Hyperdense Middle Cerebral Artery Sign Research Articles

Abstract TMP50: Deep Learning for Hyperdense Middle Cerebral Artery Detection Using High Resolution CT

Introduction: While CT angiography (CTA) remains the gold-standard for non-invasive diagnosis of large-vessel occlusion (LVO), accurate identification of potential thrombectomy patients on non-contrast CT (NCCT) has many practical workflow benefits. However, current evidence suggests that the hyperdense MCA sign on NCCT is an insensitive marker of LVO. In this study, we hypothesize that high-resolution NCCT (HR-NCCT) greatly increases the sensitivity of the hyperdense MCA sign and that a deep learning model can successfully identify the majority of LVO patients on HR-NCCT. Methods: A retrospective cohort of LVO and non-LVO patients with HR-NCCT (0.5-1.0 mm slice thickness) and CTA imaging was identified. For each patient, the location of a hyperdense MCA was annotated by an expert board-certified neuroradiologist after cross-referencing both HR-NCCT and CTA data. A convolutional neural network (CNN) was developed for localization of hyperdense MCA from HR-NCCT imaging only. In brief, the CNN is a 3D contracting-expanding network (18 layers; 596,364 trainable parameters) optimized with deep supervision and class weights. All model statistics are reported after aggregating results from a five-fold cross-validation. Results: A total of 97 LVO-positive and 110 LVO-negative cases were identified. Of the LVO cases, 81.4% (79/97) contained a hyperdense MCA upon expert review. Using these 79 positive (visible dense MCA) and 110 negative cases for training, the model demonstrated an overall 90.0% accuracy in hyperdense MCA detection (92.9% sensitivity, 88.2% specificity). Overall sensitivity was similar for M1 (91.7%) and M2-M3 (94.7%) occlusions. Additionally, of the 18 LVO cases labeled without a hyperdense MCA by expert review, 5 cases were identified correctly by the model and visually confirmed to match occlusion location on CTA. Conclusion: A deep learning model can identify 80.4% of all CTA-confirmed LVO patients using only HR-NCCT, with sensitivity approaching human experts. Combined with ASPECTS evaluation, NCCT-based imaging triage alone may be sufficient to identify the majority of candidate thrombectomy patients.

Abstract TP204: Performance of Rapidai NCCT Stroke Software in Colombia's Early Stroke System: Preliminary Results

Background: Automated stroke solutions in developing countries have the potential to reduce healthcare gaps. This study assesses the performance of the RAPID NCCT Stroke module compared to local neuroradiologists’ evaluation of acute stroke. Methods: Rapid NCCT stroke is a new multi-module AI tool that simultaneously evaluates non-contrast CT scans (NCCT) for ICH (any subtype, volume >0.4 ml), the ASPECT score, and suspicion of LVO (i.e., intracranial ICA or horizontal segment of the MCA). The software determines suspicion of LVO based on an algorithm that evaluates the hyperdense MCA sign and early ischemic changes in the MCA territory. Consensus readings were defined by three blinded neuroradiologists based on a subset of Non-contrast CTs obtained between January 2013 to December 2018 at Fundacion Santa Fe De Bogota University Hospital. The overall diagnostic performance of the RAPID NCCT was compared to the assessments made by the neuroradiologists. Results: 179 total stroke cases with technically adequate NCCT scans were identified. Based on the consensus of the neuroradiologists, these cases included 151 ischemic strokes, 27 ICHs >0.4 ml, 1 ICH <0.4 ml, and 28 LVO cases (verified by CT angiography). The Rapid NCCT Stroke module demonstrated high specificity (96%), NPV (98%), and accuracy (95%) for the detection of ICH. For determining the ASPECT score, the software had a specificity of 93% and an NPV of 76%. Seventy percent of the CTA-verified LVOs were detected from NCCT alone with a specificity and NPV of 82%. Conclusions: The RAPID NCCT Stroke software displayed promising results for the early identification of ICH and characterization of ischemic strokes. The software identified 70% of the LVOs from NCCT alone. This tool can potentially enhance patient outcomes by bridging healthcare gaps in evolving stroke systems. Multicenter studies in additional Latin American countries are needed for further validation.

