A dynamic nomogram for predict individual risk of malignant brain edema after endovascular thrombectomy in acute ischemic stroke.

The aim of this study was to develop a dynamic nomogram combining clinical and imaging data to predict malignant brain edema (MBE) after endovascular thrombectomy (EVT) in patients with large vessel occlusion stroke (LVOS). We analyzed the data of LVOS patients receiving EVT at our center from October 2018 to February 2023, and divided a 7:3 ratio into the training cohort and internal validation cohort, and we also prospectively collected patients from another stroke center for external validation. MBE was defined as a midline shift or pineal gland shift > 5 mm, as determined by computed tomography (CT) scans obtained within 7 days after EVT. A nomogram was constructed using logistic regression analysis, and its receiver operating characteristic curve (ROC) and calibration were assessed in three cohorts. A total of 432 patients were enrolled in this study, with 247 in the training cohort, 100 in the internal validation cohort, and 85 in the external validation cohort. MBE occurred in 24% (59) in the training cohort, 16% (16) in the internal validation cohort and 14% (12) in the external validation cohort. After adjusting for various confounding factors, we constructed a nomogram including the clot burden score (CBS), baseline neutrophil count, core infarct volume on CTP before EVT, collateral index, and the number of retrieval attempts. The AUCs of the training cohorts were 0.891 (95% CI 0.840-0.942), the Hosmer-Lemeshow test showed good calibration of the nomogram (P = 0.879). And our nomogram performed well in both internal and external validation data. Our nomogram demonstrates promising potential in identifying patients at elevated risk of MBE following EVT for LVOS.

Data Extraction from Free-Text Reports on Mechanical Thrombectomy in Acute Ischemic Stroke Using ChatGPT: A Retrospective Analysis.

Background Procedural details of mechanical thrombectomy in patients with ischemic stroke are important predictors of clinical outcome and are collected for prospective studies or national stroke registries. To date, these data are collected manually by human readers, a labor-intensive task that is prone to errors. Purpose To evaluate the use of the large language models (LLMs) GPT-4 and GPT-3.5 to extract data from neuroradiology reports on mechanical thrombectomy in patients with ischemic stroke. Materials and Methods This retrospective study included consecutive reports from patients with ischemic stroke who underwent mechanical thrombectomy between November 2022 and September 2023 at institution 1 and between September 2016 and December 2019 at institution 2. A set of 20 reports was used to optimize the prompt, and the ability of the LLMs to extract procedural data from the reports was compared using the McNemar test. Data manually extracted by an interventional neuroradiologist served as the reference standard. Results A total of 100 internal reports from 100 patients (mean age, 74.7 years ± 13.2 [SD]; 53 female) and 30 external reports from 30 patients (mean age, 72.7 years ± 13.5; 18 male) were included. All reports were successfully processed by GPT-4 and GPT-3.5. Of 2800 data entries, 2631 (94.0% [95% CI: 93.0, 94.8]; range per category, 61%-100%) data points were correctly extracted by GPT-4 without the need for further postprocessing. With 1788 of 2800 correct data entries, GPT-3.5 produced fewer correct data entries than did GPT-4 (63.9% [95% CI: 62.0, 65.6]; range per category, 14%-99%; P < .001). For the external reports, GPT-4 extracted 760 of 840 (90.5% [95% CI: 88.3, 92.4]) correct data entries, while GPT-3.5 extracted 539 of 840 (64.2% [95% CI: 60.8, 67.4]; P < .001). Conclusion Compared with GPT-3.5, GPT-4 more frequently extracted correct procedural data from free-text reports on mechanical thrombectomy performed in patients with ischemic stroke. © RSNA, 2024 Supplemental material is available for this article.

Application of radiomics in ischemic stroke.

