Classification of Carotid Plaque With Computed Tomography With Fast kVp (Kilovolt Peak)-Switching Technique

Study Overview
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Brief Summary
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Classification of carotid plaque vessel wall changes in carotid stenosis accordingly to AHA classification (American Heart Association)- comparison between histology and CT. The CT is performed with a fast kVp-switching dual energy technique. To compare the ability to detect iodine contrast enhancement in the carotid plaque compared with 3T MRI with gadolinium.

Detailed Description
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Patients planned for CEA (carotid endarterectomy) due to carotid stenosis will be examined with one extra CT and MRI before surgery. The CEA specimen is stored in the BiKE-registry (a biobank of operated carotid plaque at the Karolinska Institute). In that registry the patients will be given a personal code which is used to identify the CT, MRI and histology data further on. Approved by regional ethical review board in Stockholm and local radiation comity at Karolinska University Hospital Solna (Dnr K2435-2014). Informed consent from the participating patients.

Official Title
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Classification of Carotid Plaque With Computed Tomography With Fast kVp-switching Technique: A Comparison With Histology and 3-Tesla MRI

Conditions
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Atherosclerosis, Carotid Stenosis

Intervention / Treatment
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* Other: Carotid endarterectomy in clinical healthcare.


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 50% stenosis (NASCET) or more based on CTA (CT-angiography), MRI or US, Scheduled for CEA 50 years or older, Normal kidney function (estimated GFR (glomerular filtration rate) 60 ml/min or more). Exclusion Criteria: Contraindications to iodine contrast media, Contraindications to MRI or gadolinium contrast media.

Ages Eligible for Study
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Minimum Age: 50 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

| Intervention/Treatment |
| --- |
|Other: Carotid endarterectomy in clinical healthcare.|For the this study itself there is no intervention caused by the extra CT or MRI. The patients are scheduled for surgery as the routine intervention to reduce the risk of a new stroke in clinical practice. The performed extra diagnostic CT and MRI in this study before surgery will compare the vessel wall images with histology regardless of the patients status or medication.|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Classification of the carotid plaque accordingly to AHA classification: Fast kVp-switching dual energy CT with histology | The time between radiological examination, surgery and histological analysis is usually approximately 4 weeks | 4 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Comparison between the ability to detect contrast enhancement in the carotid plaque: Fast kVp-switching CT vs 3T MRI | The time between fast kVp-switching CT and MRI examinations and reporting is usually approximately 1week. | 1 week |