scholarly journals Strategies of Collateral Blood Flow Assessment in Ischemic Stroke: Prediction of the Follow-Up Infarct Volume in Conventional and Dynamic CTA

2014 ◽  
Vol 36 (3) ◽  
pp. 488-494 ◽  
Author(s):  
S.E. Beyer ◽  
K.M. Thierfelder ◽  
L. von Baumgarten ◽  
M. Rottenkolber ◽  
F.G. Meinel ◽  
...  
Keyword(s):  
Blood Flow ◽  
Ischemic Stroke ◽  
Infarct Volume ◽  
Collateral Blood Flow

scholarly journals Computed Tomography Perfusion–Based Machine Learning Model Better Predicts Follow-Up Infarction in Patients With Acute Ischemic Stroke

Stroke ◽  
2021 ◽  
Vol 52 (1) ◽  
pp. 223-231
Author(s):  
Hulin Kuang ◽  
Wu Qiu ◽  
Anna M. Boers ◽  
Scott Brown ◽  
Keith Muir ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Ischemic Stroke ◽  
Acute Ischemic Stroke ◽  
Infarct Volume ◽  
Interquartile Range ◽  
Time Dependent ◽  
Computed Tomography Perfusion

Background and Purpose: Prediction of infarct extent among patients with acute ischemic stroke using computed tomography perfusion is defined by predefined discrete computed tomography perfusion thresholds. Our objective is to develop a threshold-free computed tomography perfusion–based machine learning (ML) model to predict follow-up infarct in patients with acute ischemic stroke. Methods: Sixty-eight patients from the PRoveIT study (Measuring Collaterals With Multi-Phase CT Angiography in Patients With Ischemic Stroke) were used to derive a ML model using random forest to predict follow-up infarction voxel by voxel, and 137 patients from the HERMES study (Highly Effective Reperfusion Evaluated in Multiple Endovascular Stroke Trials) were used to test the derived ML model. Average map, T max , cerebral blood flow, cerebral blood volume, and time variables including stroke onset-to-imaging and imaging-to-reperfusion time, were used as features to train the ML model. Spatial and volumetric agreement between the ML model predicted follow-up infarct and actual follow-up infarct were assessed. Relative cerebral blood flow <0.3 threshold using RAPID software and time-dependent T max thresholds were compared with the ML model. Results: In the test cohort (137 patients), median follow-up infarct volume predicted by the ML model was 30.9 mL (interquartile range, 16.4–54.3 mL), compared with a median 29.6 mL (interquartile range, 11.1–70.9 mL) of actual follow-up infarct volume. The Pearson correlation coefficient between 2 measurements was 0.80 (95% CI, 0.74–0.86, P <0.001) while the volumetric difference was −3.2 mL (interquartile range, −16.7 to 6.1 mL). Volumetric difference with the ML model was smaller versus the relative cerebral blood flow <0.3 threshold and the time-dependent T max threshold ( P <0.001). Conclusions: A ML using computed tomography perfusion data and time estimates follow-up infarction in patients with acute ischemic stroke better than current methods.

Abstract P321: The Cerebral Collateral Cascade: Rethinking the Assessment of Vascular Pathways in Acute Ischemic Stroke Patients

Stroke ◽  
2021 ◽  
Vol 52 (Suppl_1) ◽  
Author(s):  
Tobias D Faizy ◽  
Michael Mlynash ◽  
Reza Kabiri ◽  
Soren Christensen ◽  
Gabriella Kuraitis ◽  
...  
Keyword(s):  
Blood Flow ◽  
Ischemic Stroke ◽  
Acute Ischemic Stroke ◽  
Ct Perfusion ◽  
Infarct Volume ◽  
Strong Predictor ◽  
Secondary Outcome ◽  
Collateral Blood Flow ◽  
Vessel Occlusion ◽  
Cortical Vein

