scholarly journals Assessing the Relative Value of CT Perfusion Compared to Non-contrast CT and CT Angiography in Prognosticating Reperfusion-Eligible Acute Ischemic Stroke Patients

2021 ◽  
Vol 12 ◽  
Author(s):  
Andrew Bivard ◽  
Christopher Levi ◽  
Longting Lin ◽  
Xin Cheng ◽  
Richard Aviv ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Acute Ischemic Stroke ◽  
Ct Angiography ◽  
Predictive Accuracy ◽  
Ct Perfusion ◽  
Imaging Modality ◽  
Characteristic Curve ◽  
Treatment Decision ◽  
Receiver Operator Characteristic Curve ◽  
Stroke Patients

In the present study we sought to measure the relative statistical value of various multimodal CT protocols at identifying treatment responsiveness in patients being considered for thrombolysis. We used a prospectively collected cohort of acute ischemic stroke patients being assessed for IV-alteplase, who had CT-perfusion (CTP) and CT-angiography (CTA) before a treatment decision. Linear regression and receiver operator characteristic curve analysis were performed to measure the prognostic value of models incorporating each imaging modality. One thousand five hundred and sixty-two sub-4.5 h ischemic stroke patients were included in this study. A model including clinical variables, alteplase treatment, and NCCT ASPECTS was weak (R2 0.067, P < 0.001, AUC 0.605) at predicting 90 day mRS. A second model, including dynamic CTA variables (collateral grade, occlusion severity) showed better predictive accuracy for patient outcome (R2 0.381, P < 0.001, AUC 0.781). A third model incorporating CTP variables showed very high predictive accuracy (R2 0.488, P < 0.001, AUC 0.899). Combining all three imaging modalities variables also showed good predictive accuracy for outcome but did not improve on the CTP model (R2 0.439, P < 0.001, AUC 0.825). CT perfusion predicts patient outcomes from alteplase therapy more accurately than models incorporating NCCT and/or CT angiography. This data has implications for artificial intelligence or machine learning models.

Abstract 1122‐000034: Systematic CT‐Perfusion acquisition in All Suspected Stroke Patients Increases Vascular Occlusion Detection and Thrombectomy Rates

2021 ◽  
Vol 1 (S1) ◽  
Author(s):  
Marta Olive‐Gadea ◽  
Manuel Requena ◽  
Facundo Diaz ◽  
Alvaro Garcia‐Tornel ◽  
Marta Rubiera ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Acute Ischemic Stroke ◽  
Clinical Symptoms ◽  
Ct Perfusion ◽  
False Negative ◽  
False Negative Rate ◽  
Vascular Occlusion ◽  
Stroke Patients ◽  
Imaging Protocols ◽  
The Impact

