Multi-delay Arterial Spin Labeling Application in Acute Ischemic Stroke

Study Overview
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Brief Summary
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This study explores the value of the non-invasive quantitative evaluation system for cerebral blood flow perfusion function in the diagnosis of stroke. Compared with traditional perfusion techniques, multi-delay arterial spin labeling (ASL) is validated to determine the accuracy of perfusion level, ischemic penumbra and other indexes in patients with acute ischemic stroke. The relationship between perfusion levels of mD-ASL parameters and clinical outcome is also studied.

Detailed Description
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A total of 200 patients with acute anterior circulation ischemic stroke will be prospectively enrolled. All patients underwent CTP, multi-delay ASL, DWI, CTA or TOF-MRA scanning. CBF, CBV, MTT and Tmax will be obtained based on CTP, and the range of reversible cerebral ischemia injury will be calculated based on DWI and CTP data. CBF, CBV and ATT images will be obtained based on the multi-delay ASL, and the calculated results of reversible cerebral ischemia injury will also be obtained. Meanwhile, the image quality of CTP and multi-delay ASL will be evaluated. The time from the patient to the completion of imaging examination and the imaging examination time will be recorded. Mann-whitney U test and T test can be used to compare the difference of assessment time between different test methods. Chi-square test can be used to compare the differences of image quality among different examination methods. Wilcoxon rank sum test can be used to evaluate the difference between CTP and Multi-delay ASL in terms of parameters and volume of reversible ischemic injury.

Official Title
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Application of a Noninvasive Quantitative Assessment System for Cerebral Perfusion Function in the Green Channel of Acute Stroke

Conditions
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Stroke

Intervention / Treatment
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* Diagnostic Test: multi-delay arterial spin labeling


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Ischemic stroke within 24h； Anterior circulation occlusion confirmed by conventional angiography or magnetic resonance angiography； Exclusion Criteria: Pregnancy and other contraindication to MRI scan； Informed consent not obtained.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| ischemic stroke<br>The cohort includes patients with acute stroke who underwent CTP, multi-delay ASL, DWI, CTA or TOF-MRA scanning.All patients will be examined within 24 hours of onset. CBF, CBV, MTT and Tmax cerebral blood flow parameter images of CTP will be obtained. CBF, CBV and ATT cerebral blood flow parameter images in multi-delay ASL will be obtained by the quantitative evaluation system. The volume of reversible ischemic tissue will be calculate according to CTP and multi-delay ASL respectively. | Diagnostic Test: multi-delay arterial spin labeling<br>* Multi-delay arterial spin labeling is a new method to evaluate the degree of the cerebral perfusion. It can obtain three parameters including CBF,CBV and ATT without radiation,which is similar to the traditional technology. Multi-delay ASL can provide more information of the acute stroke patients.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Compare the volume of reversible ischemic injury of brain tissue measured by multi-delay ASL versus CTP | Our primary aim is to determine if the diagnostic accuracy of multi-delay Arterial Spin Labeling (ASL) is as good as the diagnostic accuracy of CTP in acute ischemic stroke patient. To test if ASL in noninferior to CTP, | 24 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The difference of the procedure of CTP and multi-delay ASL | The researchers will collect the time from diagnosis to completion of imaging examination and the time of imaging examination.Then analyze the time and quality of the multi-delay ASL compared with CTP. | 24hours | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Ischemic Stroke, Magnetic Resonance Imaging, Cerebrovascular Disease