Comparison of Arterial Spin Labeling and Bolus Perfusion-Weighted Imaging for Detecting Mismatch in Acute Stroke

Background: and Purpose: The aim of this study was to investigate whether pseudo-continuous arterial spin-labeling (ASL) in combination with an appropriate cerebral blood flow (CBF) threshold can reliably detect tissue at-risk for infarction. Methods: The retrospective study included 50 patients with acute stroke in the middle cerebral artery (MCA) territory who underwent perfusion-weighted magnetic resonance imaging (PW-MRI) within 24 hr of symptom onset and again in the subacute phase. After image co-registration the core and mismatch were segmented on ASL maps. Receiver operating characteristic (ROC) curve analysis was performed to calculate the optimal ASL-CBF threshold. Volumes on PW-MRI were recorded based on their ASL-CBF threshold (≧19-, 20-, 21-, 22-, 23-, 24- and 25 sec). Then the correlation between the penumbral salvage area and infarct growth, defined as the size difference between the lesion on baseline PWI- and the baseline diffusion-weighted images, and the final infarct volume were determined. Results: ROC analysis showed that the optimal threshold was 21.2 mL/100 g/min (area under the curve 0.88). The correlation between infarct growth and the penumbra salvage volume was significantly better for PWI lesions defined by ASL≦21 mL/100 g/min (r=-0.66; p<0.001). In 9 patients without recanalization on MRI obtained in the subacute phase, the ASL≦21 mL/100 g/min threshold more closely predicted the final infarct volume (r=0.82; p=0.006). Conclusion: PWI (ASL≧21 ml/100 g/min) volumes may provide an approximation of the volume of tissue at-risk for infarction in patients with acute stroke in the MCA territory.

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Abstract W MP114: Arterial Spin Label Perfusion Imaging in Acute Neonatal Stroke Reveals Hyperperfusion in Association With Cerebral Ischemic Injury

Stroke ◽

10.1161/str.45.suppl_1.wmp114 ◽

2014 ◽

Vol 45 (suppl_1) ◽

Author(s):

Michael J Rivkin ◽

Christopher G Watson ◽

Mathieu Dehaes ◽

Borjan A Gagoski ◽

P. E Grant

Keyword(s):

Acute Stroke ◽

Arterial Spin Labeling ◽

Ischemic Injury ◽

Spin Labeling ◽

Arterial Spin Label ◽

Regional Perfusion ◽

Perfusion Magnetic Resonance Imaging ◽

Arterial Ischemic Stroke ◽

Neonatal Stroke ◽

Scan Time

Introduction: Perfusion magnetic resonance imaging (pMRI) in adults reveals a hypoperfused region, the ischemic penumbra, related to the fixed ischemic injury shown by diffusion weighted imaging (DWI) in acute stroke. Neonatal stroke has pathophysiology and optimum treatment that remain elusive. We hypothesized that altered regional perfusion accompanies the ischemic injury in focal neonatal stroke. Methods: Neonates (0-28 days of life) underwent MR imaging at 3T fieldstrength. pMRI employed a pseudocontinuous arterial spin labeling (PCASL) sequence with multi-slice echo planar readouts at 3x3x5mm3 resolution with TE/TR = 12ms/3.5s, labeling time = 1.6s, a post-labeling delay = 1.5s, 9 axial slices acquired, scan time ~5 min. Forty label/control image pairs were acquired, subtracted and averaged to obtain contrast maps proportional to quantified cerebral blood flow (CBF). DWI, susceptibility weighted imaging and T2-weighted series were obtained with standard protocols. Acute stroke was classified as arterial or venous. Core infarction was considered to lie in hypointense regions on DWI apparent diffusion coefficient maps. Regional perfusion signal was compared to the ischemic core on DWI and to the homologous uninvolved region in the contralesional hemisphere. Results: Data were collected on 20 neonates, (13 males; median/mean gestational age=38/38.5 weeks) with acute stroke (11 arterial ischemic stroke (AIS); 9 venous) scanned at median postnatal age=1.5 days. Evidence of regional hyperperfusion existed in 10/11 (91%) neonates with AIS and 4/9 (44%) with venous stroke. Hyperperfusion was part of a heterogeneous pattern of hypo- and hyperperfusion in 4 infants with AIS and 3 infants with venous infarct. Electroencephalography data obtained at presentation were available for 19 (95%) of the neonates. Fourteen infants (70%) had either electrographic seizure or focal sharp waves in the same hemisphere as the acute infarction. Conclusion: Arterial spin labeling pMRI can be successfully obtained in acute neonatal stroke. Unlike adults, pMRI often reveals hyperperfusion rather than hypoperfusion in neonates. This hyperperfusion may be due to early spontaneous reperfusion or to the neuronal hyperexcitability of stroke-associated seizure.

