model. The FVH score was based on the number of territories where FVH is positive, according to the spatial distribution in the Alberta Stroke Program Early Computed Tomography Score (ASPECTS). The prediction models were constructed according to clinical and hemodynamic parameters using multivariate logistic analysis. The DeLong test compared areas under the curves (AUCs) of the models. The multivariable logistic regression analysis showed that the National Institute of Health Stroke Scale (NIHSS) at admission, hypertension, hyperlipidemia, the ratio of wall shear stress before treatment (WSSRbefore), and difference in the ratio of wall shear stress (WSSR) were independently associated with functional outcome (all P<0.05). In the training group before treatment, the AUC of model 1a (only clinical variables) and 2a (clinical variables with addition of WSSRbefore) were 0.750 and 0.802. After treatment, the AUC of model 1b (only clinical variables) and 2b (clinical variables with addition of difference in WSSR) were 0.815 and 0.883, respectively. The AUC of models with hemodynamic parameters was significantly higher than the models based on clinical variables only (all P<0.05, DeLong test). In the internal validation group before treatment, the AUC of the model (clinical variables) was 0.782, and that of the model (clinical variables and WSSRbefore) was 0.800. After treatment, the AUC of the model (clinical variables) was 0.833, and that of the model (clinical variables and difference in WSSR) was 0.861. There were no significant differences between the good and the poor functional outcome group concerning FVHbefore scores before treatment (0.30±0.81 vs. 0.26±0.97; P=0.321) and FVHafter scores after treatment (0.08±0.39 vs. 0.00±0.00; P=0.244). Hemodynamics was associated with functional outcomes in patients with ischemic stroke attributed to atherosclerotic MCA stenosis, while FVH was not. Hemodynamic parameters were of great importance in the prediction models.

Fluid-Attenuated Inversion Recovery Vascular Hyperintensity in Cerebrovascular Disease: A Review for Radiologists and Clinicians.

Neuroradiological methods play important roles in neurology, especially in cerebrovascular diseases. Fluid-attenuated inversion recovery (FLAIR) vascular hyperintensity (FVH) is frequently encountered in patients with acute ischemic stroke and significant intracranial arterial stenosis or occlusion. The mechanisms underlying this phenomenon and the clinical implications of FVH have been a matter of debate. FVH is associated with large-vessel occlusion or severe stenosis, as well as impaired hemodynamics. Possible explanations suggested for its appearance include stationary blood and slow antegrade or retrograde filling of the leptomeningeal collateral circulation. However, the prognostic value of the presence of FVH has been controversial. FVH can also be observed in patients with transient ischemic attack (TIA), which may have different pathomechanisms. Its presence can help clinicians to identify patients who have a higher risk of stroke after TIA. In this review article, we aim to describe the mechanism and influencing factors of FVH, as well as its clinical significance in patients with cerebrovascular disease.

FLAIR vascular hyperintensity, an early sign of stroke (case report)

BackgroundGenerally, Diffusion-weighted MR imaging (DWI) is known to be more sensitive in diagnosis of acute stroke than other MR sequences. However, fluid attenuated inversion recovery (FLAIR) MR sequence founded to be sometimes more sensitive compared to DWI for the diagnosis of hyperacute stroke.Case presentationAn 84 years old female patient brought to ER by ambulance due to loss of speech, dizziness and confusion. Neurological examination showed that the patient can raise her left hand and leg while partially moving her right hand and right leg. The patient had slurred speech. Provisional diagnosis was acute stroke and the patient admitted in the hospital. Non contrast CT scan of the brain was done, was negative for stroke. Then MRI was done showed no areas of restricted diffusion at the DWI sequence or ADC map. Prominent high signal vessels at the left temporal region and on Sylvian fissure were noticed on FLAIR sequence that might have suggested early sign of ischemic vascular insult.ConclusionsArterial hyperintensity on FLAIR images can precede diffusion abnormalities and may provide a clue to the early detection of impending infarction.