Introduction : In acute ischemic stroke patients, current guidelines recommend noninvasive vascular imaging to identify intracranial vessel occlusions (VO) that may benefit from endovascular treatment (EVT). However, VO can be missed in CT angiography (CTA) readings. We aim to evaluate the impact of consistently including CT perfusion (CTP) in admission stroke imaging protocols on VO diagnosis and EVT rates. Methods : We included patients with a suspected acute ischemic stroke that underwent urgent non‐contrast CT, CTA and CTP from April to October 2020. Hypoperfusion areas defined by Tmax>6s delay (RAPID software), congruent with the clinical symptoms and a vascular territory, were considered due to a VO (CTP‐VO). Cases in which mechanical thrombectomy was performed were defined as therapeutically relevant VO (EVT‐VO). For patients that received EVT, site of VO according to digital subtraction angiography was recorded. Two experienced neuroradiologists blinded to CTP but not to clinical symptoms, retrospectively evaluated NCCT and CTA to identify intracranial VO (CTA‐VO). We analyzed CTA‐VO sensitivity and specificity at detecting CTP‐VO and EVT‐VO respecitvely. We performed a logistic regression to test the association of Tmax>6s volumes with CTA‐VO identification and indication of EVT. Results : Of the 338 patients included in the analysis, 157 (46.5%) presented a CTP‐VO, (median Tmax>6s: 73 [29‐127] ml). CTA‐VO was identified in 83 (24.5%) of the cases. Overall CTA‐VO sensitivity for the detection of CTP‐VO was 50.3% and specificity was 97.8%. Higher hypoperfusion volume was associated with an increased CTA‐VO detection, with an odds ratio of 1.03 (95% confidence interval 1.02‐1.04) (figure). DSA was indicated in 107 patients; in 4 of them no EVT was attempted due to recanalization or a too distal VO in the first angiographic run. EVT was performed in 103 patients (30.5%. Tmax>6s: 102 [63‐160] ml), representing 65.6% of all CTP‐VO. Overall CTA‐VO sensitivity for the detection of EVT‐VO was 69.9%. The CTA‐VO sensitivity for detecting patients with indication of EVT according to clinical guidelines was as follows: 91.7% for ICA occlusions and 84.4% for M1‐MCA occlusions. For all other occlusion sites that received EVT, the CTA‐VO sensitivity was 36.1%. The overall specificity was 95.3%. Among patients who received EVT, CTA‐VO was not detected in 31 cases, resulting in a false negative rate of 30.1%. False negative CTA‐VO cases had lower Tmax>6s volumes (69[46‐99.5] vs 126[84‐169.5]ml, p<0.001) and lower NIHSS (13[8.5‐16] vs 17[14‐21], p<0.001). Conclusions : Systematically including CTP perfusion in the acute stroke admission imaging protocols may increase the diagnosis of VO and rate of EVT.

What is the impact of head movement on automated CT perfusion mismatch evaluation in acute ischemic stroke?

2021 ◽  
pp. neurintsurg-2021-017510
Author(s):  
Arne Potreck ◽  
Fatih Seker ◽  
Matthias Anthony Mutke ◽  
Charlotte Sabine Weyland ◽  
Christian Herweh ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Acute Ischemic Stroke ◽  
Head Movement ◽  
Ct Perfusion ◽  
Treatment Decision ◽  
Brain Perfusion ◽  
Left Middle Cerebral Artery ◽  
Ct Scanner ◽  
Infarct Core ◽  
The Impact

ObjectivesAutomated CT perfusion mismatch assessment is an established treatment decision tool in acute ischemic stroke. However, the reliability of this method in patients with head motion is unclear. We therefore sought to evaluate the influence of head movement on automated CT perfusion mismatch evaluation.MethodsUsing a realistic CT brain-perfusion-phantom, 7 perfusion mismatch scenarios were simulated within the left middle cerebral artery territory. Real CT noise and artificial head movement were added. Thereafter, ischemic core, penumbra volumes and mismatch ratios were evaluated using an automated mismatch analysis software (RAPID, iSchemaView) and compared with ground truth simulated values.ResultsWhile CT scanner noise alone had only a minor impact on mismatch evaluation, a tendency towards smaller infarct core estimates (mean difference of −5.3 (−14 to 3.5) mL for subtle head movement and −7.0 (−14.7 to 0.7) mL for strong head movement), larger penumbral estimates (+9.9 (−25 to 44) mL and +35 (−14 to 85) mL, respectively) and consequently larger mismatch ratios (+0.8 (−1.5 to 3.0) for subtle head movement and +1.9 (−1.3 to 5.1) for strong head movement) were noted in dependence of patient head movement.ConclusionsMotion during CT perfusion acquisition influences automated mismatch evaluation. Potentially treatment-relevant changes in mismatch classifications in dependence of head movement were observed and occurred in favor of mechanical thrombectomy.

