Collateral Automation for Triage in Stroke: Evaluating Automated Scoring of Collaterals in Acute Stroke on Computed Tomography ScansComputed tomography angiography (CTA) collateral scoring can identify patients most likely to benefit from mechanical thrombectomy and those more likely to have good outcomes and ranges from 0 (no collaterals) to 3 (complete collaterals). In this study, we used a machine learning approach to categorise the degree of collateral flow in 98 patients who were eligible for mechanical thrombectomy and generate an e-CTA collateral score (CTA-CS) for each patient (e-STROKE SUITE, Brainomix Ltd., Oxford, UK). Three experienced neuroradiologists (NRs) independently estimated the CTA-CS, first without and then with knowledge of the e-CTA output, before finally agreeing on a consensus score. Addition of the e-CTA improved the intraclass correlation coefficient (ICC) between NRs from 0.58 (0.46-0.67) to 0.77 (0.66-0.85, p = 0.003). Automated e-CTA, without NR input, agreed with the consensus score in 90% of scans with the remaining 10% within 1 point of the consensus (ICC 0.93, 0.90-0.95). Sensitivity and specificity for identifying favourable collateral flow (collateral score 2-3) were 0.99 (0.93-1.00) and 0.94 (0.70-1.00), respectively. e-CTA correlated with the Alberta Stroke Programme Early CT Score (Spearman correlation 0.46, p < 0.001) highlighting the value of good collateral flow in maintaining tissue viability prior to reperfusion. In conclusion, -e-CTA provides a real-time and fully automated approach to collateral scoring with the potential to improve consistency of image interpretation and to independently quantify collateral scores even without expert rater input.
Perfusion Imaging for Endovascular Thrombectomy in Acute Ischemic Stroke Is Associated With Improved Functional Outcomes in the Early and Late Time WindowsBackground: The impact on clinical outcomes of patient selection using perfusion imaging for endovascular thrombectomy (EVT) in patients with acute ischemic stroke presenting beyond 6 hours from onset remains undetermined in routine clinical practice. Methods: Patients from a national stroke registry that underwent EVT selected with or without perfusion imaging (noncontrast computed tomography/computed tomography angiography) in the early (<6 hours) and late (6–24 hours) time windows, between October 2015 and March 2020, were compared. The primary outcome was the ordinal shift in the modified Rankin Scale score at hospital discharge. Other outcomes included functional independence (modified Rankin Scale score ≤2) and in-hospital mortality, symptomatic intracerebral hemorrhage, successful reperfusion (Thrombolysis in Cerebral Infarction score 2b–3), early neurological deterioration, futile recanalization (modified Rankin Scale score 4–6 despite successful reperfusion) and procedural time metrics. Multivariable analyses were performed, adjusted for age, sex, baseline stroke severity, prestroke disability, intravenous thrombolysis, mode of anesthesia (Model 1) and including EVT technique, balloon guide catheter, and center (Model 2). Results: We included 4249 patients, 3203 in the early window (593 with perfusion versus 2610 without perfusion) and 1046 in the late window (378 with perfusion versus 668 without perfusion). Within the late window, patients with perfusion imaging had a shift towards better functional outcome at discharge compared with those without perfusion imaging (adjusted common odds ratio [OR], 1.45 [95% CI, 1.16–1.83]; P =0.001). There was no significant difference in functional independence (29.3% with perfusion versus 24.8% without; P =0.210) or in the safety outcome measures of symptomatic intracerebral hemorrhage ( P =0.53) and in-hospital mortality (10.6% with perfusion versus 14.3% without; P =0.053). In the early time window, patients with perfusion imaging had significantly improved odds of functional outcome (adjusted common OR, 1.51 [95% CI, 1.28–1.78]; P =0.0001) and functional independence (41.6% versus 33.6%, adjusted OR, 1.31 [95% CI, 1.08–1.59]; P =0.006). Perfusion imaging was associated with lower odds of futile recanalization in both time windows (late: adjusted OR, 0.70 [95% CI, 0.50–0.97]; P =0.034; early: adjusted OR, 0.80 [95% CI, 0.65–0.99]; P =0.047). Conclusions: In this real-world study, acquisition of perfusion imaging for EVT was associated with improvement in functional disability in the early and late time windows compared with nonperfusion neuroimaging. These indirect comparisons should be interpreted with caution while awaiting confirmatory data from prospective randomized trials.
Virtual reality in post-stroke neurorehabilitation – a systematic review and meta-analysisAzka Khan, Anna Podlasek, Fahad Somaa|Topics in Stroke Rehabilitation|2021 Background Stroke is a neurological disorder and one of the leading causes of disability worldwide. The patient may lose the ability to adequately move the extremities, perceive sensations, or ambulate independently. Recent experimental studies have reported the beneficial influence of virtual reality training strategies on improving overall functional abilities for stroke survivors.Methods Conducted a systematic review of the literature using the following keywords to retrieve the data: stroke, virtual reality, motor deficits, neurorehabilitation, cognitive impairments, and sensory deficits. A random-effect meta-analysis was performed for seven scales – one cognitive (MMSE) and six motor (Fugl-Meyer, Berg Balance Scale, Time up and go, Wolf motor function, 10 m walk, Brunnstrom score)Objective To organize and compare all the available data regarding the effectiveness of virtual reality for stroke rehabilitationResults This literature reviewed 150 studies and included 46 for qualitative and 27 for quantitative analysis. There was no statistically significant difference between groups in MMSE score (MD = 0.24, 95%CI = ((−0.42) -(0.9)), p = .47, I2 = 0%) and Fugl-Meyer score (MD = (−0.38), 95%CI = ((−12.88)-(12.11)), p = .95, I2 = 98%) . The statistical significance was not reached in any of the other outcomes.Conclusions This review supports that stroke rehabilitation programs incorporating virtual reality are associated with improved functional outcomes, but there is no statistically significant difference compared to standard therapy.
