Intelligent, mobile stroke imaging

2021 ◽  
Author(s):  
Ian Fyfe
Keyword(s):  
Stroke Imaging

scholarly journals Interpreting CT perfusion in stroke

2018 ◽  
Vol 19 (2) ◽  
pp. 136-142 ◽  
Author(s):  
Stevan Christopher Wing ◽  
Hugh S Markus
Keyword(s):  
Acute Stroke ◽  
Perfusion Imaging ◽  
Treatment Time ◽  
Ct Perfusion ◽  
Time Windows ◽  
Onset Time ◽  
Brain Perfusion ◽  
Reperfusion Therapy ◽  
Imaging Protocol ◽  
Stroke Imaging

CT perfusion images can be rapidly obtained on all modern CT scanners and easily incorporated into an acute stroke imaging protocol. Here we discuss the technique of CT perfusion imaging, how to interpret the data and how it can contribute to the diagnosis of acute stroke and selection of patients for treatment. Many patients with acute stroke are excluded from reperfusion therapy if the onset time is not known or if they present outside of traditional treatment time windows. There is a growing body of evidence supporting the use of perfusion imaging in these patients to identify patterns of brain perfusion that are favourable for recanalisation therapy.

scholarly journals Acute Stroke Imaging Research Roadmap

Stroke ◽  
2008 ◽  
Vol 39 (5) ◽  
pp. 1621-1628 ◽  
Author(s):  
Max Wintermark ◽  
Gregory W. Albers ◽  
Andrei V. Alexandrov ◽  
Jeffry R. Alger ◽  
Roland Bammer ◽  
...  
Keyword(s):  
Acute Stroke ◽  
Stroke Imaging ◽  
Imaging Research ◽  
Acute Stroke Imaging

scholarly journals The Predictive Value of the Boston Acute Stroke Imaging Scale (BASIS) in Acute Ischemic Stroke Patients among Chinese Population

PLoS ONE ◽  
2014 ◽  
Vol 9 (12) ◽  
pp. e113967
Author(s):  
Yuanqi Zhao ◽  
Min Zhao ◽  
Xiaomin Li ◽  
Xiancong Ma ◽  
Qinghao Zheng ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Acute Stroke ◽  
Acute Ischemic Stroke ◽  
Predictive Value ◽  
Chinese Population ◽  
Stroke Patients ◽  
Stroke Imaging ◽  
Acute Stroke Imaging

Cervical ICA pseudo-occlusion on single phase CTA in patients with acute terminal ICA occlusion: what is the mechanism and can delayed CTA aid diagnosis?

2018 ◽  
Vol 10 (10) ◽  
pp. 983-987 ◽  
Author(s):  
James Wareham ◽  
Robert Crossley ◽  
Sarah Barr ◽  
Alex Mortimer
Keyword(s):  
Ophthalmic Artery ◽  
Single Phase ◽  
Internal Carotid ◽  
Posterior Communicating Artery ◽  
Digital Subtraction ◽  
Delayed Imaging ◽  
Stroke Imaging ◽  
Cervical Segment ◽  
Digital Subtraction Angiographic ◽  
Delayed Phase

BackgroundSingle-phase CT angiography (CTA) forms the basis of hyperacute stroke imaging but many patients with terminal internal carotid artery (ICA) occlusion exhibit a pseudo-occlusion of the cervical ICA whereby a column of unopacified blood mimics a tandem cervical ICA lesion. We aimed to investigate the utility of a delayed phase acquisition to aid identification of a pseudo-occlusion and investigated the mechanism for this imaging artefact.MethodsThirteen patients with a pseudo-occlusion were compared with 13 patients without. CT, CTA, and digital subtraction angiographic images were reviewed by two interventional neuroradiologists for extension of thrombus into the ophthalmic segment, filling of the posterior communicating artery and ophthalmic artery, and for extension of contrast beyond the cervical segment and outline of the proximal clot surface by contrast on delayed imaging performed at 40 or 80 s.ResultsThose with a pseudo-occlusion demonstrated more frequent thrombus extension into the ophthalmic segment (100% vs 23%, P=0.0001), less frequent filling of the posterior communicating artery (15% vs 85%, P=0.0012), and less frequent filling of the ophthalmic artery (15% vs 92%, P=0.0002) compared with those without a pseudo-occlusion. Delayed CTA imaging showed contrast beyond the cervical segment and meeting the proximal clot face in 2/11 patients. Each of these two patients showed patency of the posterior communicating artery origin.ConclusionThrombus extension into the ophthalmic segment and patency of the posterior communicating artery and ophthalmic artery seem to govern whether a patient with a terminal ICA occlusion exhibits a pseudo-occlusion. Delayed imaging was of limited value in identification of a pseudo-occlusion.