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Arterial Spin Labeling—Can Neurointerventionists Rely on This Novel Technique? A Case Series on Successful Use of Arterial Spin Labeling in Acute Stroke Imaging

Journal of Clinical Interventional Radiology ISVIR ◽

10.1055/s-0037-1603829 ◽

2017 ◽

Vol 01 (03) ◽

pp. 144-149

Author(s):

K. Rahul ◽

P. Santhosh ◽

M. Kumar ◽

Pankaj Mehta ◽

Mathew Cherian

Keyword(s):

Acute Stroke ◽

Arterial Spin Labeling ◽

Mechanical Thrombectomy ◽

Case Series ◽

Spin Labeling ◽

Ischemic Penumbra ◽

Anterior Circulation ◽

Vessel Occlusion ◽

Stroke Imaging ◽

Noninvasive Imaging Technique

AbstractPresence of ischemic penumbra is the principal factor that decides the need for mechanical thrombectomy in acute stroke patients with large vessel occlusion. Our objective was to evaluate the usefulness of arterial spin labeling (ASL) in detecting diffusion perfusion mismatch and directing patients into mechanical thrombectomy. We retrospectively studied all patients with acute nonhemorrhagic stroke in the anterior circulation, who had undergone stroke imaging with ASL followed by mechanical thrombectomy from July 2016 to November 2016. Area of diffusion perfusion mismatch was graded semiquantitatively into three grades: small, medium, and large. Mismatch was compared with 30-day modified Rankin scale (mRS) score. Interpretable PASL-perfusion images were obtained in all patients. Diffusion perfusion mismatches were present in all patients. Out of six patients with good mRS score, five patients had large diffusion perfusion mismatch. Two out of three patients with poor mRS were secondary to failed recanalization, in spite of large mismatch. One out of nine patients had poor outcome as well as a small area of mismatch. ASL is a rapid noninvasive imaging technique in acute stroke that has got the potential to detect ischemic penumbra.

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Abstract WMP15: Hyperperfusion on Arterial Spin Labeling: Objective Decision Support Using Pattern Recognition

Stroke ◽

10.1161/str.47.suppl_1.wmp15 ◽

2016 ◽

Vol 47 (suppl_1) ◽

Author(s):

Fabien Scalzo ◽

Songlin Yu ◽

Sagar Patel ◽

David Liebeskind ◽

Danny Wang

Keyword(s):