Background and Purpose: Robust collateral blood flow in patients with acute ischemic stroke due to large vessel occlusion (AIS-LVO) has been correlated with favorable outcomes. Collaterals are commonly assessed by the number of arteries present on non-invasive CT angiography (CTA) overlying ischemic brain, but blood transit from these arteries through the brain tissue and the venous drainage is not assessed by this technique. We hypothesized that a comprehensive imaging analysis of the cerebral collateral cascade (CCC) would predict clinical and radiological outcomes in patients with AIS-LVO patients. Materials and Methods: Multicenter retrospective cohort study of AIS-LVO patients undergoing thrombectomy triage. CCC was determined on pre-treatment imaging by scoring for pial arterial collaterals, tissue-level collaterals (TLC), and venous outflow. Pial arterial collaterals were determined by CTA (Tan scale), TLC were assessed on CT perfusion data using the Hypoperfusion Intensity Ratio, and venous egress was assessed on CTA using the cortical vein opacification score system. 3 groups were defined: CCC+ (good pial collaterals, TLC, and venous perfusion), CCC- (poor pial collaterals, TLC, and venous perfusion) and CCCmixed (reminder of patients). Primary outcome was a good functional outcome (modified Rankin Scale [mRS] 0-2 at 90 days). Secondary outcome was final infarct volume. Results: 647 patients met inclusion criteria: 176 CCC+, 345 CCCmixed and 126 CCC-. Multivariate ordinal logistic regression showed that CCC+ predicted good functional outcomes (mRS 0-2: OR=20.8 [95% CI 9.3-46.8]; p<0.001) compared to CCC- and CCCmixed. CCCmixed (β: 27.1, SE: 7.7; p<0.001) and CCC- (β: 86.6, SE: 9.9; p<0.001) profiles were associated with higher final infarct volumes after treatment compared to CCC+. Conclusion: Comprehensive assessment of the collateral blood flow cascade in AIS-LVO patients is a strong predictor of clinical and radiological outcomes in AIS-LVO patients.

scholarly journals Effect of Oxygen Extraction (Brush-Sign) on Baseline Core Infarct Depends on Collaterals (HIR)

2021 ◽  
Vol 11 ◽  
Author(s):  
Adrien Guenego ◽  
Matthew Leipzig ◽  
Robert Fahed ◽  
Eric S. Sussman ◽  
Tobias D. Faizy ◽  
...  
Keyword(s):  
Blood Flow ◽  
Ischemic Stroke ◽  
Infarct Volume ◽  
Critical Factor ◽  
Oxygen Extraction ◽  
Collateral Blood Flow ◽  
Small Baseline ◽  
Cerebral Ischemic ◽  
Effect Of Oxygen ◽  
Core Infarct

Objectives: Baseline-core-infarct volume is a critical factor in patient selection and outcome in acute ischemic stroke (AIS) before mechanical thrombectomy (MT). We determined whether oxygen extraction efficiency and arterial collaterals, two different physiologic components of the cerebral ischemic cascade, interacted to modulate baseline-core-infarct volume in patients with AIS-LVO undergoing MT triage.Methods: Between January 2015 and March 2018, consecutive patients with an AIS and M1 occlusion considered for MT with a baseline MRI and perfusion-imaging were included. Variables such as baseline-core-infarct volume [mL], arterial collaterals (HIR: TMax &gt; 10 s volume/TMax &gt; 6 s), high oxygen extraction (HOE, presence of the brush-sign on T2*) were assessed. A linear-regression was used to test the interaction of HOE and HIR with baseline-core-infarct volume, after including potential confounding variables.Results: We included 103 patients. Median age was 70 (58–78), and 63% were female. Median baseline-core-infarct volume was 32 ml (IQR 8–74.5). Seventy six patients (74%) had HOE. In a multivariate analysis both favorable HIR collaterals (p = 0.02) and HOE (p = 0.038) were associated with lower baseline-core-infarct volume. However, HOE significantly interacted with HIR (p = 0.01) to predict baseline-core-infarct volume, favorable collaterals (low HIR) with HOE was associated with small baseline-core-infarct whereas patients with poor collaterals (high HIR) and HOE had large baseline-core-infarct.Conclusion: While HOE under effective collateral blood-flow has the lowest baseline-core-infarct volume of all patients, the protective effect of HOE reverses under poor collateral blood-flow and may be a maladaptive response to ischemic stroke as measured by core infarctions in AIS-LVO patients undergoing MT triage.

