Advanced Ultrasound Methods in the Assessment of Carotid Plaque Instability

Study Overview
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Brief Summary
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The primary aim of this project is to assess if advanced ultrasound methods such as SMI (Superb microvascular Imaging) and SWE (Shear Wave Elastography) can identify intraplaque neovascularization and plaque tissue stiffness in carotid artery plaques and relate these results to ipsilateral cerebrovascular symptoms. The secondary aim of this project is to assess the level of agreement between the structural plaque characteristics assessed by advanced ultrasound examinations such as SMI, SWE, CEUS (Contrast enhanced ultrasound), GSM (Plaque gray-scale-median) and carotid MRI, metabolic activity of plaque assessed by 18F-FDG PET/CT with histology as the gold standard. Findings from the methods mentioned above will be related to cerebrovascular symptoms, blood tests (cholesterol-tot, LDL, HDL, CRP, leukocytes, glucose, HbA1c) and other cardiovascular risk factors at inclusion and upon 1 year follow up.

Detailed Description
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The project will include 3 studies: Study 1: Analyse the correlation between SMI assessed neovascularization and degree of stenosis in symptomatic patients with high-grade (>50%) carotid stenosis versus asymptomatic patients with high-grade (>50%) carotid stenosis. All patients upon inclusion will undergo: Clinical, neurological evaluation Blood tests SMI, CEUS and SWE ultrasound Carotid MRI PET (subgroup) DW-MRI Histological assessments after the removal of plaque at carotid endarterectomy (CEA). Study 2: SMI and vascular events. Asymptomatic patient's follow-up at 12 months: Clinical neurological evaluation Blood test SMI, CEUS, SWE ultrasound Carotid MRI PET (subgroup) Study 3: This study will use the same patient pool described in study 1 undergoing the previously described procedural examinations upon inclusion and at one year follow up. Quantification of stiffness/elasticity in the artery wall will be performed and compared to plaque echogenicity measured as GSM . These results will be correlated to histology of the carotid plaque after trombendarterectomy, risk markers in blood (lipids, HbA1c, CRP, leukocytes), other cardiovascular risk markers (hypertension, diabetes, nicotine) and cerebrovascular symptoms.

Official Title
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Advanced Ultrasound Methods in the Assessment of Carotid Plaque Instability.

Conditions
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Internal Carotid Artery Stenosis With Infarction

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Atherosclerotic carotid stenosis >50% with or without cerebrovascular symptoms. Exclusion Criteria: Malignancies Inflammatory disease

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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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Raised neovascularization and increased stiffness of the carotid artery wall are correlated to cerebrovascular symptoms and raised level of some plasma markers. | Ultrasound (including SMI, CEUS, SWI), blood test, clinical symptoms and cerebral MRI at inclusion and at one year follow-up | one year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Increased neovascularization in the carotid artery wall assessed by SMI ultrasound is correlated to cerebrovascular symptoms, ischemic lesions on cerebral MR, increased level of some plasma markers and increased vascularization on carotid plaques | Ultrasound, blood tests, clinical assessment, cerebral MRI, histology of carotid artery plaques (if treated with carotid endarterectomy) | At inclusion | 
| Increased neovascularization in the carotid artery wall assessed by SMI ultrasound is correlated to cerebrovascular symptoms, ischemic lesions on cerebral MR and increased level of some plasma markers at one year follow-up | Clinical assessment, ultrasound, cerebral MRI, blood tests, histology if removed carotid plaque | 1 year | 
| Increased stiffness in the carotid artery wall assessed by ultrasound (GSM) is correlated to cerebrovascular symptoms and increased level of some plasma markers at one year follow-up | Clinical assessment, ultrasound, cerebral MRI, blood tests, histology if removed carotid plaque | 1 |