Direct mechanical thrombectomy without intravenous thrombolysis versus bridging therapy for acute ischemic stroke: A meta-analysis of randomized controlled trialsAnna Podlasek, Permesh Singh Dhillon, Waleed Butt et al.|International Journal of Stroke|2021 Background Direct mechanical thrombectomy may result in similar outcomes compared to a bridging approach with intravenous thrombolysis (IVT + MT) in acute ischemic stroke. Recent randomized controlled trials have varied in their design and noninferiority margin. Aim We sought to meta-analyze accumulated trial data to assess the difference and non-inferiority in clinical and procedural outcomes between direct mechanical thrombectomy and bridging therapy. Summary of review We conducted a systematic review of electronic databases following the preferred reporting items for systematic reviews and meta-analyses guidelines. Random effects meta-analyses were conducted for the pooled data. The primary outcome was good functional outcome at 90 days (modified Rankin scale (mRS) ≤ 2). Secondary outcomes included excellent functional outcome (mRS ≤ 1), mortality, any intracranial hemorrhage, symptomatic intracranial hemorrhage, successful reperfusion (thrombolysis in cerebral infarction ≥ 2 b), and procedure-related complications. Four randomized controlled trials comprising 1633 patients (817 direct mechanical thrombectomy, 816 bridging therapy) were included. There were no statistical differences for the 90-day good functional outcome (OR = 1.02, 95% CI 0.84–1.25, p = 0.54, I 2 = 0%), and the absolute risk difference was 1% (95% CI: −4% to 5%). The lower 95% CI falls within the strictest noninferiority margin of −10% among included randomized control trials. Direct mechanical thrombectomy reduced the odds of successful reperfusion (OR = 0.76, 95% CI: 0.60–0.97, p = 0.03, I 2 = 0%) and any intracranial hemorrhage (OR = 0.65, 95% CI: 0.49–0.86, p = 0.003, I 2 = 38%). There was no difference in the remaining secondary outcomes. The risk of bias for all studies was low. Conclusion The combined trial data assessing direct mechanical thrombectomy versus bridging therapy showed no difference in improving good functional outcome. The wide noninferiority thresholds set by individual trials are in contrast with the clinical consensus on minimally important differences. However, our pooled analysis indicates noninferiority of direct mechanical thrombectomy with a 4% margin of confidence. The application of these findings is limited to patients presenting directly to mechanical thrombectomy-capable centers and real-world workflow times may differ against those achieved in a trial setting.
Factors Associated With the Decision-Making on Endovascular Thrombectomy for the Management of Acute Ischemic StrokeBackground and Purpose— Little is known about the real-life factors that clinicians use in selection of patients that would receive endovascular treatment (EVT) in the real world. We sought to determine patient, practitioner, and health system factors associated with therapeutic decisions around endovascular treatment. Methods— We conducted a multinational cross-sectional web-based study comprising of 607 clinicians and interventionalists from 38 countries who are directly involved in acute stroke care. Participants were randomly allocated to 10 from a pool of 22 acute stroke case scenarios. Each case was classified as either Class I, Class II, or unknown evidence according to the current guidelines. We used logistic regression analysis applying weight of evidence approach. Main outcome measures were multilevel factors associated with EVT, adherence to current EVT guidelines, and practice gaps between current and ideal practice settings. Results— Of the 1330 invited participants, 607 (45.6%) participants completed the study (53.7% neurologists, 28.5% neurointerventional radiologists, 17.8% other clinicians). The weighed evidence approach revealed that National Institutes of Health Stroke Scale (34.9%), level of evidence (30.2%), ASPECTS (Alberta Stroke Program Early CT Score) or ischemic core volume (22.4%), patient’s age (21.6%), and clinicians’ experience in EVT use (19.3%) are the most important factors for EVT decision. Of 2208 responses that met Class I evidence for EVT, 1917 (86.8%) were in favor of EVT. In case scenarios with no available guidelines, 1070 of 1380 (77.5%) responses favored EVT. Comparison between current and ideal practice settings revealed a small practice gap (941 of 6070 responses, 15.5%). Conclusions— In this large multinational survey, stroke severity, guideline-based level of evidence, baseline brain imaging, patients’ age and physicians’ experience were the most relevant factors for EVT decision-making. The high agreement between responses and Class I guideline recommendations and high EVT use even when guidelines were not available reflect the real-world acceptance of EVT as standard of care in patients with disabling acute ischemic stroke.