Association Between CT Angiogram Collaterals and CT Perfusion in Delayed Time Windows for Large Vessel Occlusion Ischemic Strokes

Background and Purpose: The Alberta Stroke Program Early Computed Tomography (CT) Score (ASPECTS) and CT perfusion (CTP) are commonly used to predict the ischemic core in acute ischemic strokes. CT angiography source images (CTA-SI) can also provide additional information to identify the extent of ischemia. Our objective was to investigate the correlation of noncontrast CT (NCCT) ASPECTS and CTA-SI ASPECTS with CTP core volumes. Methods: We utilized a single institutional, retrospective registry of consecutive patients with acute ischemic stroke with large vessel occlusion between May 2016 and May 2018. We graded ASPECTS both on baseline NCCT and CTA-SI and measured CTP core using automated RAPID software (cerebral blood flow <30%). We used Spearman’s correlation coefficients to evaluate the correlation between continuous variables. Results: A total of 52 patients fit the inclusion criteria of large vessel occlusion in 6 to 24 hours and baseline imaging work up of NCCT, CTA, and CTP. The median age was 63 (interquartile range=53.5–75) and 38.46% were female. The median NCCT ASPECTS was 7 (interquartile range=6–9), CTA-SI ASPECTS was 5 (interquartile range=4–7), and CTP core was 14.5 mL (interquartile range=0–46 mL). There was a moderate correlation between NCCT ASPECTS and CTP core (r s =−0.55, P <0.0001) and between CTA-SI ASPECTS and CTP core (r s =−0.50, P =0.0002). The optimal NCCT ASPECTS cutoff score to detect CTP core ≤70 mL was ≥6 (sensitivity, 0.84; specificity, 0.57; positive predictive value, 0.93; negative predictive value, 0.36) and the optimal CTA-SI ASPECTS was ≥5 (sensitivity, 0.76; specificity, 0.71; positive predictive value, 0.94; negative predictive value, 0.31). Conclusions: There was a moderate correlation between NCCT and CTA-SI ASPECTS in predicting CTP defined ischemic core in delayed time windows. Further studies are needed to determine if NCCT and CTA imaging could be used for image-based patient selection when CTP imaging is not available.

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Epidemiological Surveillance of the Impact of the COVID-19 Pandemic on Stroke Care Using Artificial Intelligence

Stroke ◽

10.1161/strokeaha.120.031960 ◽

2021 ◽

Author(s):

Raul G. Nogueira ◽

Jason M. Davies ◽

Rishi Gupta ◽

Ameer E. Hassan ◽

Thomas Devlin ◽

...

Keyword(s):