In recent years, radiomics has emerged as a novel research methodology that plays a crucial role in the diagnosis and treatment of ischemic stroke. By integrating multimodal medical imaging techniques such as computed tomography and magnetic resonance imaging, radiomics offers in-depth insights into aspects such as the extent of brain tissue damage and hemodynamics. These data help physicians to accurately assess patient condition, select optimal treatment strategies, and predict recovery trajectories and long-term prognoses, thereby enhancing treatment efficacy and reducing the risk of complications. With the anticipated further advancements in radiomic technology, this methodology has great potential for expanded applications in the early detection, treatment, and prognosis of ischemic stroke. The present narrative review explores the burgeoning field of radiomics and its transformative impact on ischemic stroke.

MRI in the Evaluation of Cryptogenic Stroke and Embolic Stroke of Undetermined Source.

Cryptogenic stroke refers to a stroke of undetermined etiology. It accounts for approximately one-fifth of ischemic strokes and has a higher prevalence in younger patients. Embolic stroke of undetermined source (ESUS) refers to a subgroup of patients with nonlacunar cryptogenic strokes in whom embolism is the suspected stroke mechanism. Under the classifications of cryptogenic stroke or ESUS, there is wide heterogeneity in possible stroke mechanisms. In the absence of a confirmed stroke etiology, there is no established treatment for secondary prevention of stroke in patients experiencing cryptogenic stroke or ESUS, despite several clinical trials, leaving physicians with a clinical dilemma. Both conventional and advanced MRI techniques are available in clinical practice to identify differentiating features and stroke patterns and to determine or infer the underlying etiologic cause, such as atherosclerotic plaques and cardiogenic or paradoxical embolism due to occult pelvic venous thrombi. The aim of this review is to highlight the diagnostic utility of various MRI techniques in patients with cryptogenic stroke or ESUS. Future trends in technological advancement for promoting the adoption of MRI in such a special clinical application are also discussed.

[You only ECHO Twice].

INTRODUCTION: Ischaemic stroke results from a sudden interruption of cerebral blood flow, often caused by thrombosis, embolism or hypoperfusion. Rarely, cardiac tumours are the cause of an embolic event. We report on an 80-year-old woman with a cerebral stroke. Successful thrombectomy revealed a histopathologically confirmed papillary fibroelastoma as the embolic source. Although it was not detectable on initial echocardiography, the tumour was discovered by transesophageal echocardiography. This case emphasises the importance of considering primary cardiac tumours as potential sources of emboli in ischaemic stroke. Keywords.

Angiographic demonstration of a cutoff sign as an unfavorable prognostic indicator for patients with acute ischemic stroke undergoing mechanical thrombectomy.

OBJECTIVES: The aim was to investigate whether the angiographic demonstration of a cutoff sign on the initial angiogram could predict recanalization and prognosis in acute ischemic stroke patients treated by endovascular thrombectomy. METHODS: The angiographic and clinical data of patients who underwent endovascular treatment from October 2018 to April 2023 were retrospectively reviewed. The pretreatment angiographic appearance of the thrombus's proximal part was assessed and classified as either the cutoff sign (+) or (-). Patients' baseline characteristics and angiographic and clinical outcomes between the two groups were analyzed using propensity score matching. Then, the two commonly used techniques, stent retrieval and contact aspiration, were compared in terms of successful reperfusion and clinical outcome in patients with the cutoff sign. RESULTS: The cutoff sign was observed in 77 (36.2%) of 213 patients. Patients with the cutoff sign were younger and were less likely to have involvement of the anterior circulation. Compared with the cutoff sign (-) group, the cutoff sign (+) group had a significantly longer procedure time (103 versus 80 min, P =0.002) and a lower percentage of 3-month good functional outcomes (18.2% versus 36%, P =0.006). After propensity score matching, the procedure time (100 versus 75 min, P =0.002) and the 3-month good outcome (19.2% versus 41.4%, P =0.004) remained significantly different. No significant differences were observed in the radiological (OR 0.758, 95% CI 0.157 to 3.658; P =0.730) and clinical (OR 0.747, 95% CI 0.147 to 3.787; P =0.725) outcomes between the two techniques. CONCLUSIONS: The cutoff sign might be an unfavorable prognostic indicator in patients undergoing mechanical thrombectomy, and the efficacy of mechanical thrombectomy techniques does not differ in patients positive for the cutoff sign.