Incidence and predictors of left atrium thrombus in acute ischemic stroke patients without atrial fibrillation: a single center cohort study

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
T Cinar ◽  
M.I Hayiroglu ◽  
V Cicek ◽  
S Asal ◽  
M.M Atmaca ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Cohort Study ◽  
Ischemic Stroke ◽  
Acute Ischemic Stroke ◽  
Left Atrium ◽  
Characteristic Curve ◽  
Multivariate Logistic Regression Analysis ◽  
Single Center ◽  
Stroke Patients ◽  
Previous Diagnosis

Abstract Introduction The present study aimed to determine independent predictors of left atrial thrombus (LAT) in acute ischemic stroke patients without atrial fibrillation (AF) using transesophageal echocardiography (TEE). Material and methods In this single center, retrospective cohort study, we enrolled 149 consecutive acute ischemic stroke patients. All of the patients underwent TEE examination to detect LAT within 10 days following admission. Multivariate logistic regression analysis was performed to assess independent predictors of LAT. Results Among all cases, 14 patients (9.3%) had a diagnosis of LAT on TEE examination. In a multivariate analysis; a previous diagnosis of cerebrovascular accident, elevated mean platelet volume (MPV), low left ventricle ejection fraction (EF) and a reduced left atrium appendix (LAA) peak emptying velocity were independent predictors of LAT. The area of MPV under the receiver operating characteristic curve analysis was 0.70 (95% CI: 0.57–0.83; p=0.011). With the optimal cut-off value of 9.45, MPV had a sensitivity of 71.4% and a specificity of 63% to predict LAT. Conclusion Patients with low ventricle EF and elevated MPV should undergo further TEE examination for the possibility of cardio-embolic source. In addition, this research may provide novel information with respect to the applicability of MPV to predict LAT in acute ischemic stroke patients without AF. Figure 1 Funding Acknowledgement Type of funding source: None

scholarly journals Prospective Endovascular Treatment in Acute Ischemic Stroke Evaluating Non-Contrast Head CT versus CT Perfusion (PLEASE No CTP)

2019 ◽  
Vol 8 (2-6) ◽  
pp. 116-122
Author(s):  
Ameer E. Hassan ◽  
Hafsah Shamim ◽  
Haralabos Zacharatos ◽  
Saqib A. Chaudhry ◽  
Christina Sanchez ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Ischemic Stroke ◽  
Endovascular Treatment ◽  
Acute Ischemic Stroke ◽  
Symptom Onset ◽  
Ct Perfusion ◽  
Treatment Decision ◽  
Anterior Circulation ◽  
Nihss Score ◽  
Contrast Ct

Background: Studies have shown a lack of agreement of computed tomography perfusion (CTP) in the selection of acute ischemic stroke (AIS) patients for endovascular treatment. Purpose: To demonstrate whether non-contrast computed tomography (CT) within 8 h of symptom onset is comparable to CTP imaging. Methods: Prospective study of consecutive anterior circulation AIS patients with a National Institute of Health Stroke Scale (NIHSS) score > 7 presenting within 8 h of symptom onset with endovascular treatment. All patients had non-contrast CT, CT angiography, and CTP. The neuro-interventionalist was blinded to the results of the CTP and based the treatment decision using the Alberta Stroke Program Early CT score (ASPECTS). Baseline demographics, co-morbidities, and baseline NIHSS scores were collected. Outcomes were modified Rankin scale (mRS) score at discharge and in-hospital mortality. Good outcomes were defined as a mRS score of 0–2. Results: 283 AIS patients were screened for the trial, and 119 were enrolled. The remaining patients were excluded for: posterior circulation stroke, no CTP performed, could not obtain consent, and NIHSS score < 7. Mean ­NIHSS score at admission was 16.8 ± 3, and mean ASPECTS was 8.4 ± 1.4. There was no statistically significant correlation with CTP penumbra and good outcomes: 50 versus 47.8% with no penumbra present (p = 0.85). In patients without evidence of CTP penumbra, there was 22.5% mortality compared to 22.1% mortality in patients with a CTP penumbra. If ASPECTS ≥7, 64.6% had good outcome versus 13.3% if ASPECTS < 7 (p < 0.001). Patients with an ASPECTS ≥7 had 10% mortality versus 51.4% in patients with an ASPECTS < 7 (p < 0.001). Conclusions: CTP penumbra did not identify patients who would benefit from endovascular treatment when patients were selected with non-contrast CT ASPECTS ≥7. There is no correlation of CTP penumbra with good outcomes or mortality. Larger prospective trials are warranted to justify the use of CTP within 6 h of symptom onset.

