Setting Of Acute Ischemic Stroke Research Articles

Dynamic Perviousness Has Predictive Value for Clot Fibrin Content in Acute Ischemic Stroke.

Dynamic perviousness is a novel imaging biomarker, with clot density measurements at multiple timepoints to allow longer contrast to thrombus interaction. We investigated the correlations between dynamic perviousness and clot composition in the setting of acute ischemic stroke. Thirty-nine patients with large vessel occlusion (LVO) undergoing mechanical thrombectomy (MT) were analyzed. Patients received a three-phase CT imaging pre-thrombectomy and histopathological analysis of retrieved clots. Clot densities for every phase and change in densities between phases were calculated, leading to four patterns of dynamic perviousness: no contrast uptake, early contrast uptake with and without washout and late uptake. Clots were categorized into three groups based on dominant histologic composition: red blood cell (RBC)-rich, fibrin/platelet-rich and mixed. Clot composition was correlated with dynamic perviousness using the Kruskal-Wallis test and Pearson's correlation analysis. The dynamic perviousness categories showed a significant difference between fibrin-rich clots when compared to RBC-rich plus mixed groups. The uptake without washout category had significantly fewer fibrin clots compared to the uptake with washout (p = 0.036), and nearly significantly fewer fibrin clots when compared to the no uptake category (p = 0.057). Contrast uptake with different patterns of contrast washout showed significant differences of the likelihood for fibrin-rich clots.

Utility of A2L2 score in acute ischemic stroke patient triage: the "H.uni" experience.

Two or more National Institutes of Health Stroke Scale (NIHSS) points on each motor items (A2L2 score) have shown good accuracy in predicting large vessel occlusion (LVO) in the prehospital setting of acute ischemic stroke (AIS) care. We aimed to study this score for LVO prediction in our stroke network and predictors of poor outcome (PO) after mechanical thrombectomy (MT). From our Safe Implementation of Thrombolysis in Stroke (SITS) registry including patients receiving reperfusion therapy for AIS, we retrospectively computed the A2L2 score from the admission NIHSS to test the diagnostic accuracy for LVO prediction. Multivariable analysis for independent predictors of LVO on the entire cohort and PO from patients with LVO were performed. From the 853 patients with AIS (67% LVO), A2L2 was positive in 52%. A2L2 score (Odds ratio [OR] 4.6;95%CI 3.36-6.34), smoking (OR 2.1;95%CI 1.14-3.85), atrial fibrillation (OR 1.6;95%CI1.1-2.4) and younger age (OR 0.98;95%CI0.97-0.99) were independent predictors of LVO. A2L2 score showed 82%/49% positive/negative predictive values with 66% accuracy (64%/72% sensitivity/specificity) for LVO prediction. Age (OR 1.05;95%CI 1.03-1.07), atrial fibrillation (OR 4.85;95%CI 1.5-15.7), diabetes (OR 2.62;95% CI 1.14-6.05), dyslipidemia (OR 2;95% CI 1.04-3.87), A2L2 score (OR 2.68;95% CI 1.45-4.98), longer onset-to-groin time (OR 1.003;95% CI 1.001-1.01), MT procedure (OR 1.01;95%CI 1.003-1.02) general anaesthesia (OR 2.06;95% CI 1.1-3.83) and symptomatic intracranial hemorrhage (OR 12.10;95%CI 3.15-46.44) were independent predictors of PO. A2L2 score independently predicted LVO and PO after MT. Patient characteristics and procedural factors determined PO of LVO patients after MT.

Incidence and predictors of intracranial hemorrhage after intravenous thrombolysis with tenecteplase.