Comprehensive Assessment of Ischemic Stroke in Nonhuman Primates: Neuroimaging, Behavioral, and Serum Proteomic Analysis.

Ischemic strokes, prevalence and impactful, underscore the necessity of advanced research models closely resembling human physiology. Our study utilizes nonhuman primates (NHPs) to provide a detailed exploration of ischemic stroke, integrating neuroimaging data, behavioral outcomes, and serum proteomics to elucidate the complex interplay of factors involved in stroke pathophysiology. We observed a consistent pattern in infarct volume, peaking at 1-month postmiddle cerebral artery occlusion (MCAO) and then stabilized. This pattern was strongly correlated to notable changes in motor function and working memory performance. Using diffusion tensor imaging (DTI), we detected significant alterations in fractional anisotropy (FA) and mean diffusivity (MD) values, signaling microstructural changes in the brain. These alterations closely correlated with the neurological and cognitive deficits that we observed, highlighting the sensitivity of DTI metrics in stroke assessment. Behaviorally, the monkeys exhibited a reliance on their unaffected limb for compensatory movements, a common response to stroke impairment. This adaptation, along with consistent DTI findings, suggests a significant impact of stroke on motor function and spatial perception. Proteomic analysis through MS/MS functional enrichment identified two distinct groups of proteins with significant changes post-MCAO. Notably, MMP9, THBS1, MB, PFN1, and YWHAZ were identified as potential biomarkers and therapeutic targets for ischemic stroke. Our results underscore the complex nature of stroke and advocate for an integrated approach, combining neuroimaging, behavioral studies, and proteomics, for advancing our understanding and treatment of this condition.

Annotation-free prediction of treatment-specific tissue outcome from 4D CT perfusion imaging in acute ischemic stroke.

Acute ischemic stroke is a critical health condition that requires timely intervention. Following admission, clinicians typically use perfusion imaging to facilitate treatment decision-making. While deep learning models leveraging perfusion data have demonstrated the ability to predict post-treatment tissue infarction for individual patients, predictions are often represented as binary or probabilistic masks that are not straightforward to interpret or easy to obtain. Moreover, these models typically rely on large amounts of subjectively segmented data and non-standard perfusion analysis techniques. To address these challenges, we propose a novel deep learning approach that directly predicts follow-up computed tomography images from full spatio-temporal 4D perfusion scans through a temporal compression. The results show that this method leads to realistic follow-up image predictions containing the infarcted tissue outcomes. The proposed compression method achieves comparable prediction results to using perfusion maps as inputs but without the need for perfusion analysis or arterial input function selection. Additionally, separate models trained on 45 patients treated with thrombolysis and 102 treated with thrombectomy showed that each model correctly captured the different patient-specific treatment effects as shown by image difference maps. The findings of this work clearly highlight the potential of our method to provide interpretable stroke treatment decision support without requiring manual annotations.

[A case of suspected vertebral artery stump syndrome assessed by CT angiography].

A 55-year-old man developed ischemic stroke in the bilateral cerebellar hemispheres and bilateral occipital lobes. He was admitted to our hospital 17 months later with recurrent ischemic stroke in the posterior circulation. The left vertebral artery (VA) was occluded on brain magnetic resonance angiography but was visualized with a delay on continuous three-phase CT angiography (CTA). Conventional angiography confirmed a to-and-fro blood flow pattern at the distal end of the left VA, therefore the patient was diagnosed with VA stump syndrome (VASS). VASS is a recurrent posterior circulation ischemic stroke caused by thrombi in an occluded unilateral VA. VASS should be suspected in patients with unilateral VA occlusion and repeated posterior-circulation ischemic stroke. The diagnostic criteria for VASS include confirmation of VA occlusion and the presence of an antegrade flow component at the distal end. In this case, the presence of collateral circulation in the VA was suspected based on CTA findings, leading to the diagnosis of VASS. It was thus suggested that devising the imaging method of CTA may help diagnose VASS.