scholarly journals Intravenous thrombolysis in acute ischemic stroke patients with negative CT perfusion: a case series

2014 ◽  
Vol 3 (7) ◽  
pp. 204798161454321
Author(s):  
Ratnesh Mehra ◽  
Chiu Yuen To ◽  
Omar Qahwash ◽  
Boyd Richards ◽  
Richard D Fessler
Keyword(s):  
Ischemic Stroke ◽  
Acute Ischemic Stroke ◽  
Ct Perfusion ◽  
Case Series ◽  
Intravenous Thrombolysis ◽  
Hemorrhagic Transformation ◽  
Tissue Type ◽  
Stroke Patients ◽  
Radiographic Findings ◽  
Type Plasminogen Activator

Background Computed tomography perfusion (CTP) is a commonly used modality of neurophysiologic imaging to aid the selection of acute ischemic stroke patients for neuroendovascular intervention by identifying the presence of penumbra versus infarcted brain tissue. However many patients present with evidence of cerebral ischemia with normal CTP, and in that case, should intravenous thrombolytics be given? Purpose To demonstrate if tissue-type plasminogen activator (tPA)-eligible stroke patients without perfusion defects demonstrated on CTP would benefit from administration of intravenous thrombolytics. Material and Methods We retrospectively identified patients presenting with acute ischemic symptoms who received intravenous tPA (IV-tPA) from January to June 2012 without a perfusion defect on CTP. Clinical and radiographic findings including the NIHSS at presentation, 24 h, and at discharge, symptomatic and asymptomatic hemorrhagic transformation, and the modified Rankin score at 30 days were collected. A reduction of NIHSS of greater than 4 points or resolution of symptoms was considered significant. Results Seventeen patients were identified with a mean NIHSS of 8.2 prior to administration of intravenous thrombolytics, 3.5 after 24 h, and 2.5 at discharge. Among them, 13 patients had significant improvement of NIHSS with a mean reduction of 6.15 points at 24 h. One patient initially improved but had delayed hemorrhagic transformation and died. Two patients had improvement in NIHSS but were not significant and two patients had increased in NIHSS at 24 h, although one eventually improved at discharge. There was no asymptomatic hemorrhagic transformation. Mean mRS at 3 months is 1.76. Conclusion The failure to identify a perfusion deficit by CTP should not be used as a contraindication for intravenous thrombolytics. Criteria for administration of intravenous thrombolytics should still be based on time from symptom onset as previously published by NINDS.

Optimal thresholds for ischemic penumbra predicted by computed tomography perfusion in patients with acute ischemic stroke treated with mechanical thrombectomy

2017 ◽  
Vol 10 (3) ◽  
pp. 279-284 ◽  
Author(s):  
Katsuharu Kameda ◽  
Junji Uno ◽  
Ryosuke Otsuji ◽  
Nice Ren ◽  
Shintaro Nagaoka ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Acute Ischemic Stroke ◽  
Cerebral Blood Volume ◽  
Mechanical Thrombectomy ◽  
Ct Perfusion ◽  
Characteristic Curve ◽  
Mean Transit Time ◽  
Area Under The Curve ◽  
Ischemic Penumbra ◽  
Optimal Thresholds

Background and purposeOptimal thresholds for ischemic penumbra detected by CT perfusion (CTP) in patients with acute ischemic stroke (AIS) have not been elucidated. In this study we investigated optimal thresholds for salvageable ischemic penumbra and the risk of hemorrhagic transformation (HT).MethodsA total of 156 consecutive patients with AIS treated with mechanical thrombectomy (MT) at our hospital were enrolled. Absolute (a) and relative (r) CTP parameters including cerebral blood flow (aCBF and rCBF), cerebral blood volume (aCBV and rCBV), and mean transit time (aMTT and rMTT) were evaluated for their value in detecting ischemic penumbra in each of seven arbitrary regions of interest defined by the major supplying blood vessel. Optimal thresholds were calculated by performing receiver operating characteristic curve analysis in 47 patients who achieved Thrombolysis In Cerebral Infarction (TICI) grade 3 recanalization. The risk of HT after MT was evaluated in 101 patients who achieved TICI grade 2b–3 recanalization.ResultsAbsolute CTP parameters for distinguishing ischemic penumbra from ischemic core were as follows: aCBF, 27.8 mL/100 g/min (area under the curve 0.82); aCBV, 2.1 mL/100 g (0.75); and aMTT, 7.30 s (0.70). Relative CTP parameters were as follows: rCBF, 0.62 (0.81); rCBV, 0.83 (0.87); and rMTT, 1.61 (0.73). CBF was significantly lower in areas of HT than in areas of infarction (aCBF, p<0.01; rCBF, p<0.001).ConclusionsCTP may be able to predict treatable ischemic penumbra and the risk of HT after MT in patients with AIS.