Despite its increasing use, there are limited data on the risk of intracranial hemorrhage (ICH) after intravenous thrombolysis with tenecteplase in the setting of acute ischemic stroke. Our aim was to investigate the incidence and predictors of ICH after tenecteplase administration. We reviewed data from the prospective ongoing multicenter TETRIS (Tenecteplase Treatment in Ischemic Stroke) registry. Patients with available day-1 imaging were included in this study. Clinical, imaging and biological variables were collected. Follow-up imaging performed 24 h after IVT was locally reviewed by senior neuroradiologists and neurologists. The incidence of parenchymal hematoma (PH) and any ICH were investigated. Potential predictors of PH and any ICH were assessed in multivariable logistic regressions. Subgroup analyses focusing on patients intended for endovascular treatment were performed. PH and any ICH occurred in 126/1321 (incidence rate: 9.5%, 95% CI 8.1-11.2) and 521/1321 (39.4%, 95% CI 36.8-42.1) patients, respectively. Symptomatic ICH was observed in 77/1321 (5.8%; 95% CI 4.7-7.2). PH occurrence was significantly associated with poorer functional outcomes (p < 0.0001) and death (p < 0.0001) after 3 months. Older age (aOR = 1.03; 95% CI 1.01-1.05), male gender (aOR = 2.07; 95% CI 1.28-3.36), a history of hypertension (aOR = 2.08; 95% CI 1.19-3.62), a higher baseline NIHSS (aOR = 1.07; 95% CI 1.03-1.10) and higher admission blood glucose level (aOR = 1.12; 95% CI 1.05-1.19) were independently associated with PH occurrence. Similar associations were observed in the subgroup of patients intended for endovascular treatment. We quantified the incidence of ICH after IVT with tenecteplase in a real-life prospective registry and determined independent predictors of ICH. These findings allow to identify patients at high risk of ICH.

The pEGASUS-HPC stent system for intracranial arterial stenosis: a single-center case series

BackgroundIntracranial arterial stenting is a technique for the treatment of symptomatic stenosis. In this single-center retrospective case series we evaluated a novel low profile laser-cut stent with an antithrombogenic hydrophilic...

Endovascular Thrombectomy for Carotid Pseudo-Occlusion in the Setting of Acute Ischemic Stroke: A Comparative Systematic Review and Meta-analysis.

The effective treatment for patients with acute ischemic stroke (AIS) with cervical internal carotid pseudo-occlusion (cICA-PO) requires comprehensive research on the safety and outcomes of endovascular thrombectomy (EVT). However, there are limited data available, highlighting the need for further research to ensure better treatment strategies and improve the quality of care for these patients. This study aims to assess the management and outcomes in this population group compared with patients with true carotid occlusion. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines, a comprehensive systematic review was conducted by using PubMed, Embase, Web of Science, and Scopus from database inception to November 2023. The size of the included studies ranged from 16 patients to 146 patients. Through the 4 full-text articles, a total of 259 patients were collected. We compared outcomes between patients with cICA-PO compared with patients with true carotid occlusions undergoing EVT due to AIS. We excluded studies with patients with carotid pseudo-occlusion without stroke, review articles, duplicate studies, overlapped data that included the same patients presented in another included study, case reports, case series with fewer than 5 patients, and meeting abstracts that did not contain the outcomes of interest. We did not pose any limitations regarding sample size or patient characteristics. We utilized the R statistical software (V.4.3.1; R package meta) to conduct the analysis of all the data obtained. We calculated the OR for binary variables, and the corresponding 95% CI. To synthesize the data, random-effect models, as well as forest plots were generated to visually represent the synthesis of the data. Additionally, we assessed heterogeneity by using Cochran Q and I 2 tests. A P value < .05 for the Q statistic or I 2 more than 50% suggests notable heterogeneity. Based on a small number of studies (<10), the assessment of publication bias could not be reliably performed. This meta-analysis encompassed data from 4 studies. Patients with cICA-PO and AIS who underwent EVT (n = 135) exhibited lower rates of functional independence (OR = 0.35; 95% CI, 0.20-0.61; P < .001) compared with patients with true occlusions (n = 103), as well as successful recanalization rates (OR = 0.39; 95% CI, 0.20-0.74; P = .004). In addition, the cICA-PO group experienced higher mortality and symptomatic intracranial hemorrhage (sICH) compared with the group with true carotid occlusions (OR = 2.62; 95% CI, 0.21-7.24; and OR = 2.23; 95% CI, 1.00-4.95; P = .049, respectively). Individual patient data were not available. Studies were a retrospective design and some of the studies had small sample sizes. The included studies in our meta-analysis did not exclude patients with tandem occlusions that might influence the results of the comparison. Compared with patients with true carotid occlusion, the cICA-PO group with AIS undergoing EVT presented poor outcomes with lower functional independence and successful recanalization, as well as higher sICH and mortality rates.