The value of Lp(a) and TG/HDLC in peripheral blood to assess the stability of carotid plaque in patients with ischemic stroke.

OBJECTIVE: The objective of this study was to investigate the relationship between lipoprotein (a) (Lp(a)), triglyceride/high-density lipoprotein cholesterol (TG/HDL-C), and the stability of carotid atherosclerotic plaque in patients with acute ischemic stroke. METHODS: A total of 142 patients with acute ischemic stroke were selected and divided into group A (59 cases of stable plaque formation) and group B (83 cases of unstable plaque formation) according to the characteristics of carotid artery plaque formation detected by carotid color Doppler ultrasound. The serum Lp(a), lipid metabolism indexes, peripheral blood routine indexes, and related serum inflammatory factors indexes were compared between the two groups. Receiver operating characteristic curve and multivariate logistic regression model were used to analyze the relationship between each index and the formation of carotid unstable plaque. RESULTS: There were no significant differences in serum total cholesterol (TC), HDL-C, and low-density lipoprotein cholesterol (LDL-C) between groups A and B (p > .05). The values of Lp(a), TG, and TG/HDL-C in group B were higher than those in group A, and the differences were statistically significant (p < .05). There were no significant differences in serum TC, HDL-C, and LDL-C between groups A and B (p > .05). The values of Lp(a), TG, and TG/HDL-C in group B were higher than those in group A, and the differences were statistically significant (p < .05). The values of HBA1C, Lp-PLA2, CRP, CysC, Hcy, TNF-α, neutrophils, and NLR in group B were higher than those in group A, and the differences were statistically significant (p < .05). There was no significant difference in FPG, systolic blood pressure, diastolic blood pressure, Hb, white blood cells, platelets, and lymphocytes between groups A and B (p > .05). The results of logistic regression model showed that the increase of Lp(a), TG/HDL-C, HBA1C, Lp-PLA2, CRP, CysC, Hcy, and NLR could increase the risk of carotid artery unstable plaque in patients with ischemic stroke (p < .05). CONCLUSION: Lp(a) and TG/HDL-C have certain value in evaluating the stability of carotid atherosclerotic plaque in patients with acute ischemic stroke, and the increased levels of LP (a) and TG/HDL-C will significantly increase the risk of carotid unstable plaque in patients.

A One-Stone-Two-Birds Strategy of Targeting Microbubbles with "Dual" Anti-Inflammatory and Blood-Brain Barrier "Switch" Function for Ischemic Stroke Treatment.

Inflammation is considered to be the main target of the development of new stroke therapies. There are three key issues in the treatment of stroke inflammation: the first one is how to overcome the blood-brain barrier (BBB) to achieve drug delivery, the second one is how to select drugs to treat stroke inflammation, and the third one is how to achieve targeted drug delivery. In this study, we constructed hydrocortisone-phosphatidylserine microbubbles and combined them with ultrasound (US)-targeted microbubble destruction technology to successfully open the BBB to achieve targeted drug delivery. Phosphatidylserine on the microbubbles was used for its "eat me" effect to increase the targeting of the microvesicles. In addition, we found that hydrocortisone can accelerate the closure of the BBB, achieving efficient drug delivery while reducing the entry of peripheral toxins into the brain. In the treatment of stroke inflammation, it was found that hydrocortisone itself has anti-inflammatory effects and can also change the polarization of microglia from the harmful pro-inflammatory M1 phenotype to the beneficial anti-inflammatory M2 phenotype, thus achieving dual anti-inflammatory effects and enhancing the anti-inflammatory effects in ischemic areas after stroke, well reducing the cerebellar infarction volume by inhibiting the inflammatory response after cerebral ischemia. A confocal microendoscope was used to directly observe the polarization of microglial cells in living animal models for dynamic microscopic visualization detection showing the advantage of being closer to clinical work. Taken together, this study constructed a multifunctional targeted US contrast agent with the function of "one-stone-two-birds", which can not only "on-off" the BBB but also have "two" anti-inflammatory functions, providing a new strategy of integrated anti-inflammatory targeted delivery and imaging monitoring for ischemic stroke treatment.

