Comparison Between TOF and SWAN Sequences in the Detection of Arterial Occlusion in Acute Ischemic Stroke Using MRI

Study Overview
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Brief Summary
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Optimizing the MRI protocol in acute ischemic stroke remains a challenging issue. In this field, susceptibility-weighted sequences have proved their superiority over T2. Besides the strengthened susceptibility effect, enhanced susceptibility-weighted angiography (eSWAN) sequence provides also a time-of-flight (TOF) effect, allowing the exploration of the intracranial arterial circulation. The objective of this study is to compare eSWAN and 3D TOF, considered as the reference, in the detection of arterial occlusion in acute stroke.

Detailed Description
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Patients who undergo MRI for suspected acute stroke with an acute ischemic lesion on diffusion-weighted imaging (DWI) will be prospectively included in this study.eSWAN and TOF images will be analyzed under double-blind conditions by a junior radiologist and a senior neuroradiologist for the detection of arterial occlusion. eSWAN images will be assessed in order to estimate the inter-observer agreement. After a consensus, eSWAN and TOF data will be compared to calculate inter-modality agreement.

Official Title
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Comparison Between Enhanced Susceptibility-weighted Angiography and Time of Flight Sequences in the Detection of Arterial Occlusion in Acute Ischemic Stroke Using MRI

Conditions
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Angiography, Stroke, Acute, Magnetic Resonance Imaging, Diagnosis

Intervention / Treatment
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* Diagnostic Test: Magnetic resonance imaging


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: clinical symptoms compatible with acute stroke; time range between symptoms and magnetic resonance imaging less than 4 h 30 presence of at least one acute ischemic lesion on the diffusion-weighted images (DWI). Exclusion Criteria: MR contraindications; negative DWI; differential diagnosis; incomplete acquisition of the full magnetic resonance imaging protocol or technical issues leading to uninterpretable eSWAN and/or TOF sequences (e.g.motion artifacts).

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 |
| --- | --- |
| Acute stroke patients<br>MRI examinations will be performed on a 3 T GE MR750 W scanner. Two readers, an experienced neuroradiologist (8 years of experience in neuroradiology) and a junior radiologist (3 years of experience in general radiology) will independently analyze eSWAN and TOF images in random order, looking for arterial occlusions. Analysis will be based on a 2-point-scale: arterial occlusion, based on a local signal loss, or acceptable permeability. | Diagnostic Test: Magnetic resonance imaging<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Concordance of observed agreement using eSWAN and TOF images measured by Cohen's kappa coefficient | Concordance of observed agreement for the detection of arterial occlusion between eSWAN and TOF images | at inclusion | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Concordance inter-observer agreement for the detection of arterial occlusion using eSWAN images measured by Cohen's kappa coefficient | Concordance inter-observer agreement between the two readers for the detection of arterial occlusion using eSWAN images | at inclusion | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Acute stroke, Susceptibility-weighted imaging, Arterial occlusion, Time of flight