The hyperdense middle cerebral artery sign is an early predictor of delirium in ischemic stroke patients

The hyperdense middle cerebral artery sign is an early predictor of delirium in ischemic stroke patients

Key CT markers for predicting haemorrhagic transformation after ischaemic stroke: a prospective cohort study in China

ObjectivesLimited studies have systematically addressed the CT markers of predicting haemorrhagic transformation (HT). We aimed to (1) investigate the predictive ability of the imaging factors on multimodal CT for HT...

Abstract 256: Proposal of multimodal CT‐based scoring system in prediction of hemorrhagic transformation in acute ischemic stroke

Introduction The routinely used computed tomography (CT)‐based workup in the setting of acute ischemic stroke (AIS) includes non‐contrast brain CT, CT angiography (CTA), and CT perfusion. Several CT, CTA, CTP‐based radiological biomarkers of hemorrhagic transformation (HT) were reported. To assess the predictive value of the combined multimodal CT parameters for HT after AIS and proposal of predictive scoring scale. Methods The source images of the NCCT, CTA and CTP of 282 AIS patients involving the anterior circulation (HT = 91, non‐HT = 191) were retrospectively reviewed and the following biomarkers were recorded and analyzed: Early subtle ischemic signs, hyperdense middle cerebral artery sign (HMCAS) and Alberta Stroke Program Early CT Score (ASPECTS) < 7 in NCCT, large‐vessel occlusion (LVO), clot burden score (CBS) < 6, large‐vessel occlusion, poor collateral score (CS) and Tmax > 6 s ≥ 56.5 ml. A scoring system to predict HT based on these biomarkers was developed. Each biomarker counts for a single point with the total score ranging from 0 to 7. Results All the aforementioned multimodal CT biomarkers and the selected cut offs were significantly associated with higher HT risk. The calculated scores were statistically significant different between the HT and the non‐HT groups with AUC 0.761 (95% CI 0.703–0.819, P < 0.0000001). Rates of HT were approximately five times higher in patients with score ≥ 3. Conclusion Multimodal CT‐based scoring system may provide highly reliable predictive model of hemorrhagic transformation in acute ischemic stroke.

The risk and outcome of malignant brain edema in post-mechanical thrombectomy: acute ischemic stroke by anterior circulation occlusion

Background and purposeMalignant brain edema (MBE) occurring after mechanical thrombectomy (MT) in acute ischemic stroke (AIS) could lead to severe disability and mortality. We aimed to investigate the incidence, predictors, and clinical outcomes of MBE in patients with AIS after MT.MethodsThe clinical and imaging data of 155 patients with AIS of anterior circulation after MT were studied. Standard non-contrast CT was used to evaluate baseline imaging characteristics at admission. Clinical outcomes were measured using the 90-day modified Rankin Scale (mRS) score. Based on the follow-up CT scans performed within 72 h after MT, the patients were classified into MBE and non-MBE group. MBE was defined as a midline shift of ≥ 5 mm with signs of local brain swelling. Univariate and multivariate regression analyses were used to analyze the relationship between MBE and clinical outcomes and identify the predictors that correlate with MBE.ResultsMBE was observed in 19.4% of the patients who underwent MT and was associated with a lower rate of favorable 90-day clinical outcomes. Significant differences were observed in both MBE and non-MBE groups: baseline Alberta Stroke Program Early CT (ASPECT) score, hyperdense middle cerebral artery sign (HMCAS), baseline signs of early infarct, angiographic favorable collaterals, number of retrieval attempts, and revascularization rate. Multivariate analysis indicated that low baseline ASPECT score, absent HMCAS, angiographic poor collaterals, more retrieval attempt count, and poor revascularization independently influenced the occurrence of MBE in AIS patients with anterior circulation after MT.ConclusionMBE was associated with a lower rate of favorable 90-day clinical outcomes. Low baseline ASPECT score, absent HMCAS, angiographic poor collaterals, more retrieval attempt count and poor revascularization were independently associated with MBE after MT.