Abstract WP95: The Effectiveness of Remote Informed Consent for Clinical Intervention in the Setting of Acute Ischemic Stroke

Background: Informed consent is an essential part of current medical practice which protects the patient’s right to make an informed decision with sufficient understanding of the risks and the benefits of any medical intervention. Because of the need to provide care quickly, consent is often obtained remotely in acute ischemic stroke. Currently, to our knowledge, no study has provided a direct measurement of effectiveness of remote consent compared to in-person consent. In this study, we surveyed those providing consent for thrombolysis and thrombectomy for satisfaction with the consent process. We also compared in person and remote consent for effectiveness in understanding of the intervention. Methods: We conducted post-consent surveys of the person consenting to either thrombolysis or thrombectomy (patient or their legally authorized representative). Surveys assessed satisfaction with the consent process including if the explanation of the procedure was clear and if they had comfortable level of understanding. Survey also included self- and objective assessments of the information provided. Patients who received thrombolysis via wake-up protocol, or as part of another research study, were excluded. Results: A total of 86 surveys assessing 61 remote and 25 in-person consents were analyzed. The in person consents were 56% thrombectomy, while remote consents were 97% thrombectomy. Both in-person and remote groups had high satisfaction rate (9.72/10 vs 9.44/10, P = 0.301) and high self-assessment of understanding (2.56/3 vs 2.74/3, P = 0.11). Objective assessment testing consenter’s knowledge of the procedure showed slightly lower performance for in-person consent, although this was statistically not significant (91% vs 93%, P= 0.17). Further analysis excluding self-consents showed no difference in the two groups (92% vs 94%, P = 0.77). Conclusion: Our observational study showed that patient and legal authorized representatives had a similarly satisfactory experience and understanding when consenting to thrombolysis/thrombectomy when consented in person compared to remote consent.

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) &lt; 7 in NCCT, large‐vessel occlusion (LVO), clot burden score (CBS) &lt; 6, large‐vessel occlusion, poor collateral score (CS) and Tmax &gt; 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 &lt; 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.

Analyzing the Role of Arterial Spin Labelling in Patients Undergoing Endovascular Thrombectomy for Large Vessel Occlusion—a Prospective Single Center Study

Acute stroke is one of the leading causes of death globally. Imaging remains the most common modality to diagnose and predict outcomes in patients with stroke. Conventionally, computed tomography (CT) was the preferred choice; however, imaging has expanded to include newer modalities such as Dynamic Susceptibility Contrast (DSC), Dynamic Contrast-Enhanced MRI (DCE), and Arterial Spin Labelling MRI. An alternative method of assessing perfusion, ASL uses the spins of endogenous water protons as a tracer rather than administering a contrast agent. In this manner, endogenous water in the arterial blood is labelled electromagnetically and employed as a freely diffusible tracer. ASL, as opposed to CT, DSC or DCE, allows estimation of cerebral blood flow without exposure to radiation or the administration of contrast material, which is advantageous for patients with impaired renal function or repetitive perfusion imaging. Thus a prospective study was conducted to explore the use of Arterial Spin Labelling MRI in the setting of acute ischemic stroke in both pre and post-thrombectomy patients. Our study is significant as there are no existing prospective studies comparing the cerebral perfusion measured using ASL with neurological outcomes.