Endovascular Thrombectomy for Large Ischemic Stroke Across Ischemic Injury and Penumbra Profiles.

Importance: Whether endovascular thrombectomy (EVT) efficacy for patients with acute ischemic stroke and large cores varies depending on the extent of ischemic injury is uncertain. Objective: To describe the relationship between imaging estimates of irreversibly injured brain (core) and at-risk regions (mismatch) and clinical outcomes and EVT treatment effect. Design, Setting, and Participants: An exploratory analysis of the SELECT2 trial, which randomized 352 adults (18-85 years) with acute ischemic stroke due to occlusion of the internal carotid or middle cerebral artery (M1 segment) and large ischemic core to EVT vs medical management (MM), across 31 global centers between October 2019 and September 2022. Intervention: EVT vs MM. Main Outcomes and Measures: Primary outcome was functional outcome-90-day mRS score (0, no symptoms, to 6, death) assessed by adjusted generalized OR (aGenOR; values >1 represent more favorable outcomes). Benefit of EVT vs MM was assessed across levels of ischemic injury defined by noncontrast CT using ASPECTS score and by the volume of brain with severely reduced blood flow on CT perfusion or restricted diffusion on MRI. Results: Among 352 patients randomized, 336 were analyzed (median age, 67 years; 139 [41.4%] female); of these, 168 (50%) were randomized to EVT, and 2 additional crossover MM patients received EVT. In an ordinal analysis of mRS at 90 days, EVT improved functional outcomes compared with MM within ASPECTS categories of 3 (aGenOR, 1.71 [95% CI, 1.04-2.81]), 4 (aGenOR, 2.01 [95% CI, 1.19-3.40]), and 5 (aGenOR, 1.85 [95% CI, 1.22-2.79]). Across strata for CT perfusion/MRI ischemic core volumes, aGenOR for EVT vs MM was 1.63 (95% CI, 1.23-2.16) for volumes ≥70 mL, 1.41 (95% CI, 0.99-2.02) for ≥100 mL, and 1.47 (95% CI, 0.84-2.56) for ≥150 mL. In the EVT group, outcomes worsened as ASPECTS decreased (aGenOR, 0.91 [95% CI, 0.82-1.00] per 1-point decrease) and as CT perfusion/MRI ischemic core volume increased (aGenOR, 0.92 [95% CI, 0.89-0.95] per 10-mL increase). No heterogeneity of EVT treatment effect was observed with or without mismatch, although few patients without mismatch were enrolled. Conclusion and Relevance: In this exploratory analysis of a randomized clinical trial of patients with extensive ischemic stroke, EVT improved clinical outcomes across a wide spectrum of infarct volumes, although enrollment of patients with minimal penumbra volume was low. In EVT-treated patients, clinical outcomes worsened as presenting ischemic injury estimates increased. Trial Registration: ClinicalTrials.gov Identifier: NCT03876457.

Arterial transit artifact as a short-term prognostic indicator in acute ischemic stroke.