Diagnostic Accuracy of Hyperdense Artery Sign in Early Detection of Middle Cerebral Artery Infarction: A Cross-Sectional Validation Study

Background Hyperdense middle cerebral artery sign (HMCAS) on a non-enhanced multidetector computed tomography (MDCT) scan is considered an important radiological marker in detecting acute arterial thrombotic occlusion, and it is one of the earliest signs of ischemic cerebrovascular accident (CVA). This finding has been observed within 90 min of symptom onset. Modern approaches to patients with cerebral infarction emphasize early diagnosis and management. Purpose To determine the diagnostic accuracy of hyperdense artery signs in early detection of middle cerebral artery (MCA) infarction on non-contrast-enhanced MDCT scan using Magnetic Resonance Angiography (MRA) within 24 h as the gold standard for definitive diagnosis. Method A total of 140 patients aged 35–70 years, referred to the radiology department of Aga Khan University Hospital with clinical suspicion of acute cerebral infarction, were included. After clinical suspicion of acute infarction, the patient underwent an initial complete MDCT scan of the brain, which was performed using Aquilion ONE 640 slice MDCT (Toshiba Medical Systems, Japan). Consultant radiologists, with a minimum of 5 years of experience in MDCT brain imaging, interpreted the images. Follow-up examination with MRA within 24 h was performed to confirm the diagnosis of MCA infarction. Results Overall sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of HMCAS in the early detection of MCA infarction on non-contrast-enhanced MDCT scan using MRA as the gold standard for definitive diagnosis was 96.20%, 93.44%, 95.0%, 95.0%, and 95.0%, respectively. Conclusion This study concluded that the diagnostic accuracy of hyperdense artery signs in the early detection of MCA infarction on non-contrast-enhanced MDCT scans is very high.

Predictors of congruency between clinical and radiographic Oxfordshire Community Stroke Project Classification subtypes

BackgroundThe Oxfordshire Community Stroke Project (OCSP) classification has been widely used to assess ischemic stroke patients based on clinical characteristics alone. However, the correlation between the clinical presentation evaluated using OCSP and imaging findings is yet to be determined. Our study aimed to describe the baseline characteristics of the OCSP subtypes of patients admitted with ischemic stroke and evaluate the predictors of the relationship between clinical and neuroimaging findings. MethodsPatients with a confirmed diagnosis of ischemic stroke admitted to a comprehensive stroke center in Brazil between February 2015 and October 2017 were eligible for the study. All participants underwent computed tomography (CT) at admission and follow-up neuroimaging within seven days, per the institutional protocol. Trained staff classified patients according to the OCSP at hospital admission. The radiographic OCSP classification was retrospectively assessed based on the last follow-up neuroimaging by investigators unaware of the clinical classification. ResultsThe overall agreement rates ranged from 65.5% to 88.7%. Lower NIHSS scores, absent hyperdense MCA sign, higher ASPECTS, and absent brainstem symptoms were related to a higher risk of misclassification. Treatment with intravenous tPA was associated with reclassification in patients with total anterior circulation syndrome. For predicting radiographic posterior circulation involvement, vertigo (OR 2.9, 95% CI 1.7–5.1, p < 0.001) and brainstem symptoms (OR 35, 95% CI 20.5–60.2, p < 0.001) were directly associated with correct classification, but motor and higher cerebral function were not correlated. ConclusionThe clinical OCSP classification presented good congruency rates with the neuroimaging findings. However, patients with lacunar syndromes are often misclassified when radiological criteria are considered.

Predicting Penumbra Salvage and Infarct Growth in Acute Ischemic Stroke: A Multifactor Survival Game.

Effective treatment of acute ischemic stroke requires reperfusion of salvageable tissue. We investigated the predictors of penumbra salvage (PS) and infarct growth (IG) in a large cohort of stroke patients. In the ASTRAL registry from 2003 to 2016, we selected middle cerebral artery strokes <24 h with a high-quality CT angiography and CT perfusion. PS and IG were correlated in multivariate analyses with clinical, biochemical and radiological variables, and with clinical outcomes. Among 4090 patients, 551 were included in the study, 50.8% male, mean age (±SD) 66.3 ± 14.7 years, mean admission NIHSS (±SD 13.3 ± 7.1) and median onset-to-imaging-time (IQR) 170 (102 to 385) minutes. Increased PS was associated with the following: higher BMI and lower WBC; neglect; larger penumbra; absence of early ischemic changes, leukoaraiosis and other territory involvement; and higher clot burden score. Reduced IG was associated with the following: non-smokers; lower glycemia; larger infarct core; absence of early ischemic changes, chronic vascular brain lesions, other territory involvement, extracranial arterial pathology and hyperdense middle cerebral artery sign; and higher clot burden score. When adding subacute variables, recanalization was associated with increased PS and reduced IG, and the absence of haemorrhage with reduced IG. Collateral status was not significantly associated with IG nor with PS. Increased PS and reduced IG correlated with better 3- and 12-month outcomes. In our comprehensive analysis, multiple factors were found to be responsible for PS or IG, the strongest being radiological features. These findings may help to better select patients, particularly for more aggressive or late acute stroke treatment.