FLAIR vascular hyperintensities and functional outcome in nonagenarians with anterior circulation large-vessel ischemic stroke treated with endovascular thrombectomy

To establish whether imaging assessments of irreversibly injured ischemic core and potentially salvageable penumbral volumes and collateral circulation were associated with functional outcome in nonagenarians (90 years or older) undergoing endovascular thrombectomy (EVT). Data from a prospectively maintained institutional registry of consecutive stroke patients treated with EVT from January 2012 to December 2018 were retrospectively analyzed. Functional outcome was evaluated with the modified Rankin scale (mRS) at 3 months. mRS score of 0-3 was defined as a good clinical outcome. Ischemic core and penumbral volumes were calculated using the RAPID software. Quantification of collateral circulation was performed using a fluid-attenuated inversion recovery vascular hyperintensity (FVH)-Alberta Stroke Program Early CT Score (ASPECTS) rating system. Among 85 patients (age, 92.4 ± 2.6 years; men, 30.6%) treated with EVT, good outcome (mRS 0-3) was achieved in 29 (34.1%) patients and 31 (36.5%) patients died at 90 days. The median estimated ischemic core volume was 15 mL (IQR, 7-27 mL). The median mismatch volume was 83 mL (IQR, 43-120 mL). The median FVH score was 4 (IQR, 3-4). FVH score was independently associated with good functional outcome (adjusted OR = 1.96 [95% CI, 1.16-3.32]; p = 0.01 per 1-point increase) and mortality (adjusted OR = 0.54 [95% CI, 0.34-0.85]; p = 0.007 per 1-point increase). Ischemic core and mismatch volumes were associated with neither good outcome nor mortality. In nonagenarians with anterior circulation large-vessel ischemic stroke, good collaterals as measured by the FVH-ASPECTS rating system are independently associated with improved outcomes and may help select patients for reperfusion therapy in this frail population. • Endovascular thrombectomy can allow at least 1 in 3 patients older than 90 years of age to achieve good functional outcome (modified Rankin scale of 0-3) at 3 months. • Functional outcome at 3 months is associated with pre-stroke status (number and severity of patients' comorbidities). • A higher FVH score (as reflected by higher FLAIR vascular hyperintensity [FVH]-Alberta Stroke Program Early CT Score [ASPECTS] values) is independently associated with better 3-month functional outcome and mortality in nonagenarians with anterior circulation ischemic stroke.

Ivy Sign in Moyamoya Disease: A Comparative Study of the FLAIR Vascular Hyperintensity Sign Against Contrast-Enhanced MRI.

The ability of the ivy sign on contrast-enhanced T1-weighted MR imaging (CEMR) to reflect cerebral perfusion and postoperative revascularization in Moyamoya disease remains largely unknown. We aimed to compare the capabilities of CEMR and FLAIR. CEMR, FLAIR, arterial spin-labeling, and DSA were performed in 44 patients with Moyamoya disease. The ivy sign was scored separately on CEMR and FLAIR using the Alberta Stroke Program Early CT Score. The status of leptomeningeal collaterals was scored on DSA. The postoperative Matsushima grade was evaluated at least 3 months after surgical revascularization. Scoring of the ivy sign on CEMR showed excellent interrater reliability, and FLAIR vascular hyperintensity showed moderate interrater reliability. Correlation analyses revealed that DSA scores were more consistent with the CEMR-based ivy sign score (r = 0.25, P = .03) than with FLAIR vascular hyperintensity (r = 0.05, P = .65). The CEMR-based ivy sign score was significantly correlated with CBF in late-Suzuki stage Moyamoya disease (t = -2.64, P = .02). The CEMR-based ivy sign score at baseline was significantly correlated with the postoperative Matsushima grade (r = 0.48, P = .03). In this study, CEMR outperformed FLAIR in capturing the ivy sign in Moyamoya disease. In addition, the CEMR-based ivy sign score provided adequate information on hemodynamic status and postoperative neovascularization. The current study suggested that CEMR could be considered as an alternative to FLAIR in future studies investigating leptomeningeal collaterals in Moyamoya disease.

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

Background and purposeTo evaluate relationship between fluid-attenuated inversion recovery vascular hyperintensity (FVH) after intravenous thrombolysis and outcomes in different lesion patterns on diffusion-weighted imaging (DWI).MethodsPatients with severe internal carotid or...