CO97 Risk Factors, Presentation and Outcome in Acute Ischemic Stroke According to Social Position Indicators in Patients Hospitalized in a Referral Center in Bogotá 2011-2019

As stroke treatment is time-dependent, it challenges the social and demographic context of patients for timely consultation and effective access to reperfusion therapies. The aim of this study was to relate indicators of social position to cardiovascular risk factors, time of arrival, access to reperfusion therapy and mortality in the setting of acute ischemic stroke.

Exploring the Utility of Autonomic Nervous System Evaluation for Stroke Prognosis.

Stroke is a major cause of functional disability and is increasing in frequency. Therefore, stroke prognosis must be both accurate and timely. Among other biomarkers, heart rate variability (HRV) is investigated in terms of prognostic accuracy within stroke patients. The literature research of two databases (MEDLINE and Scopus) is performed to trace all relevant studies published within the last decade addressing the potential utility of HRV for stroke prognosis. Only the full-text articles published in English are included. In total, forty-five articles have been traced and are included in the present review. The prognostic value of biomarkers of autonomic dysfunction (AD) in terms of mortality, neurological deterioration, and functional outcome appears to be within the range of known clinical variables, highlighting their utility as prognostic tools. Moreover, they may provide additional information regarding poststroke infections, depression, and cardiac adverse events. AD biomarkers have demonstrated their utility not only in the setting of acute ischemic stroke but also in transient ischemic attack, intracerebral hemorrhage, and traumatic brain injury, thus representing a promising prognostic tool whose clinical application may greatly facilitate individualized stroke care.

All Trans Retinoic Acid: A Cerebral Friend or Foe? (P3-5.002)

<h3>Objective:</h3> NA <h3>Background:</h3> All-trans retinoic acid (ATRA) is an initial treatment for acute promyelocytic leukemia (APL). Studies suggest that ATRA has neuroprotective effects since it reduces atherosclerosis and neural inflammation. We present a case series of patients that developed acute recurrent ischemic strokes and demonstrated rapid progression of intracranial and extracranial stenosis in the setting of ATRA therapy. <h3>Design/Methods:</h3> NA <h3>Results:</h3> <h3>Case 1:</h3> A 47-year-old female with a history of hypertension presented with symptoms concerning for myocardial infarction, deep venous thrombosis, and thrombocytopenia which led to a diagnosis of APL. She was treated with ATRA and two days later developed left gaze deviation, facial droop, and left hemiparesis. Vessel imaging revealed a right middle cerebral artery (MCA) occlusion. Despite successful thrombectomy, the patient continued to decline. Repeat imaging showed re-occlusion of the right MCA as well as a new left MCA infarct. She later developed diffuse cerebral edema and fatal herniation. <h3>Case 2:</h3> A 41-year-old female with a history of hypertension and APL treated with ATRA had multiple recent strokes involving bilateral frontal, left occipital and watershed territories. Vessel imaging during the first admission did not show any stenosis. Over the course of the next seven months, she had multiple admissions for recurrent strokes with rapid progression and worsening of her intracranial stenosis despite dual antiplatelet and statin therapy. Cerebrospinal fluid analysis including cell count, protein, cytology and flow cytometry was unremarkable. She subsequently developed extensor posturing with paraparesis due to malignant cerebral edema and died. <h3>Conclusions:</h3> The underlying mechanism of accelerated vessel stenosis in the above cases is unknown. Further research should explore whether ATRA use in APL is indeed associated with the progression and/or poor clinical outcomes in the setting of acute ischemic stroke. Clinicians should remain vigilant about the concomitant use of ATRA in patients with a history of vascular risk factors. <b>Disclosure:</b> Mannyam, MD (Jackson, MS); Maryam

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.