BACKGROUND: Arterial transit artifact (ATA) observed on arterial spin labeling (ASL) was recently suggested to be associated with improved functional outcomes following acute ischemic stroke (AIS). AIS is a heterogeneous disease with diverse pathogenic mechanisms depending on the stroke subtype. This study aimed to investigate the association between ATA and 3-month functional outcomes in AIS patients according to etiology subtypes. METHODS: Consecutive patients with AIS were included. All patients underwent ASL MRI with postlabeling delay (PLD) of 1.5 and 2.5 s. ATA was assessed from the ASL images of both PLDs. Stroke etiologic subtypes were determined according to the modified TOAST (Trial of ORG 10172 in Acute Stroke Treatment) classification. Short-term functional outcomes were evaluated using the 3-month modified Rankin scale (mRS). Log-binomial regression was applied to analyze the association between ATA and functional outcomes at 3 months after stroke. RESULTS: Ninety-eight AIS patients (62.73 ± 13.05 years; 68 men) were finally included. ATA was detected in forty-six patients and most frequently seen in the large-artery atherosclerosis (LAA) subtype (35/46). The ATA group exhibited a lower percentage of patients with mRS > 2 compared to the group without ATA (36.5% vs. 19.6%; P < 0.001). ATA was independently associated with better 3-month clinical outcomes (adjusted risk ratio, 0.35[95% CI, 0.16-0.74]) in the multivariate log-binomial regression model. After stratification by TOAST subtypes, a significant association was found between ATA and better outcomes in the LAA subtype (adjusted risk ratio, 0.20[ 95% CI, 0.05-0.72]) but not in cardioembolism and small artery occlusion (SVO) subtype. CONCLUSION: ATA is associated with better outcomes at 3 months in patients with AIS, especially in the LAA subtype, but this association attenuated in the cardioembolism and SVO subtypes.

Carotid web as a cause of recurrent ischaemic strokes.

This case report presents a 37-year-old woman with two episodes of temporary left-sided hemiparesis. Brain scans (CT and MRI) showed multiple ischaemic lesions in the right hemisphere. During the next two months, the patient had four additional ischaemic events in the right hemisphere, also localised within the anterior circulation. An extensive diagnostic workup was done, and the patient was ultimately diagnosed with carotid web (CW) in the right internal carotid artery. Treatment of CW should be considered in cryptogenic, recurrent, unihemispheric stroke in younger patients to prevent recurrent stroke.

First pass effect in patients undergoing endovascular treatment for posterior circulation acute ischemic stroke.

OBJECTIVE: This study aims to investigate the impact of first pass effect (FPE) on outcomes in the posterior circulation acute ischemic stroke (PC-AIS) and the independent predictors of FPE. METHODS: This was a multicenter, retrospective study. PC-AIS patients who underwent endovascular treatment were reviewed. The cohort achieving complete or nearly complete reperfusion (defined as expanded treatment in cerebralischemia [eTICI] ≥ 2c) was categorized into the FPE and multiple pass effect (MPE) groups. FPE was defined as achieving eTICI ≥ 2c with a single pass and without the use of rescue therapy. Modified FPE (mFPE) was defined as meeting the criteria for FPE but with eTICI ≥ 2b. The association of FPE with 90-day clinical outcomes and predictors for FPE were both investigated. RESULTS: The study included a total of 328 patients, with 69 patients (21 %) in the FPE group. For primary outcome, FPE had a significant higher favorable outcome (mRS ≤ 3) rate than MPE (65.2 % vs. 44.8 %, p = 0.003). Similar outcomes were observed in the mFPE. Furthermore, FPE was significantly associated with favorable outcome (adjusted OR 2.23, 95 % CI 1.06-4.73, p = 0.036). Positive predictors for FPE included occlusion in the distal basilar artery, the first-line aspiration or combination, and cardioembolic etiology. Negative predictors for FPE included hypertension and general anesthesia. CONCLUSION: For PC-AIS patients due to large or medium vessel occlusion, FPE is associated with favorable clinical outcomes. The first-line techniques of aspiration or combination, as well as avoiding general anesthesia, contribute to a better realization of FPE.

Tenecteplase for Stroke at 4.5 to 24 Hours with Perfusion-Imaging Selection.