Abstract T P29: The Impact of Contrast Based CTA/CTP Brain Attack Protocol on Kidney Function

Stroke ◽  
2015 ◽  
Vol 46 (suppl_1) ◽  
Author(s):  
Jamie Folsom ◽  
Nnadozie Ezerioha ◽  
Pratik Chhatbar ◽  
Swaroop Pawar ◽  
Christina Holmstedt ◽  
...  
Keyword(s):  
Acute Stroke ◽  
Creatinine Level ◽  
Endovascular Therapy ◽  
Kidney Injury ◽  
Complete Information ◽  
Absolute Increase ◽  
Stroke Imaging ◽  
Clinical Consequences ◽  
Stage Renal Disease ◽  
The Impact

Background: We aimed to evaluate the occurrence of acute kidney injury (AKI) associated with contrast based CTA/CTP Brain Attack (BAT) Protocol in a cohort of patients who presented to an academic stroke center with acute stroke symptoms. Methods: Consecutive patients who presented to the Emergency Department with acute stroke symptoms from 01/12 to 12/12 and received CTA/CTP contrast-based BAT protocol were identified and their medical records reviewed. Clinicodemographic information was retrieved. Serum creatinine values at baseline, at discharge, and at a follow-up visit, as well as the highest in-hospital value were recorded. AKI was defined as a 0.3 absolute increase in creatinine level from baseline. A logistic regression was fit to identify the potential predictors for AKI. Results: Of 348 patients had complete information. 37(11%) patients experienced AKI during hospitalization. Of 38 patients, 16 (43%) patients had persistent elevated creatinine at hospital discharge (5 patients also received endovascular therapy); 11(38%) patients returned to baseline, and the rest 10(26%) patients’ creatinine improved but did not return to baseline. No patient develops end stage renal disease requiring hemodialysis. Baseline creatinine level (p<0.002), comorbidity index (p=0.05) and endovascular therapy (p=0.01) were the three main predictors of AKI. Race, gender and age were not predictors of AKI. Conclusion: Contrast based CTA/CTP BAT protocol may incur a small risk of AKI in patients but clinical consequences are minimal. Risks seem greater in patients with higher presenting creatinine level, more comorbidities and those receiving additional contrast from endovascular therapy. More data are required to understand the clinical impact of contrast-based CT stroke imaging protocols.

Abstract TP47: Intracranial Intraplaque Hemorrhage in Acute Stroke: Interim Results of the Stroke Imaging Package Study

Stroke ◽  
2017 ◽  
Vol 48 (suppl_1) ◽  
Author(s):  
Changyun Liu ◽  
Huisheng Chen ◽  
Yi Yang ◽  
Jun Xu ◽  
Meng Zhang ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Acute Stroke ◽  
Clinical Importance ◽  
Chinese Patients ◽  
Intraplaque Hemorrhage ◽  
Large Artery ◽  
Ischemic Event ◽  
Stroke Imaging ◽  
Medical Centers ◽  
Conventional Mri

Introdution: Intracranial artery atherosclerosis is an important cause of ischemic stroke, especially in people of Asian origin. Intraplaque hemorrhage is supposed to be a predictor of ischemic event. The goal of this study was to examine the occurrence of intraplaque hemorrhage in a large cohort of Chinese patients with acute ischemic stroke. Methods: Patients with first ever stroke within 72 hours from onset, confirmed by diffusion weighted imaging, were recruited from 16 medical centers. Conventional MRI, magnetic resonance angiography, HRMRI (including 3-dimentional T1 images and 2-dimentional T2 images), and SWI were performed. Intraplaque hemorrhage was identified if hyperintense signals on 3-dimentional T1 images of HRMRI were observed within intracranial plaques. Results: Six hundred and one patients (70% male, mean age 61±16 years old, mean NIHSS 6± 5) were enrolled. Median time from symptom onset to MRI was 44 ± 20 hours. Of them, 240(40%) were diagnosed with large artery atherosclerosis (LAA) stroke. Intracranial intraplaque hemorrhage was identified in 15 intracranial plaques of 13 patients with LAA stroke. Six plaques with intraplaque hemorrhage were asymptomatic and irrelevant to ischemic infarct lesions. In 2 patients, both symptomatic and asymptomatic intraplaque hemorrhage were observed. Conclusions: The prevalence of intracranial intraplaque hemorrhage was low (5.4%)in acute stroke patients. The clinical importance of asymptomatic intraplaque hemorrhage need further investigations.