Pattern Recognition ◽

Blood Flow ◽

Cerebral Blood Flow ◽

Decision Support ◽

Acute Stroke ◽

Arterial Spin Labeling ◽

Objective Measure ◽

Spin Labeling ◽

Hemorrhagic Transformation ◽

Stroke Patients

Background: Hyperperfusion detected on arterial spin labeling (ASL) images acquired after stroke onset has been shown to correlate with subsequent hemorrhagic transformation (HT). Presence of hyperperfusion is typically detected by visual review of arterial spin labeling cerebral blood flow (CBF). Such a review is subjective as it is challenged by inter-reader variability, noise, and lack of standard threshold. We present in this study a quantitative hyperperfusion detection model that can provide an objective decision support for the interpretation of ASL CBF maps and rapidly delineate hyperperfusion regions. Methods: ASL Cerebral blood flow (CBF) maps of acute stroke patients presenting with an occlusion in the MCA territory were coregistered to a standardized atlas space. To achieve reliable detection of ASL hyperperfusion, we formalize the problem as a nonlinear classification that relates regional voxel intensity values to the corresponding binary label (normal or hyperperfused). Our method takes into account the healthy contralateral hemisphere and its CBF intensity values during the determination of hyperperfusion of a voxel. Each input feature vector combines the regional intensity values at the voxel of interest, its contralateral matched region, and the distribution of the difference between them. Each input vector is associated to a label corresponding to the presence of hyperperfusion that was manually established by consensus between experts. The predicted hyperperfusion regions were compared to a groundtruth that manually established by two researchers. Results: A total of 361 ASL scans were collected from 221 patients (age=72±17 years; 45% males). Hyperperfusion was detected in 76 patients that were subsequently used in our analysis. An AUC of 83±5% was reached after a leave-one-out cross-validation, which corresponds to the accuracy in detecting hyperperfusion compared to manual delineation of hyperperfusion on ASL CBF maps. Conclusion: Pattern recognition based on a nonlinear regression can provide an accurate and objective measure of hyperperfusion on ASL CBF images and could therefore improve the detection of hemorrhagic transformation in acute stroke patients.

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Arterial Spin Labeling Imaging Findings in Transient Ischemic Attack Patients: Comparison with Diffusion- and Bolus Perfusion-Weighted Imaging

Cerebrovascular Diseases ◽

10.1159/000339682 ◽

2012 ◽

Vol 34 (3) ◽

pp. 221-228 ◽

Cited By ~ 28

Author(s):

Greg Zaharchuk ◽

Jean-Marc Olivot ◽

Nancy J. Fischbein ◽

Roland Bammer ◽

Matus Straka ◽

...

Keyword(s):

Transient Ischemic Attack ◽

Arterial Spin Labeling ◽

Spin Labeling ◽

Imaging Findings ◽

Perfusion Weighted Imaging ◽

Ischemic Attack

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Quantification of Serial Cerebral Blood Flow in Acute Stroke Using Arterial Spin Labeling

Stroke ◽

10.1161/strokeaha.116.014707 ◽

2017 ◽

Vol 48 (1) ◽

pp. 123-130 ◽

Cited By ~ 18

Author(s):

George W.J. Harston ◽

Thomas W. Okell ◽

Fintan Sheerin ◽

Ursula Schulz ◽

Phil Mathieson ◽

...

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Acute Stroke ◽

Arterial Spin Labeling ◽

Spin Labeling

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Whole-Brain Arterial Spin Labeling Perfusion MRI in Patients With Acute Stroke

Stroke ◽

10.1161/strokeaha.110.589234 ◽

2012 ◽

Vol 43 (5) ◽

pp. 1290-1294 ◽

Cited By ~ 71

Author(s):

Reinoud P.H. Bokkers ◽

Daymara A. Hernandez ◽

José G. Merino ◽

Raymond V. Mirasol ◽

Matthias J. van Osch ◽

...

Keyword(s):

Acute Stroke ◽

Arterial Spin Labeling ◽

Spin Labeling ◽

Perfusion Mri ◽

Whole Brain

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Measurement of collateral perfusion in acute stroke: a vessel-encoded arterial spin labeling study

Scientific Reports ◽

10.1038/s41598-019-44417-7 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 1

Author(s):

Thomas W. Okell ◽

George W. J. Harston ◽

Michael A. Chappell ◽

Fintan Sheerin ◽

James Kennedy ◽

...

Keyword(s):

Acute Stroke ◽

Arterial Spin Labeling ◽

Spin Labeling

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