Thrombectomy Using the EmboTrap Clot-Retrieving Device for the Treatment of Acute Ischemic Stroke: A Glimpse of Clinical Evidence.

The EmboTrap Recanalization Device is a novel stent retriever for thrombectomy in the setting of acute ischemic stroke due to large-vessel occlusion. Our aim was to summarize the safety and efficacy of the EmboTrap Recanalization Device in acute ischemic stroke-large-vessel occlusion through a systematic review and meta-analysis. Medline, EMBASE, the Cochrane Library, Web of Science, and Google Scholar were searched up to April 2022. Nine observational studies using the EmboTrap Recanalization Device were selected. We adapted effect size with 95% CIs for dichotomous data. P value <.05 was statistically significant. The estimated rate of successful recanalization (modified TICI 2b-3) was 90% (95% CI, 86%-95%; I 2 = 82.4%); 90-day favorable outcome (mRS 0-2), 53% (95% CI, 42%-63%; I 2 = 88.6%); modified first-pass effect, 43% (95% CI, 35%-51%; I 2 = 63.7%); and first-pass effect, 36% (95% CI, 29%-46%; I 2 = 10.7%). The rate of any intracerebral hemorrhage was 19% (95% CI, 16%-22%; I 2 = 0.0%); symptomatic intracerebral hemorrhage, 5% (95% CI, 1%-8%; I 2 = 84.6%); and 90-day mortality, 14% (95% CI, 9%-19%; I 2 = 79.3%). Subgroup analysis showed higher rates of complete recanalization for EmboTrap II than for the EmboTrap System. The included studies are single-arm without direct comparison with other stent retrievers. Some of the studies recruited had a small sample size and were limited by the retrospective study design. In addition, the uncertain heterogeneity among studies was high. The EmboTrap Recanalization Device is safe and efficient in treating acute ischemic stroke due to large-vessel occlusion.

Three-Dimensional Constructive Interference in Steady State (3D CISS) Imaging and Clinical Applications in Brain Pathology.

Three-dimensional constructive interference in steady state (3D CISS) is a steady-state gradient-echo sequence in magnetic resonance imaging (MRI) that has been used in an increasing number of applications in the study of brain disease in recent years. Owing to the very high spatial resolution, the strong hyperintensity of the cerebrospinal fluid signal and the high contrast-to-noise ratio, 3D CISS can be employed in a wide range of scenarios, ranging from the traditional study of cranial nerves, the ventricular system, the subarachnoid cisterns and related pathology to more recently discussed applications, such as the fundamental role it can assume in the setting of acute ischemic stroke, vascular malformations, infections and several brain tumors. In this review, after briefly summarizing its fundamental physical principles, we examine in detail the various applications of 3D CISS in brain imaging, providing numerous representative cases, so as to help radiologists improve its use in imaging protocols in daily clinical practice.

Elucidating the Role of Baseline Leukoaraiosis on Forecasting Clinical Outcome of Acute Ischemic Stroke Patients Undergoing Reperfusion Therapy.

Stroke stands as a major cause of death and disability with increasing prevalence. The absence of clinical improvement after either intravenous thrombolysis (IVT) or mechanical thrombectomy (MT) represents a frequent concern in the setting of acute ischemic stroke (AIS). In an attempt to optimize overall stroke management, it is clinically valuable to provide important insight into functional outcomes after reperfusion therapy among patients presenting with AIS. The aim of the present review is to explore the predictive value of leukoaraiosis (LA) in terms of clinical response to revascularization poststroke. A literature research of two databases (MEDLINE and Scopus) was conducted in order to trace all relevant studies published between 1 January 2012 and 1 November 2022 that focused on the potential utility of LA severity regarding reperfusion status and clinical outcome after revascularization. A total of 37 articles have been traced and included in this review. LA burden assessment is indicative of functional outcome post-intervention and may be associated with hemorrhagic events' incidence among stroke individuals. Nevertheless, LA may not solely guide decision-making about treatment strategy poststroke. Overall, the evaluation of LA upon admission seems to have interesting prognostic potential and may substantially enhance individualized stroke care.