Functional and technical outcomes in acute ischemic stroke patients with hyperdense middle cerebral artery sign treated with endovascular thrombectomy.

The hyperdense middle cerebral artery sign (HMCAS) is observed in a proportion of patients with acute ischemic stroke (AIS). This sign reflects the presence of an intravascular thrombus rich in red blood cells. Several studies have demonstrated that HMCAS increases the risk of poor outcomes in AIS patients treated with IV thrombolysis or no reperfusion therapy; however, whether HMCAS predicts a poor outcome in patients treated with endovascular thrombectomy (EVT) is less clear. We aimed to evaluate the functional outcome by the modified Rankin scale (mRS) at 90 days and technical challenges in patients with HMCAS undergoing EVT. We studied 143 consecutive AIS patients with middle cerebral artery M1 segment or internal carotid artery + M1 occlusions who underwent EVT. There were 73 patients (51%) with HMCAS. Patients with HMCAS had a higher frequency of cardioembolic stroke (p = 0.038); otherwise, no other baseline difference was observed. No differences in functional outcomes (mRS) at 90 days (p = 0.698), unfavorable outcomes (mRS > 2) (p = 0.929), frequency of symptomatic intracranial hemorrhage (p = 0.924), and mortality (mRS-6) (p = 0.736) were observed between patients with and without HMCAS. In patients with HMCAS, EVT procedures were 9 min longer, requiring a higher number of passes (p = 0.073); however, optimal recanalization scores (modified thrombolysis in cerebral infarction: 2b-3) were equally achieved by both groups. Patients with HMCAS treated with EVT do not have a worse outcome at 3 months compared with no-HMCAS patients. Patients with HMCAS required a greater number of thrombus passes and longer procedure times.

Proposal of multimodal computed tomography-based scoring system in prediction of hemorrhagic transformation in acute ischemic stroke.

The routinely used computed tomography (CT)-based workup in the setting of acute ischemic stroke (AIS) includes non-contrast brain CT, CT angiography (CTA), and CT perfusion. Several CT, CTA, CTP-based radiological biomarkers of hemorrhagic transformation (HT) were reported. To assess the predictive value of the combined multimodal CT parameters for HT after AIS and proposal of predictive scoring scale. The source images of the NCCT, CTA and CTP of 282 AIS patients involving the anterior circulation (HT = 91, non-HT = 191) were retrospectively reviewed and the following biomarkers were recorded and analyzed: Early subtle ischemic signs, hyperdense middle cerebral artery sign (HMCAS) and Alberta Stroke Program Early CT Score (ASPECTS) < 7 in NCCT, large-vessel occlusion (LVO), clot burden score (CBS) < 6, large-vessel occlusion, poor collateral score (CS) and Tmax > 6s ≥ 56.5ml. A scoring system to predict HT based on these biomarkers was developed. Each biomarker counts for a single point with the total score ranging from 0 to 7. All the aforementioned multimodal CT biomarkers and the selected cut offs were significantly associated with higher HT risk. The calculated scores were statistically significant different between the HT and the non-HT groups with AUC 0.761 (95% CI 0.703-0.819, P < 0.0000001). Rates of HT were approximately five times higher in patients with score ≥ 3. Multimodal CT-based scoring system may provide highly reliable predictive model of hemorrhagic transformation in acute ischemic stroke.