BACKGROUND: Thrombolytic agents, including tenecteplase, are generally used within 4.5 hours after the onset of stroke symptoms. Information on whether tenecteplase confers benefit beyond 4.5 hours is limited. METHODS: We conducted a multicenter, double-blind, randomized, placebo-controlled trial involving patients with ischemic stroke to compare tenecteplase (0.25 mg per kilogram of body weight, up to 25 mg) with placebo administered 4.5 to 24 hours after the time that the patient was last known to be well. Patients had to have evidence of occlusion of the middle cerebral artery or internal carotid artery and salvageable tissue as determined on perfusion imaging. The primary outcome was the ordinal score on the modified Rankin scale (range, 0 to 6, with higher scores indicating greater disability and a score of 6 indicating death) at day 90. Safety outcomes included death and symptomatic intracranial hemorrhage. RESULTS: The trial enrolled 458 patients, 77.3% of whom subsequently underwent thrombectomy; 228 patients were assigned to receive tenecteplase, and 230 to receive placebo. The median time between the time the patient was last known to be well and randomization was approximately 12 hours in the tenecteplase group and approximately 13 hours in the placebo group. The median score on the modified Rankin scale at 90 days was 3 in each group. The adjusted common odds ratio for the distribution of scores on the modified Rankin scale at 90 days for tenecteplase as compared with placebo was 1.13 (95% confidence interval, 0.82 to 1.57; P = 0.45). In the safety population, mortality at 90 days was 19.7% in the tenecteplase group and 18.2% in the placebo group, and the incidence of symptomatic intracranial hemorrhage was 3.2% and 2.3%, respectively. CONCLUSIONS: Tenecteplase therapy that was initiated 4.5 to 24 hours after stroke onset in patients with occlusions of the middle cerebral artery or internal carotid artery, most of whom had undergone endovascular thrombectomy, did not result in better clinical outcomes than those with placebo. The incidence of symptomatic intracerebral hemorrhage was similar in the two groups. (Funded by Genentech; TIMELESS ClinicalTrials.gov number, NCT03785678.).

Neuron-specific enolase at admission as a predictor for stroke volume, severity and outcome in ischemic stroke patients: a prognostic biomarker review.

An ideal blood biomarker for stroke should provide reliable results, enable fast diagnosis, and be readily accessible for practical use. Neuron-specific enolase (NSE), an enzyme released after neuronal damage, has been studied as a marker for brain injury, including cerebral infarction. However, different methodologies and limited sample sizes have restricted the applicability of any potential findings. This work aims to determine whether NSE levels at Emergency Department (ED) admission correlate with stroke severity, infarcted brain volume, functional outcome, and/or death rates. A systematic literature review was performed using PubMed, Embase, and Scopus databases. Each reviewer independently assessed all published studies identified as potentially relevant. All relevant original observational studies (cohort, case-control, and cross-sectional studies) were included. Eleven studies (1398 patients) met the inclusion criteria. Among these, six studies reported a significant correlation between NSE levels and stroke severity, while only one found no association. Four studies indicated a positive relationship between infarcted brain volume assessed by imaging and NSE levels, in contrast to the findings of only one study. Four studies identified an association related to functional outcome and death rates, while three others did not reach statistical significance in their findings. These data highlight that NSE levels at ED admissions proved to be a promising tool for predicting the outcome of ischemic stroke patients in most studies. However, they presented high discrepancies and low robustness. Therefore, further research is necessary to establish and define the role of NSE in clinical practice.

Ultrafast Brain MRI with Deep Learning Reconstruction for Suspected Acute Ischemic Stroke.