Artificial Intelligence ◽

Acute Stroke ◽

Systems Of Care ◽

Ct Perfusion ◽

Stroke Care ◽

Large Vessel ◽

Large Vessel Occlusion ◽

Vessel Occlusion ◽

Number Of Patients ◽

The Impact

Background and Purpose: The degree to which the coronavirus disease 2019 (COVID-19) pandemic has affected systems of care, in particular, those for time-sensitive conditions such as stroke, remains poorly quantified. We sought to evaluate the impact of COVID-19 in the overall screening for acute stroke utilizing a commercial clinical artificial intelligence platform. Methods: Data were derived from the Viz Platform, an artificial intelligence application designed to optimize the workflow of patients with acute stroke. Neuroimaging data on suspected patients with stroke across 97 hospitals in 20 US states were collected in real time and retrospectively analyzed with the number of patients undergoing imaging screening serving as a surrogate for the amount of stroke care. The main outcome measures were the number of computed tomography (CT) angiography, CT perfusion, large vessel occlusions (defined according to the automated software detection), and severe strokes on CT perfusion (defined as those with hypoperfusion volumes >70 mL) normalized as number of patients per day per hospital. Data from the prepandemic (November 4, 2019 to February 29, 2020) and pandemic (March 1 to May 10, 2020) periods were compared at national and state levels. Correlations were made between the inter-period changes in imaging screening, stroke hospitalizations, and thrombectomy procedures using state-specific sampling. Results: A total of 23 223 patients were included. The incidence of large vessel occlusion on CT angiography and severe strokes on CT perfusion were 11.2% (n=2602) and 14.7% (n=1229/8328), respectively. There were significant declines in the overall number of CT angiographies (−22.8%; 1.39–1.07 patients/day per hospital, P <0.001) and CT perfusion (−26.1%; 0.50–0.37 patients/day per hospital, P <0.001) as well as in the incidence of large vessel occlusion (−17.1%; 0.15–0.13 patients/day per hospital, P <0.001) and severe strokes on CT perfusion (−16.7%; 0.12–0.10 patients/day per hospital, P <0.005). The sampled cohort showed similar declines in the rates of large vessel occlusions versus thrombectomy (18.8% versus 19.5%, P =0.9) and comprehensive stroke center hospitalizations (18.8% versus 11.0%, P =0.4). Conclusions: A significant decline in stroke imaging screening has occurred during the COVID-19 pandemic. This analysis underscores the broader application of artificial intelligence neuroimaging platforms for the real-time monitoring of stroke systems of care.

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Abstract TP77: Impact of Time and Aspects on Clinical Core Mismatch in Large Vessel Occlusion Strokes

Stroke ◽

10.1161/str.51.suppl_1.tp77 ◽

2020 ◽

Vol 51 (Suppl_1) ◽

Author(s):

Shashvat Desai ◽

Bradley J Molyneaux ◽

Marcelo Rocha ◽

Matthew Starr ◽

Tudor G Jovin ◽

...

Keyword(s):

Patient Selection ◽

Time Window ◽

Ct Perfusion ◽

Large Vessel ◽

Large Vessel Occlusion ◽

Vessel Occlusion ◽

Ct Head ◽

Ischemic Core ◽

The Impact ◽

Core Volume

Introduction: Patient selection for endovascular thrombectomy (EVT) for anterior circulation large vessel occlusion (LVO) strokes in the 6-24-hour time window is dependent on delineating clinical core mismatch (CCM) as defined by DAWN trial criteria. In contrast, patient selection in the early window (0-6 hours) can be performed using ASPECTS on CT head. We aim to determine the prevalence of DAWN-CCM in LVO strokes and the impact of time and ASPECTS. Methods: Retrospective analysis of large vessel occlusion [internal carotid and middle cerebral artery-M1] strokes at a CSC. Consecutive patients who underwent CT perfusion or MRI within 120 minutes of CT head were included in the study (treated and untreated). Ischemic core volume was assessed using RAPID [IschemaView] and ASPECTS using automated ASPECTS [Brainomix]. CCM was defined using DAWN trial criteria [DAWN-CCM: NIHSS ≥10 and core <31 ml, NIHSS ≥20 and core <51 ml]. Results: A total of 116 patients were included. Mean age was 71 ±14 and 62% were females. Mean ischemic core volume and median ASPECTS were 46 ±65 ml and 8 (6-9), respectively. In patients with NIHSS score ≥10 (98), 57% had DAWN-CCM in the 0-24-hour window. Proportion of patients with DAWN-CCM in 6-24-hour window was 70% (6-12 hours), 50% (12-18 hours), and 50% (18-24 hours) [p=0.35]. Proportion of patients with DAWN-CCM by ASPECTS group was 88% (ASPECTS 9-10), 64% (ASPECTS 6-8) and 13% (ASPECTS 0-5) [p=<0.01] (Figure 1). Probability of DAWN-CCM declines by 7% for every 2 hours increase in TLKW to imaging, and by 13% for every 1-point decrease in ASPECTS. Conclusion: Approximately 57% of LVO strokes have clinical core mismatch. LVO strokes with DAWN-CCM decline with increasing time and decreasing ASPECTS. ASPECTS alone may be sufficient to identify patients with DAWN-CCM in a resource limited setting and avoid time consuming advanced imaging.