The Prognostic Value of CT Angiography and CT Perfusion in Acute Ischemic Stroke

2015 ◽  
Vol 40 (5-6) ◽  
pp. 258-269 ◽  
Author(s):  
Tom van Seeters ◽  
Geert Jan Biessels ◽  
L. Jaap Kappelle ◽  
Irene C. van der Schaaf ◽  
Jan Willem Dankbaar ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Clinical Outcome ◽  
Acute Ischemic Stroke ◽  
Ct Angiography ◽  
Predictive Value ◽  
Prognostic Value ◽  
Ct Perfusion ◽  
Patient Characteristics ◽  
Poor Clinical Outcome ◽  
Poor Outcome

Background: CT angiography (CTA) and CT perfusion (CTP) are important diagnostic tools in acute ischemic stroke. We investigated the prognostic value of CTA and CTP for clinical outcome and determined whether they have additional prognostic value over patient characteristics and non-contrast CT (NCCT). Methods: We included 1,374 patients with suspected acute ischemic stroke in the prospective multicenter Dutch acute stroke study. Sixty percent of the cohort was used for deriving the predictors and the remaining 40% for validating them. We calculated the predictive values of CTA and CTP predictors for poor clinical outcome (modified Rankin Scale score 3-6). Associations between CTA and CTP predictors and poor clinical outcome were assessed with odds ratios (OR). Multivariable logistic regression models were developed based on patient characteristics and NCCT predictors, and subsequently CTA and CTP predictors were added. The increase in area under the curve (AUC) value was determined to assess the additional prognostic value of CTA and CTP. Model validation was performed by assessing discrimination and calibration. Results: Poor outcome occurred in 501 patients (36.5%). Each of the evaluated CTA measures strongly predicted outcome in univariable analyses: the positive predictive value (PPV) was 59% for Alberta Stroke Program Early CT Score (ASPECTS) ≤7 on CTA source images (OR 3.3; 95% CI 2.3-4.8), 63% for presence of a proximal intracranial occlusion (OR 5.1; 95% CI 3.7-7.1), 66% for poor leptomeningeal collaterals (OR 4.3; 95% CI 2.8-6.6), and 58% for a >70% carotid or vertebrobasilar stenosis/occlusion (OR 3.2; 95% CI 2.2-4.6). The same applied to the CTP measures, as the PPVs were 65% for ASPECTS ≤7 on cerebral blood volume maps (OR 5.1; 95% CI 3.7-7.2) and 53% for ASPECTS ≤7 on mean transit time maps (OR 3.9; 95% CI 2.9-5.3). The prognostic model based on patient characteristics and NCCT measures was highly predictive for poor clinical outcome (AUC 0.84; 95% CI 0.81-0.86). Adding CTA and CTP predictors to this model did not improve the predictive value (AUC 0.85; 95% CI 0.83-0.88). In the validation cohort, the AUC values were 0.78 (95% CI 0.73-0.82) and 0.79 (95% CI 0.75-0.83), respectively. Calibration of the models was satisfactory. Conclusions: In patients with suspected acute ischemic stroke, admission CTA and CTP parameters are strong predictors of poor outcome and can be used to predict long-term clinical outcome. In multivariable prediction models, however, their additional prognostic value over patient characteristics and NCCT is limited in an unselected stroke population.

Sign in / Sign up

Export Citation Format

Share Document