Interexpert agreement between neuroradiologists in the diagnosis of middle cerebral artery stroke by computed tomography

Background. To evaluate the diagnostic accuracy of radiologists with a wide range of experience and training in emergency neuroradiology and other specialty hospitals, as well as the level of inter-experts’ agreement regarding CT signs of ischemic stroke.Material and methods. Our study included a retrospective cohort of 100 patients who underwent NCCT, CT angiography (mCTA) and CT perfusion in St. Petersburg clinical hospital. Fifty patients had confirmed middle cerebral artery ischemic stroke. The study also randomly included fifty patients in whom this diagnosis was excluded, including on the basis of dynamic follow-up as part of further clinical evaluation and follow-up CT scan of the brain. All 100 CT were reviewed by 21 radiologists who independently assessed each study for CT evidence of ischemic stroke. Statistical analysis included the Kappa-Fleiss coefficient ( ) calculation of agreement for each sign of ischemic stroke, specificity, sensitivity, and accuracy of detection of these changes.Results. The staff radiologist’s mean experience in emergency neuroradiology affects both diagnostic performance and consistency for detection of most CT features of ischemic stroke. At the same time, experience does not affect the diagnostic efficiency of radiologists with no experience in stroke assessment. The most highly specific and reproducible sign of ischemic stroke was the hyperdense middle cerebral artery sign, and the most ambiguous diagnostic sign was the gyral effacement. At the same time, all radiologists, regardless of length of service record and experience in emergency neuroradiology, are prone to over-diagnosis.Conclusion. Further search for tools and solutions is needed to level out interexpert variability regarding assessment of ischemic CT signs, since this problem has high clinical importance.

Abstract WMP95: External Validation Of Acute Atherosclerotic Ischemic Stroke Radiological Markers

Introduction: Intracranial atherosclerosis-related acute large vessel occlusion (ICAS-LVO) is the dominant cause of acute middle cerebral artery (MCA) occlusions that can be passed with wire or microcatheter but cannot be completely opened (5-15% of all middle cerebral artery (MCA) infarcts). The major challenge of ICAS-LVO is the tendency of reocclusion or cause a residual, fixed severe stenosis rendering the vessel with suboptimal revascularization. These patients carry a poor functional outcome and high mortality despite mechanical thrombectomy (MT). We aimed to externally validate three preidentified markers of ICAS-LVO on early non-contrast computed tomography (NCCT) and CT Angiogram (absent hyperdense MCA sign (HMCAS), Hounsfield measurements (HU ratio≤1.1 and Delta HU&lt;6) and CTA truncal occlusion). Methods: We conducted a retrospective analysis of 77 consecutive patients presenting with acute M1 occlusions undergoing MT. Based on our previous observational experiences, NCCT and CTA patterns that had been associated with ICAS-LVO included the absent HMCAS, HU ratio and Delta HU between site of occlusion and contralateral MCA and CTA truncal occlusion. ICAS-LVO was identified if an occlusion was difficult to cross, had tendency to reocclude after successful recanalization or demonstrated residual fixed severe stenosis. These markers were also compared with reperfusion rates and functional outcomes at 3 months. Results: Out of 77 patients, 13 (16%) had suspected ICAS-LVO. Absent HMCAS had a sensitivity of 91% and specificity of 90% (AUC 0.91), HU ratio ≤1.1 and delta HU &lt;6 had sensitivity of 100% and specificity of 98% (AUC 0.992) and CTA truncal occlusion had sensitivity of 91% and specificity of 97% (AUC 0.943), in predicting ICAS-LVO. These radiological markers were also significantly associated with unsuccessful reperfusion (TICI 0-2a) and poor functional outcomes (mRS&gt;2) at 3 months. Conclusion: Initial non-contrast CT and CTA markers are highly sensitive and specific in predicting atherosclerotic M1 occlusions and significantly associated with failed reperfusion, and poor functional outcomes after mechanical thrombectomy.

Prognostic value of radiomics-based hyperdense middle cerebral artery sign for patients with acute ischemic stroke after thrombectomy strategy.