Abstract 13: Corticospinal Tract Injury Estimated From Acute Stroke Imaging Predicts Upper Extremity Motor Recovery After Stroke

Stroke ◽  
2020 ◽  
Vol 51 (Suppl_1) ◽  
Author(s):  
David J Lin ◽  
Alison M Cloutier ◽  
Kimberly S Erler ◽  
Jessica M Cassidy ◽  
Samuel B Snider ◽  
...  
Keyword(s):  
Acute Stroke ◽  
Upper Extremity ◽  
Corticospinal Tract ◽  
Standard Of Care ◽  
Major Effect ◽  
Motor Recovery ◽  
Post Stroke ◽  
Stroke Imaging ◽  
Recovery Potential ◽  
Structural Injury

Introduction: Injury to the corticospinal tract (CST) has been shown to have a major effect on upper extremity motor recovery after stroke. This study aimed to examine how well CST injury, measured from neuroimaging acquired during the acute stroke workup, predicts upper extremity motor recovery. Methods: Patients (N = 48) with upper extremity weakness after ischemic stroke were assessed using the upper extremity Fugl-Meyer (FM) during the acute stroke hospitalization and again at 3-month follow-up. CST injury was quantified and compared, using four different methods, from images obtained as part of the stroke standard-of-care workup. Logistic and linear regression were performed using CST injury to predict delta FM. Injury to primary motor and premotor cortices were included as potential modifiers of the effect of CST injury on recovery. Results: 48 patients were enrolled 4.2 ± 2.7 days post-stroke and completed this study. CST injury distinguished patients who reached their recovery potential (as predicted from initial impairment) from those who did not, with AUC values ranging from 0.75 to 0.8. In addition, CST injury explained ~20% of the variance in the magnitude of upper extremity recovery, even after controlling for the severity of initial impairment. Results were consistent when comparing four different methods of measuring CST injury. Extent of injury to primary motor and premotor cortices did not significantly influence the predictive value that CST injury had for recovery. Conclusions: Structural injury to the CST, as estimated from standard-of-care imaging available during the acute stroke hospitalization, is a robust way to distinguish patients who achieve their predicted recovery potential and explains a significant amount of the variance in post-stroke upper extremity motor recovery.

Abstract W P27: Quantitative Measurement Of Blood Flow Around Intravascular Thrombus Using CT Perfusion T0 Maps

Stroke ◽  
2015 ◽  
Vol 46 (suppl_1) ◽  
Author(s):  
Seong Hwan Ahn ◽  
Christopher D. d’Esterre ◽  
Emmad M Qazi ◽  
Mayank Goyal ◽  
Andrew M Demchuk ◽  
...  
Keyword(s):  
Blood Flow ◽  
Predictive Value ◽  
Arterial Input Function ◽  
Ct Perfusion ◽  
Regression Line ◽  
Input Function ◽  
Positive Slope ◽  
Arterial Tree ◽  
Stroke Imaging ◽  
Iv Tpa

Introduction: Anterograde blood flow around thrombus and extent of retrograde collateral filling can affect thrombus lysis with IV tPA. Current assessment of blood flow around thrombus is however very subjective. The aim of the present study is to validate a newly devised method to quantify blood flow around thrombus using CT perfusion (CTP) T0 maps. Methods: From the Prove-IT stroke-imaging database, perfusion CT and DSA images of stroke patients treated with IV tPA and/or IA thrombolysis were analyzed. We generated maps that measure delay in arrival time of contrast within the intracranial arterial tree (T0 maps) from that of the chosen arterial input function. A “positive sloped” regression line of T0 values from distal clot interface to at least 14 pixels (median 68 pixels) along the artery profile indicated presence of occult anterograde flow. Anterograde flow thus measured using the T0 maps was compared with anterograde flow assessed on first angiography of subsequent IA procedure. Results: Of 37 patients (mean age 66 ± 13.5 years, 20 female), 35 (94.6%) were treated with IV tPA before DSA. Median time from CTP to first run angiography was 83 mins (IQR 53-100 mins). Positive slope were noted in 10 patients. Patients who had anterograde flow on first angiography were 10. Compared with anterograde flow on first run angio, positive slope on T0 map had a sensitivity of 80%, specificity of 92.6% and a positive predictive value of 80% and negative predictive value of 92.6%. In patients with anterograde flow on first angiography, median T0 time at proximal clot interface was 0.1 seconds (IQR 0-0.1) and at distal clot interface was 0.7 seconds (IQR 0.5-3.1). In patients without any anterograde flow on first angio, median T0 time at proximal clot interface was 0.1 seconds (IQR 0-0.3) while that at distal clot interface was 3.7 seconds (IQR 2.1-5.6). Conclusions: The slope method on CTP T0 maps and measurement of T0 values around clot reliably measure presence of anterograde blood flow through thrombus.

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