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Abstract WP82: Ghost Infarct Core: Ischemic Oreoverestimation by Admission CT Perfusion on Large Vessel Occlusion Stroke Patients

Stroke ◽

10.1161/str.50.suppl_1.wp82 ◽

2019 ◽

Vol 50 (Suppl_1) ◽

Author(s):

Gabriel M Rodrigues ◽

Michael Frankel ◽

Diogo C Haussen ◽

Raul G Nogueira

Keyword(s):

Ct Perfusion ◽

Large Vessel ◽

Large Vessel Occlusion ◽

Stroke Patients ◽

Infarct Core ◽

Vessel Occlusion

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Initial hospital management of patients with emergent large vessel occlusion (ELVO): report of the standards and guidelines committee of the Society of NeuroInterventional Surgery

Journal of NeuroInterventional Surgery ◽

10.1136/neurintsurg-2015-011984 ◽

2015 ◽

Vol 9 (3) ◽

pp. 316-323 ◽

Cited By ~ 64

Author(s):

Ryan A McTaggart ◽

Sameer A Ansari ◽

Mayank Goyal ◽

Todd A Abruzzo ◽

Barb Albani ◽

...

Keyword(s):

Ct Perfusion ◽

Imaging Techniques ◽

Hospital Management ◽

Clinical Severity ◽

Large Vessel ◽

Stroke Severity ◽

Large Vessel Occlusion ◽

Vessel Occlusion ◽

Initial Hospital ◽

Iv Tpa

ObjectiveTo summarize the current literature regarding the initial hospital management of patients with acute ischemic stroke (AIS) secondary to emergent large vessel occlusion (ELVO), and to offer recommendations designed to decrease the time to endovascular treatment (EVT) for appropriately selected patients with stroke.MethodsUsing guidelines for evidenced-based medicine proposed by the Stroke Council of the American Heart Association, a critical review of all available medical literature supporting best initial medical management of patients with AIS secondary to ELVO was performed. The purpose was to identify processes of care that most expeditiously determine the eligibility of a patient with an acute stroke for interventions including intravenous fibrinolysis with recombinant tissue plasminogen activator (IV tPA) and EVT using mechanical embolectomy.ResultsThis review identifies four elements that are required to achieve timely revascularization in ELVO. (1) In addition to non-contrast CT (NCCT) brain scan, CT angiography should be performed in all patients who meet an institutional threshold for clinical stroke severity. The use of any advanced imaging beyond NCCT should not delay the administration of IV tPA in eligible patients. (2) Activation of the neurointerventional team should occur as soon as possible, based on either confirmation of large vessel occlusion or a prespecified clinical severity threshold. (3) Additional imaging techniques, particularly those intended to physiologically select patients for EVT (CT perfusion and diffusion–perfusion mismatch imaging), may provide additional value, but should not delay EVT. (4) Routine use of general anesthesia during EVT procedures, should be avoided if possible. These workflow recommendations apply to both primary and comprehensive stroke centers and should be tailored to meet the needs of individual institutions.ConclusionsPatients with ELVO are at risk for severe neurologic morbidity and mortality. To achieve the best possible clinical outcomes stroke centers must optimize their triage strategies. Strategies that provide patients with ELVO with the fastest access to reperfusion depend upon detail-oriented process improvement.

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CT Perfusion Derived Hypoperfusion Intensity Ratio Predicts CTA Collateral Status in Large Vessel Occlusion Acute Ischemic Stroke.