Endovascular Treatment of Tandem Atherosclerotic Cervical Internal Carotid Artery Occlusion in the Setting of Acute Ischemic Stroke.

Among tandem occlusions, atherosclerotic cervical internal carotid artery occlusion (ACICAO) can be technically challenging and associated with its unique complications. We evaluated our experience with endovascular treatment (EVT) of ACICAO in the setting of acute ischemic stroke. In total, 154 consecutive patients who underwent EVT for acute anterior circulation stroke at our institute were retrospectively reviewed. Patients with tandem ACICAO were analyzed in this study. Procedures, recanalization rates, complications, and prognoses were evaluated. Ten patients (6%) of all 154 patients had ACICAO. In nine (90%) of the 10 patients, cervical lesions were successfully crossed and intervened upon. Four patients underwent stenting and five underwent angioplasty alone, followed by intracranial procedure. Eight patients (80%) achieved successful recanalization following mechanical thrombectomy for intracranial occlusion. However, one patient had massive subarachnoid hemorrhage during the procedure and another patient developed massive intracranial hemorrhage after EVT, both after stenting. Four of the five patients who initially underwent angioplasty alone subsequently underwent staged endarterectomy or stenting for residual stenosis on or after the next day. The single patient in whom the cervical lesion could not be crossed and another with reocclusion after EVT underwent a rescue bypass procedure due to persistent ischemic symptoms. After 90days, four patients (40%) were functionally independent (modified Rankin scale score 0-2). Our experience suggests that EVT for ACICAO is technically feasible; however, it involves the potential risk of several significant complications. To avoid serious hemorrhagic complications, cervical lesions may be better treated with angioplasty alone first.

Radiomics-based infarct features on CT predict hemorrhagic transformation in patients with acute ischemic stroke.

ObjectiveTo develop and validate a model based on the radiomics features of the infarct areas on non-contrast-enhanced CT to predict hemorrhagic transformation (HT) in acute ischemic stroke.Materials and methodsA total of 118 patients diagnosed with acute ischemic stroke in two centers from January 2019 to February 2022 were included. The radiomics features of infarcted areas on non-contrast-enhanced CT were extracted using 3D-Slicer. A univariate analysis and the least absolute shrinkage and selection operator (LASSO) were used to select features, and the radiomics score (Rad-score) was then constructed. The predictive model of HT was constructed by analyzing the Rad-score and clinical and imaging features in the training cohort, and it was verified in the validation cohort. The model was evaluated with the receiver operating characteristic curve, calibration curve and decision curve, and the prediction performance of the model in different scenarios was further discussed hierarchically.ResultsOf the 118 patients, 52 developed HT, including 21 cases of hemorrhagic infarct (HI) and 31 cases of parenchymal hematoma (PH). The Rad-score was constructed from five radiomics features and was the only independent predictor for HT. The predictive model was constructed from the Rad-score. The area under the curve (AUCs) of the model for predicting HT in the training and validation cohorts were 0.845 and 0.750, respectively. Calibration curve and decision curve analyses showed that the model performed well. Further analysis found that the model predicted HT for different infarct sizes or treatment methods in the training and validation cohorts with 78.3 and 71.4% accuracy, respectively. For all samples, the model predicted an AUC of 0.754 for HT in patients within 4.5 h since stroke onset, and predicted an AUC of 0.648 for PH.ConclusionThis model, which was based on CT radiomics features, could help to predict HT in the setting of acute ischemic stroke for any infarct size and provide guiding suggestions for clinical treatment and prognosis evaluation.

Composition and Organization of Acute Ischemic Stroke Thrombus: A Wealth of Information for Future Thrombolytic Strategies.