The purpose of this study was to evaluate the prognostic value of radiomics-based hyperdense middle cerebral artery sign (HMCAS) for patients with acute ischemic stroke (AIS) after mechanical thrombectomy (MT) and to establish prediction models to identify patients who may benefit more from MT. In this retrospective study, a total of 102 consecutive patients who presented with HMCAS on non-contrast computed tomography (NCCT) at admission and underwent MT in our hospital between January 2019 and December 2020 were recruited. Among them, 46 experienced favorable outcomes (modified Rankin Scale [mRS] ≤ 2) at 3 months of follow-up. All patients were categorized into two sets, namely, the training set (n = 81) and the test set (n = 21). Radiomics features (RFs) and clinical features (CFs) in the training set were selected by statistical analysis to create models. The models' discriminative ability was quantified using the area under the curve (AUC) and confirmed by decision curve analyses. The prediction model established using CFs before MT includes baseline National Institutes of Health Stroke Scale (NIHSS) and neutrophil-to-lymphocyte ratio (NLR) [AUC [95% confidence interval (CI)] = 0.596 (0.312-0.881)]. A total of 1,389 RFs were extracted from each hyperdense territory and 8 RFs were left to build the radiomics model [RM; AUC (95%CI) = 0.798 (0.598-0.998)]. The model using preoperative CFs and RFs showed good performance [AUC (95%CI) = 0.817 (0.625-1.000)]. The models using post-operative CFs alone [AUC (95%CI) = 0.856 (0.685-1.000)] or post-operative CFs with RFs [AUC (95%CI) = 0.894 (0.757-1.000)] also showed good discrimination. The radiomics-based HMCAS might be a promising tool to predict the prognoses of patients with AIS after MT.

Usefulness of carotid duplex ultrasonography in predicting residual large-vessel occlusions after intravenous recombinant tissue plasminogen activator therapy in patients with acute ischemic stroke.

Endovascular therapy (EVT) preceded by intravenous thrombolysis with recombinant tissue plasminogen activator (iv-rtPA) has been established as a standard treatment in patients with stroke caused by large-vessel occlusion (LVO). Primary stroke centers without EVT competence need to identify patients with residual LVO after iv-rtPA therapy and transport them to an EVT-capable facility. Carotid ultrasonography (CUS) is easily applicable at bed side and useful for detecting extra- and intracranial LVO. This study aimed to determine whether CUS findings at admission are useful to predict patients with residual LVO after iv-rtPA. Patients scheduled to undergo iv-rtPA for acute cerebral infarction were registered. Before iv-rtPA, they underwent CUS, followed by CTA or MRA evaluation within 6h after iv-rtPA. A model that can achieve 100% sensitivity for detecting residual LVO after iv-rtPA was studied. This study included 68 of 116 patients treated with iv-rtPA during the study period. National Institutes of Health Stroke Scale (NIHSS) score (cutoff value = 10) on arrival, hyperdense MCA sign on non-contrast CT, end-diastolic (ED) ratio on CUS, and eye deviation were significantly different between patients with residual LVO after iv-rtPA and those without. If any of these clinical features are positive in the screening test, residual LVO could be predicted with 100% sensitivity, 50% specificity, 64% positive predictive value, and 100% negative predictive value. Prediction of residual LVO with 100% sensitivity may be feasible by adding CUS to NIHSS score > 10, the presence of eye deviation, and hyperdense MCA sign.

Proximal hyperdense middle cerebral artery sign is associated with increased risk of asymptomatic hemorrhagic transformation after endovascular thrombectomy: a multicenter retrospective study

ObjectiveTo investigate whether hyperdense middle cerebral artery sign (HMCAS) on pretreatment no-contrast CT (NCCT) is associated with hemorrhagic transformation (HT) after endovascular thrombectomy (EVT).MethodsPatients with acute middle cerebral artery (MCA) occlusion who received EVT in three comprehensive hospitals were retrospectively evaluated. They were divided into four groups based on the presence or absence of HMCAS and corresponding CTA findings, among whom differences were compared. Univariate and multivariate logistic regression analyses were performed to investigate the association between HMCAS and HT and its subtypes.Results318 patients were included, among whom 149 (46.9%) had HMCAS. Patients in the proximal positive HMCAS group had higher National Institute of Health Stroke Scale scores and lower Alberta Stroke Program Early CT Scores (ASPECTS) than those in the proximal negative HMCAS group. The rate of HT was higher in the proximal positive HMCAS group than that in the proximal negative HMCAS group. In multivariate logistic regression analysis, the proximal HMCAS were independently associated with HT (adjusted OR = 2.073, 95% CI 1.211–3.551, p = 0.008) and aHT (adjusted OR = 2.271, 95% CI 1.294–3.986, p = 0.004), but not with sHT. Patients who developed HT, including aHT and sHT, had a lower rate of good outcome.ConclusionProximal HMCAS on initial NCCT was independently associated with aHT in patients who received EVT for acute MCA occlusion. Both aHT and sHT had a detrimental effect on clinical outcome.