Abstract WP47: Reperfusion Following Ischemic Stroke is Associated with Reduced Brain Edema

Stroke ◽  
2017 ◽  
Vol 48 (suppl_1) ◽  
Author(s):  
Hannah J Irvine ◽  
Thomas W Battey ◽  
Ann-Christin Ostwaldt ◽  
Bruce C Campbell ◽  
Stephen M Davis ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Brain Edema ◽  
Infarct Volume ◽  
Brain Magnetic Resonance Imaging ◽  
Lesion Volume ◽  
Stroke Patients ◽  
Early Reperfusion ◽  
Echoplanar Imaging ◽  
Swelling Volume

Introduction: Revascularization is a robust therapy for acute ischemic stroke, but animal studies suggest that reperfusion edema may attenuate its beneficial effects. In stroke patients, early reperfusion consistently reduces infarct volume and improves long-term functional outcome, but there is little clinical data available regarding reperfusion edema. We sought to elucidate the relationship between reperfusion and brain edema in a patient cohort of moderate to severe stroke. Methods: Seventy-one patients enrolled in the Echoplanar Imaging Thrombolysis Evaluation Trial (EPITHET) with serial brain magnetic resonance imaging and perfusion-weighted imaging (PWI) were analyzed. Reperfusion percentage was calculated based on the difference in PWI lesion volume at baseline and follow-up (day 3-5). Midline shift (MLS) was measured on the day 3-5 fluid attenuated inversion recovery (FLAIR) sequence. Swelling volume and infarct growth volume were assessed using region-of-interest analysis on the baseline and follow-up DWI scans based on our prior methods. Results: Greater percentage of reperfusion was associated with less MLS (Spearman ρ = -0.46; P <0.0001) and reduced swelling volume (Spearman ρ = -0.56; P <0.0001). In multivariate analysis, reperfusion was an independent predictor of less MLS ( P <0.006) and decreased swelling volume ( P <0.0054), after adjusting for age, baseline NIHSS, admission blood glucose, baseline DWI volume, and IV tPA treatment. Conclusions: Reperfusion is associated with reduced brain edema as measured by MLS and swelling volume. While our data do not exclude the possibility of reperfusion edema in certain circumstances, in stroke patients, reperfusion following acute stroke is predominantly linked to less brain swelling.

Abstract P538: A Detailed Analysis of Intracranial Hemorrhage After Endovascular Treatment in Acute Ischemic Stroke Due to Large Vessel Occlusion in the Escape-NA1 Trial

Stroke ◽  
2021 ◽  
Vol 52 (Suppl_1) ◽  
Author(s):  
Johanna Ospel ◽  
Michael D Hill ◽  
Nima Kashani ◽  
Arnuv Mayank ◽  
Nishita Singh ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Acute Ischemic Stroke ◽  
Intracranial Hemorrhage ◽  
Intraventricular Hemorrhage ◽  
Infarct Volume ◽  
Prognostic Impact ◽  
Vessel Occlusion ◽  
Good Outcome

Purpose: We investigated the prevalence and prognostic impact on outcome of any intracranial hemorrhage, hemorrhage morphology, type and volume in acute ischemic stroke patients undergoing mechanical thrombectomy. Methods: Prevalence of intracranial hemorrhage, hemorrhage type, morphology and volume was determined on 24h follow-up imaging (non contrast head CT or gradient-echo/susceptibility-weighted MRI). Proportions of good outcome (mRS 0-2 at 90 days) were reported for patients with vs. without any intracranial hemorrhage. Multivariable logistic regression with adjustment for key minimization variables and total infarct volume was performed to obtain adjusted effect size estimates for hemorrhage type and volume on good outcome. Results: Hemorrhage on follow up-imaging was seen in 372/1097 (33.9%) patients, among them 126 (33.9%) with hemorrhagic infarction (HI) type 1, 108 (29.0%) with HI-2, 72 /19.4%) with parenchymal hematoma (PH) type 1, 37 (10.0) with PH2, 8 (2.2%) with remote PH and 21 (5.7%) with extra-parenchymal/intraventricular hemorrhage. Good outcomes were less often achieved by patients with hemorrhage on follow-up imaging (164/369 [44.4%] vs. 500/720 [69.4%]). Any type of intracranial hemorrhage was strongly associated with decreased chances of good outcome ( adj OR 0.62 [CI 95 0.44 - 0.87]). The effect of hemorrhage was driven by both PH hemorrhage sub-type [PH-1 ( adj OR 0.39 [CI 95 0.21 - 0.72]), PH-2 ( adj OR 0.15 [CI 95 0.05 - 0.50])] and extra-parenchymal/intraventricular hemorrhage ( adj OR 0.60 (0.20-1.78) Petechial hemorrhages (HI-1 and HI-2) were not associated with poorer outcomes. Hemorrhage volume ( adj OR 0.97 [CI 95 0.05 - 0.99] per ml increase) was significantly associated with decreased chances of good outcome. Conclusion: Presence of any hemorrhage on follow-up imaging was seen in one third of patients and strongly associated with decreased chances of good outcome.