During the last decade, significant progress has been made in understanding thrombus composition and organization in the setting of acute ischemic stroke (AIS). In particular, thrombus organization is now described as highly heterogeneous but with 2 preserved characteristics: the presence of (1) two distinct main types of areas in the core—red blood cell (RBC)-rich and platelet-rich areas in variable proportions in each thrombus—and (2) an external shell surrounding the core composed exclusively of platelet-rich areas. In contrast to RBC-rich areas, platelet-rich areas are highly complex and are mainly responsible for the thrombolysis resistance of these thrombi for the following reasons: the presence of platelet-derived fibrinolysis inhibitors in large amounts, modifications of the fibrin network structure resistant to the tissue plasminogen activator (tPA)-induced fibrinolysis, and the presence of non-fibrin extracellular components, such as von Willebrand factor (vWF) multimers and neutrophil extracellular traps. From these studies, new therapeutic avenues are in development to increase the fibrinolytic efficacy of intravenous (IV) tPA-based therapy or to target non-fibrin thrombus components, such as platelet aggregates, vWF multimers, or the extracellular DNA network.

A Model for Encephalomyosynangiosis Treatment after Middle Cerebral Artery Occlusion-Induced Stroke in Mice.

There is no effective treatment available for most patients suffering with ischemic stroke, making development of novel therapeutics imperative. The brain's ability to self-heal after ischemic stroke is limited by inadequate blood supply in the impacted area. Encephalomyosynangiosis (EMS) is a neurosurgical procedure that achieves angiogenesis in patients with moyamoya disease. It involves craniotomy with placement of a vascular temporalis muscle graft on the ischemic brain surface. EMS has never been studied in the setting of acute ischemic stroke in mice. The hypothesis driving this study is that EMS enhances cerebral angiogenesis at the cortical surface surrounding the muscle graft. The protocol shown here describes the procedure and provides initial data supporting the feasibility and efficacy of the EMS approach. In this protocol, after 60 min of transient middle cerebral artery occlusion (MCAo), mice were randomized to either MCAo or MCAo + EMS treatment. The EMS was performed 3-4 h after occlusion. The mice were sacrificed 7 or 21 days after MCAo or MCAo + EMS treatment. Temporalis graft viability was measured using nicotinamide adenine dinucleotide reduced-tetrazolium reductase assay. A mouse angiogenesis array quantified angiogenic and neuromodulating protein expression. Immunohistochemistry was used to visualize graft bonding with brain cortex and change in vessel density. The preliminary data here suggest that grafted muscle remained viable 21 days after EMS. Immunostaining showed successful graft implantation and increase in vessel density near the muscle graft, indicating increased angiogenesis. Data show that EMS increases fibroblast growth factor (FGF) and decreases osteopontin levels after stroke. Additionally, EMS after stroke did not increase mortality suggesting that protocol is safe and reliable. This novel procedure is effective and well-tolerated and has the potential to provide information of novel interventions for enhanced angiogenesis after acute ischemic stroke.

Collateral Blood Flow and Ischemic Core Growth.

Treatment of a large vessel occlusion in the acute ischemic stroke setting focuses on vessel recanalization, and endovascular thrombectomy results in favorable outcomes in appropriate candidates. Expeditious treatment is imperative, but patients often present to institutions that do not have neurointerventional surgeons and need to be transferred to a comprehensive stroke center. These treatment delays are common, and it is important to identify factors that mitigate the progression of the ischemic core in order to maximize the preservation of salvageable brain tissue. Collateral blood flow is the strongest factor known to influence ischemic core growth, which includes the input arterial vessels, tissue-level vessels, and venous outflow. Collateral blood flow at these different levels may be imaged by specific imaging techniques that may also predict ischemic core growth during treatment delays and help identify patients who would benefit from transfer and endovascular therapy, as well as identify those patients in whom transfer may be futile. Here we review collateral blood flow and its relationship to ischemic core growth in stroke patients.