Hyperdense middle cerebral artery sign predicts favorable outcome in patients undergoing mechanical thrombectomy.

Non-contrast computer tomography detects the presence of hyperdense middle cerebral artery sign (HMCAS). Studies on the prognostic value of HMCAS among patients undergoing mechanical thrombectomy (MT) are conflicting. A retrospective analysis of consecutive patients with acute ischemic stroke due to middle cerebral artery occlusion, presenting with or without HMCAS, who underwent MT, was performed. We enrolled 191 patients (HMCAS +, n = 140; HMCAS -, n = 51). Prevalence of successful recanalization was significantly higher in patients with HMCAS than in those without HMCAS (92.1% versus 74.5%, p = 0.001). Patients with HMCAS had a better clinical outcome than those HMCAS - (54.3% versus 37.3%, p = 0.037, for three-month favorable outcome; 62.9% versus 39.3%, p = 0.004, for major neurological improvement at discharge; 8.6% versus 19.6%, p = 0.035, for in-hospital mortality; 14.3% versus 27.5%, p = 0.035, for intracranial hemorrhage; 2.9% versus 17.6%, p = 0.001, for symptomatic intracranial hemorrhage). Multivariate analyses confirmed that HMCAS represents an independent predictor of three-month favorable outcome (OR 2.48, 95% CI 1.10-5.58, p = 0.028), major neurological improvement at discharge (OR 2.40, 95% CI 1.09-5.20, p = 0.030), in-hospital mortality (OR 0.29, 95% CI 0.010-0.81, p = 0.018), presence of ICH (OR 0.49, 95% CI 0.25-0.97, p = 0.042) and presence of SICH (OR 0.16, 95% CI 0.04-0.63, p = 0.009). HMCAS presence predicts favorable outcome in patients undergoing MT. This result may indicate that hyperdense clots are more likely to respond to MT than isodense ones. This effect is mediated by reduction in hemorrhagic transformation.

Is Composition of Brain Clot Retrieved by Mechanical Thrombectomy Associated with Stroke Aetiology and Clinical Outcomes in Acute Ischemic Stroke?-A Systematic Review and Meta-Analysis.

Background: Brain clots retrieved following endovascular thrombectomy in acute ischemic stroke patients may offer unique opportunities to characterise stroke aetiology and aid stroke decision-making in select groups of patients. However, the evidence around the putative association of clot morphology with stroke aetiology is limited and remains inconclusive. This study aims to perform a systematic review and meta-analysis to delineate the association of brain clot composition with stroke aetiology and post-reperfusion outcomes in patients receiving endovascular thrombectomy. Methods: The authors conducted a systematic literature review and meta-analysis by extracting data from several research databases (MEDLINE/PubMed, Cochrane, and Google Scholar) published since 2010. We used appropriate key search terms to identify clinical studies concerning stroke thrombus composition, aetiology, and clinical outcomes, in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Results: The authors identified 30 articles reporting on the relationship between stroke thrombus composition or morphology and aetiology, imaging, or clinical outcomes, of which 21 were included in the meta-analysis. The study found that strokes of cardioembolic origin (SMD = 0.388; 95% CI, 0.032–0.745) and cryptogenic origin (SMD = 0.468; 95% CI, 0.172–0.765) had significantly higher fibrin content than strokes of non-cardioembolic origin. Large artery atherosclerosis strokes had significantly lower fibrin content than cardioembolic (SMD = 0.552; 95% CI, 0.099–1.004) or cryptogenic (SMD = 0.455; 95% CI, 0.137–0.774) strokes. Greater red blood cell content was also significantly associated with a thrombolysis in cerebral infarction score of 2b–3 (SMD = 0.450; 95% CI, 0.177–0.722), and a positive hyperdense middle cerebral artery sign (SMD = 0.827; 95% CI, 0.472–1.183). No significant associations were found between red blood cell, platelet, or white blood cell content and aetiology, or between clot composition and bridging thrombolysis. Conclusions: This meta-analysis found that fibrin composition is significantly higher in strokes of cardioembolic and cryptogenic origin, and that red blood cell content is positively associated with the hyperdense middle cerebral artery sign and better reperfusion outcomes. Important advances to stroke clinical workup can be derived from these findings, in which many aspects of stroke workflow remain to be optimised. As data are still limited in terms of the association of various thrombus components with stroke aetiology as well as a standardised method of analysis, further studies are required to validate these findings to guide their use in clinical decision-making.