Background Deep learning (DL)-accelerated MRI can substantially reduce examination times. However, studies prospectively evaluating the diagnostic performance of DL-accelerated MRI reconstructions in acute suspected stroke are lacking. Purpose To investigate the interchangeability of DL-accelerated MRI with conventional MRI in patients with suspected acute ischemic stroke at 1.5 T. Materials and Methods In this prospective study, 211 participants with suspected acute stroke underwent clinically indicated MRI at 1.5 T between June 2022 and March 2023. For each participant, conventional MRI (including T1-weighted, T2-weighted, T2*-weighted, T2 fluid-attenuated inversion-recovery, and diffusion-weighted imaging; 14 minutes 18 seconds) and DL-accelerated MRI (same sequences; 3 minutes 4 seconds) were performed. The primary end point was the interchangeability between conventional and DL-accelerated MRI for acute ischemic infarction detection. Secondary end points were interchangeability regarding the affected vascular territory and clinically relevant secondary findings (eg, microbleeds, neoplasm). Three readers evaluated the overall occurrence of acute ischemic stroke, affected vascular territory, clinically relevant secondary findings, overall image quality, and diagnostic confidence. For acute ischemic lesions, size and signal intensities were assessed. The margin for interchangeability was chosen as 5%. For interrater agreement analysis and interrater reliability analysis, multirater Fleiss κ and the intraclass correlation coefficient, respectively, was determined. Results The study sample consisted of 211 participants (mean age, 65 years ± 16 [SD]); 123 male and 88 female). Acute ischemic stroke was confirmed in 79 participants. Interchangeability was demonstrated for all primary and secondary end points. No individual equivalence indexes (IEIs) exceeded the interchangeability margin of 5% (IEI, -0.002 [90% CI: -0.007, 0.004]). Almost perfect interrater agreement was observed (P > .91). DL-accelerated MRI provided higher overall image quality (P < .001) and diagnostic confidence (P < .001). The signal properties of acute ischemic infarctions were similar in both techniques and demonstrated good to excellent interrater reliability (intraclass correlation coefficient, ≥0.8). Conclusion Despite being four times faster, DL-accelerated brain MRI was interchangeable with conventional MRI for acute ischemic lesion detection. © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Haller in this issue.

Endovascular thrombectomy plus medical care versus medical care alone for large ischaemic stroke: 1-year outcomes of the SELECT2 trial.

BACKGROUND: Multiple randomised trials have shown efficacy and safety of endovascular thrombectomy in patients with large ischaemic stroke. The aim of this study was to evaluate long-term (ie, at 1 year) evidence of benefit of thrombectomy for these patients. METHODS: SELECT2 was a phase 3, open-label, international, randomised controlled trial with blinded endpoint assessment, conducted at 31 hospitals in the USA, Canada, Spain, Switzerland, Australia, and New Zealand. Patients aged 18-85 years with ischaemic stroke due to proximal occlusion of the internal carotid artery or of the first segment of the middle cerebral artery, showing large ischaemic core on non-contrast CT (Alberta Stroke Program Early Computed Tomographic Score of 3-5 [range 0-10, with lower values indicating larger infarctions]) or measuring 50 mL or more on CT perfusion and MRI, were randomly assigned, within 24 h of ischaemic stroke onset, to thrombectomy plus medical care or to medical care alone. The primary outcome for this analysis was the ordinal modified Rankin Scale (range 0-6, with higher scores indicating greater disability) at 1-year follow-up in an intention-to-treat population. The trial is registered at ClinicalTrials.gov (NCT03876457) and is completed. FINDINGS: The trial was terminated early for efficacy at the 90-day follow-up after 352 patients had been randomly assigned (178 to thrombectomy and 174 to medical care only) between Oct 11, 2019, and Sept 9, 2022. Thrombectomy significantly improved the 1-year modified Rankin Scale score distribution versus medical care alone (Wilcoxon-Mann-Whitney probability of superiority 0·59 [95% CI 0·53-0·64]; p=0·0019; generalised odds ratio 1·43 [95% CI 1·14-1·78]). At the 1-year follow-up, 77 (45%) of 170 patients receiving thrombectomy had died, compared with 83 (52%) of 159 patients receiving medical care only (1-year mortality relative risk 0·89 [95% CI 0·71-1·11]). INTERPRETATION: In patients with ischaemic stroke due to a proximal occlusion and large core, thrombectomy plus medical care provided a significant functional outcome benefit compared with medical care alone at 1-year follow-up. FUNDING: Stryker Neurovascular.