Abstract 3681: Early Anticoagulation Is Not Associated With Hemorrhagic Transformation Of Ischemic Stroke In Patients With Atrial Fibrillation

Stroke ◽  
2012 ◽  
Vol 43 (suppl_1) ◽  
Author(s):  
H. B Brouwers ◽  
Svetlana Lorenzano ◽  
Lyndsey H Starks ◽  
David M Greer ◽  
Steven K Feske ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Ischemic Stroke ◽  
Acute Ischemic Stroke ◽  
Clinical Data ◽  
Infarct Volume ◽  
Hemorrhagic Transformation ◽  
P Value ◽  
Long Term Outcome ◽  
Nihss Score

Purpose: Hemorrhagic transformation (HT) is a common and potentially devastating complication of ischemic stroke, however its prevalence, predictors, and outcome remain unclear. Early anticoagulation is thought to be a risk factor for HT which raises the clinical question when to (re)start anticoagulation in ischemic stroke patients who have a compelling indication, such as atrial fibrillation. We conducted a prospective cohort study to address this question and to identify association of hemorrhagic transformation with outcome measures in patients with atrial fibrillation in the setting of acute ischemic stroke. Materials and Methods: We performed a prospective study which enrolled consecutive patients admitted with acute ischemic stroke presenting to a single center over a three-year period. As part of the observational study, baseline clinical data and stroke characteristics as well as 3 month functional outcome were collected. For this sub-study, we restricted the analysis to subjects diagnosed with atrial fibrillation. CT and MRI scans were reviewed by experienced readers, blinded to clinical data, to assess for hemorrhagic transformation (using ECASS 2 criteria), microbleeds and infarct volumes in both admission and follow-up scans. Clinical and outcome data were analyzed for association with hemorrhagic transformation. Results: Of 94 patients, 63 had a history of atrial fibrillation (67.0%) and 31 had newly discovered atrial fibrillation (33.0%). We identified HT in 3 of 94 baseline scans (3.2%) and 22 of 48 follow-up scans (45.8%) obtained a median of 3 days post-stroke. In-hospital initiation of either anti-platelet (n = 36; OR 0.34 [95% CI 0.10-1.16], p-value = 0.09) or anticoagulation with unfractionated intravenous heparin or low molecular weight heparin (n = 72; OR 0.25 [95% CI 0.06-1.15], p-value = 0.08) was not associated with HT. Initial NIH Stroke Scale (NIHSS) score (median 13.0 [IQR 15.0] vs. 7.0 [IQR 10.0], p-value = 0.029) and baseline infarct volume (median 17 [IQR 42.03] vs. 5 [IQR 10.95], p-value = 0.011) were significantly higher in patients with HT compared to those without. Hemorrhagic transformation was associated with a significantly higher 48-hour median NIHSS score (20 [IQR 3.0] vs. 2 [IQR 3.25], p-value = 0.007) and larger final infarct volume (81.40 [IQR 82.75] vs. 9.95 [IQR 19.73], p-value < 0.001). Finally, we found a trend towards poorer 3-month modified Rankin Scale scores in subjects with HT (OR 11.25 [95% CI 0.97-130.22], p-value = 0.05). Conclusion: In patients with atrial fibrillation, initial NIHSS score and baseline infarct volume are associated with hemorrhagic transformation in acute ischemic stroke. Early initiation of antithrombotic therapy was not associated with hemorrhagic transformation. Patients with hemorrhagic transformation were found to have a poorer short and long term outcome and larger final infarct volumes.