Prediction model of early biomarkers of massive cerebral infarction caused by anterior circulation occlusion: Establishment and evaluation

ObjectiveThe purpose of this study is to establish and evaluate an early biomarker prediction model of massive cerebral infarction caused by anterior circulation occlusion.MethodsOne hundred thirty-four patients with acute cerebral infarction from January 2018 to October 2020 were selected to establish the development cohort for the internal test of the nomogram. Ninety-one patients with acute cerebral infarction hospitalized in our hospital from December 2020 to December 2021 were constituted the validation cohort for the external validation. All patients underwent baseline computed tomography (CT) scans within 12 h of onset and early imaging signs (hyperdense middle cerebral artery sign, obscuration of the lentiform nucleus, insular ribbon sign) of acute cerebral infarction were identified on CT by two neurologists. Based on follow-up CT images, patients were then divided into a massive cerebral infarction group and a non-massive cerebral infarction group. The nomogram model was constructed based on logistic regression analysis with R language. The nomogram was subsequently validated in an independent external validation cohort. Accuracy and discrimination of the prediction model were evaluated by a calibration chart, receiver operating characteristic (ROC) curve, and decision curve.ResultsThe indicators, including insular ribbon sign, reperfusion therapy, National Institutes of Health Stroke Scale (NHISS) score, previous cerebral infarction, and atrial fibrillation, were entered into the prediction model through binary logistic regression analysis. The prediction model showed good predictive ability. The area under the ROC curve of the prediction model was 0.848. The specificity, sensitivity, and Youden index were 0.864, 0.733, and 0.597, respectively. This nomogram to the validation cohort also showed good discrimination (AUC = 0.940, 95% CI 0.894–0.985) and calibration.ConclusionDemonstrating favorable predictive efficacy and reproducibility, this study successfully established a prediction model of CT imaging signs and clinical data as early biomarkers of massive cerebral infarction caused by anterior circulation occlusion.

Does thrombus imaging characteristics predict the degree of recanalisation after endovascular thrombectomy in acute ischaemic stroke?

BackgroundIdentification of computed tomography (CT) thrombus imaging characteristics can predict the degree of recanalization and outcome after endovascular thrombectomy (EVT) in patients with acute ischaemic stroke and large vessel occlusion. AimWe analyzed the thrombus imaging characteristics and procedural factors and correlated with the degree of recanalization and functional outcome after EVT. MethodsWe evaluated the thrombus imaging characteristics (hyperdense MCA sign, thrombus location, length and thrombus permeability) from thin slice CT and CT angiogram. In addition, groin to recanalization time, number of passes, and EVT technique were documented. The primary outcome was degree of recanalization (mTICI score) and secondary outcome was modified Rankin scale (mRS) at 3 months. ResultsThe mean age of 102 patients was 60.5±11.8 years. Patients with hyperdense MCA sign (90 % vs 75%, p=0.07) and permeable thrombus (86 % vs 70 %, p=0.09) had good recanalization (mTICI grade 2b,2c or 3). The requirement of <3 passes (90 % vs 62 %, p= 0.001) was associated with good recanalization. Multiple logistic regression analysis showed thrombus permeability (OR 5.9; 95% CI 1.3-26.6, p=0.02), use of stent retreiver alone (without aspiration) (OR 5.4; 95% CI 1.3-22.5, p=0.02) and a puncture to recanalization ≤60 minutes (OR 7.9; 95% CI 1.7-36.8; p=0.008) were associated with good recanalization. The requirement of ≥3 passes was associated with poor functional outcome (OR 3.4;95% CI 1.2-9.8; p=0.02). ConclusionsThrombus permeability was a predictor of successful recanalization after EVT. The requirement of three or more passes during EVT was associated with poor recanalization and poor functional outcome.