10.26226/morressier.5e8335ba7cb08a046ef7c67f ◽

2020 ◽

Author(s):

Daniel Lyndon

Keyword(s):

Ischemic Stroke ◽

Acute Ischemic Stroke ◽

Intensity Ratio ◽

Ct Perfusion ◽

Large Vessel ◽

Large Vessel Occlusion ◽

Vessel Occlusion

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Impact of expanding large vessel occlusion thrombectomy time-windows in inner city Detroit

Brain Circulation ◽

10.4103/bc.bc_9_18 ◽

2018 ◽

Vol 4 (2) ◽

pp. 76

Author(s):

GaryB Rajah ◽

Hamidreza Saber ◽

Ali Luqman ◽

Sandra Narayanan

Keyword(s):

Inner City ◽

Time Windows ◽

Large Vessel ◽

Large Vessel Occlusion ◽

Vessel Occlusion

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E-076 Outcomes of large vessel occlusion thrombectomy in patients with CT perfusion defined large core stroke

10.1136/neurintsurg-2020-snis.110 ◽

2020 ◽

Author(s):

A Aghaebrahim ◽

S Desai ◽

A Monteiro ◽

M Granja ◽

G Agnoletto ◽

...

Keyword(s):

Ct Perfusion ◽

Large Vessel ◽

Large Vessel Occlusion ◽

Large Core ◽

Vessel Occlusion

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Abstract 39: CT Perfusion Selection May Lead to Better Clinical Outcomes Following Endovascular Therapy in Large Vessel Occlusion Stroke

Stroke ◽

10.1161/str.48.suppl_1.39 ◽

2017 ◽

Vol 48 (suppl_1) ◽

Author(s):

Mehdi Bouslama ◽

Diogo C Haussen ◽

Jonathan A Grossberg ◽

Seena Dehkharghani ◽

Meredith Bowen ◽

...

Keyword(s):

Endovascular Therapy ◽

Functional Outcomes ◽

Ct Perfusion ◽

Univariate Analysis ◽

Information Criterion ◽

Stent Retriever ◽

Large Vessel ◽

Control Analysis ◽

Large Vessel Occlusion ◽

Vessel Occlusion

Background and Purpose: Different imaging paradigms have been used to select patients for endovascular therapy (ET) in large vessel occlusion stroke (LVOS). We sought to determine whether CT perfusion (CTP) selection improves ET outcomes as compared to non-contrast CT (NCCT) alone. Methods: Review of a prospective single-center interventional database of consecutive patients between September 2010 and March 2016. Patients with anterior circulation strokes undergoing stent-retriever thrombectomy were categorized according to imaging selection: (1) CTP and (2) NCCT alone. Two separate analyses were performed: (1) Uni- and Multivariate analyses of the overall cohort and (2) Matched analysis based on age, baseline NIHSS, and glucose levels. Results: A total of 602 patients were included. CTP-selected patients (n=365; 61%) were younger (p=0.02) and had less comorbidities. On univariate analysis, CTP-selection was associated with higher rates of full reperfusion (mTICI-3, p<0.001), good outcomes (90-day mRS 0-2, p=0.005), lower mortality rates (p=0.005), and a favorable shift in the overall distribution of 90-day mRS (p<0.001) as compared with NCCT alone. The rates of any parenchymal hematoma were comparable between groups (p=0.671). Multivariate logistic regression showed that CTP was independently associated with mTICI-3 (OR=1.79 95%CI [1.27-2.53], p=0.001) and good outcomes (aOR=1.72 95%CI [1.10-2.67], p=0.017). In the matched case-control analysis (n=424 patients), CTP-selection was associated with a favorable shift in the distribution of 90-day mRS (p=0.016), lower 90-day mortality (p=0.02), higher rates of mTICI-3 reperfusion (p<0.001), and a trend towards higher rates of 90-day independence (p=0.06). There was an advantage in the ability of CTP to determine functional outcomes in patients presenting later than 6h (Akaike information criterion (AIC) 199.35 vs. 287.49 and Bayesian information criterion (BIC) 196.71 vs 283.27) and with an ASPECTS ≤7 (AIC 216.69 vs 334.96 and BIC 213.6 vs 329.94). Conclusion: CTP-based selection is associated with a favorable shift in functional outcomes in patients undergoing stent-retriever thrombectomy. Future prospective studies are warranted.

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