Diffusion imaging of cerebral diaschisis in childhood arterial ischemic stroke

2016 ◽  
Vol 11 (9) ◽  
pp. 1028-1035 ◽  
Author(s):  
Adam Kirton ◽  
Elizabeth Williams ◽  
Michael Dowling ◽  
Sarah Mah ◽  
Jacquie Hodge ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Ischemic Stroke ◽  
Magnetic Resonance ◽  
Diffusion Weighted Imaging ◽  
Infarct Volume ◽  
Resonance Imaging ◽  
Arterial Ischemic Stroke ◽  
Diffusion Weighted ◽  
Motor Outcome

Background Diffusion-weighted imaging magnetic resonance imaging may detect changes in brain structures remote but connected to stroke consistent with neuropathological descriptions of diaschisis. Early diffusion-weighted imaging demonstrates restriction in corticospinal pathways after arterial ischemic stroke of all ages that correlates with motor outcome. Aim/hypothesis We hypothesized that cerebral diaschisis is measurable in childhood arterial ischemic stroke and explored associations with outcome. Methods This sub-study of the validation of the Pediatric NIH Stroke Scale study prospectively enrolled children with acute arterial ischemic stroke and both acute and early follow-up (5–14 days) diffusion-weighted imaging. Inclusion criteria were (1) unilateral middle cerebral artery arterial ischemic stroke, (2) acute and subacute diffusion-weighted imaging ( b = 1000), and (3) 12 month neurological follow-up (Pediatric Stroke Outcome Measure). A validated method using ImageJ software quantified diffusion-weighted imaging diaschisis in anatomically connected structures. Diaschisis measures were corrected for infarct volume, compared to age, imaging timing, and outcomes (Chi square/Fisher, Mann–Whitney test). Results Nineteen children (53% male, median 8.1 years) had magnetic resonance imaging at medians of 21 and 168 h post-stroke onset. Diaschisis was common and evolved over time, observed in one (5%) on acute but eight (42%) by follow-up diffusion-weighted imaging. Thalamic and callosal diaschisis were most common (5, 26%). Estimates of perilesional diaschisis varied (54 ± 18% of infarct volume). Children with diaschisis tended to be younger (7.02 ± 5.4 vs. 11.82 ± 4.3 years, p = 0.08). Total diaschisis score was associated with poor cognitive outcomes ( p = 0.03). Corticospinal tract diaschisis was associated with motor outcome ( p = 0.004). Method reliability was excellent. Conclusions Diffusion-weighted imaging diaschisis occurs in childhood arterial ischemic stroke. Mistaking diaschisis for new areas of infarction carries important clinical implications. Improved recognition and study are required to establish clinical relevance.

Abstract 1122‐000181: Collateral Circulation in Ischemic Stroke is Not Determined by Anatomical Variants of the Cerebral Arteries

2021 ◽  
Vol 1 (S1) ◽  
Author(s):  
Karolina Brzegowy ◽  
Bernard Solewski ◽  
Paweł Brzegowy ◽  
Agata Musiał ◽  
Tadeusz Popiela ◽  
...  
Keyword(s):  
Blood Flow ◽  
Ischemic Stroke ◽  
Collateral Circulation ◽  
Cerebral Arteries ◽  
Anatomical Variations ◽  
Detailed Knowledge ◽  
Collateral Blood Flow ◽  
Posterior Portion ◽  
Cortical Vein ◽  
Anatomical Variants

Introduction : In acute ischemic stroke, collateral circulation determines tissue fate and treatment results. The aim of this study was to evaluate the role of anatomical variations of the Circle of Willis (CoW) in formation of cerebral collateral blood flow in patients with acute M1 occlusion. Methods : This study was a retrospective assessment of radiological examinations of patients with stroke due to middle cerebral artery M1 segment occlusion. All patients underwent mechanical thrombectomy from January 2015 until March 2021. The anatomy of the CoW was assessed on initial CT‐angiography and DSA. CTA was utilized to grade cranial collateral vasculature status and cortical vein opacification score (COVES). Non‐contrast CT scans and ASPECTS scores (using RAPID software) were used to determine the ischemic area. Results : A total of 100 patients were included in the analysis (58 females and 42 males, mean age: 71.6 +/‐ 13.9). We classified the anatomy of the CoW according to its continuity as a full circle. Patients with fully continuous CoW (n = 19) had worse COVES scores than those with CoW incomplete at both anterior and posterior portion (n = 9) (89% vs 68% with COVES 0–2, p = 0.179). No statistically significant results were found when comparing the enhancement of collaterals between these two groups (p = 0.390). The COVES scores were similar for patients with complete and incomplete anterior portions of CoW (77% vs 80% with COVES 0–2, p = 0.812). Patients with incomplete posterior portions of CoW had lower COVES scores than those with complete (80% vs 67% with COVES 0–2, p = 0.206). No statistically significant differences were discovered when comparing different types of the posterior communicating artery (adult, transitional and fetal). Analysis of ischemic areas determined as ASPECTS scores pre‐ and post‐thrombectomy yielded no significant differences between any of the groups. Conclusions : Although certain variants of the CoW have been reported to increase the risk of ischemic stroke, our results show that the anatomy of CoW has no large effect on collateral blood flow during acute M1 occlusion. We presume that the greater role is played by pial arterioles than anatomical variants of major cerebral arteries in cerebral collateral circulation formation. Detailed knowledge about the factors that influence collateral blood flow is crucial as it may aid in identification of patients prone to worse outcomes of ischemic stroke. Anatomical variants of CoW do not play a major role in formation of cerebral collaterals.

The Safety and Feasibility of Mechanical Thrombectomy for Mild Acute Ischemic Stroke With Large Vessel Occlusion

Neurosurgery ◽  
2019 ◽  
Vol 86 (6) ◽  
pp. 802-807 ◽  
Author(s):  
Gabor Toth ◽  
Santiago Ortega-Gutierrez ◽  
Jenny P Tsai ◽  
Russell Cerejo ◽  
Sami Al Kasab ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Mechanical Thrombectomy ◽  
Infarct Volume ◽  
Invasive Procedure ◽  
Large Vessel ◽  
Large Vessel Occlusion ◽  
Vessel Occlusion ◽  
Symptomatic Intracerebral Hemorrhage ◽  
Significant Difference

Abstract BACKGROUND Prospective evidence to support mechanical thrombectomy (MT) for mild ischemic stroke with large vessel occlusion (LVO) is lacking. There is uncertainty about using an invasive procedure in patients with mild symptoms. OBJECTIVE To evaluate the safety and feasibility of MT in patients with mild symptoms and LVO. METHODS Our single-arm prospective pilot study recruited patients with LVO and initial National Institute of Health Stroke Scale (NIHSS) &lt;6, who underwent standard MT. Primary safety endpoints were symptomatic intracerebral hemorrhage (sICH), and/or worsening NIHSS by ≥4 points. Secondary endpoints included angiographic recanalization, NIHSS change, final infarct volume, and modified Rankin score (mRS). RESULTS We enrolled 20 patients (mean age 65.6 ± 12.3 yr; 45% females). Thrombolysis in Cerebral Ischemia 2B/3 thrombectomy was achieved in 95%. No patients suffered sICH. One patient (5%) had neurologic worsening within 24 h because of underlying intracranial stenosis. No other complications or safety concerns were identified. Median NIHSS was significantly better at discharge (0.5, P = .007) and at last follow-up (0, P &lt; .001) than before treatment (3). Mean post vs preintervention infarct volumes were small without significant difference (1.2 ml, P = .434). Most patients (85%) were discharged directly home. Excellent clinical outcome (mRS 0-1) at last follow-up was seen in 95% of patients. CONCLUSION This is one of the first specifically designed prospective studies showing that MT is safe and feasible in patients with low NIHSS and LVO. Chronic underlying vasculopathy may be a challenging dilemma. We observed excellent clinical and radiographic outcomes, but randomized controlled trials are needed to demonstrate the efficacy of MT in this unique cohort.

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