Carotid Atherosclerosis : Innovative Imaging Biomarkers. Study Case-control
Carotid Atherosclerosis : Innovative Imaging Biomarkers. Study Case-control
Cerebrovascular accident (CVA) constitutes a major health public problem. This represents the
 second cardiovascular death cause. CVA is ischemic in 80% of cases. Atheroma of large
 arteries, mainly carotid, is involved in about 20% of cases.

 After several high grade studies (NASCET, ECST, ACAS, ACST), carotid surgery is based on
 stenosis calculation by Doppler ultrasound, CT angiography, MRI angiography or arteriography.

 The composition of the plaque, showing its vulnerability, is associated with embolic risk and
 stroke. The therapeutic strategy based only on the narrowing of the arterial lumen is not
 satisfactory enough to prevent the occurrence of a transient ischemic attack (TIA) or an
 ipsilateral stroke due to carotid stenosis. Thus, new techniques emerge, to evaluate in vivo
 the inflammation of the plaque, its embolic consequences or the mechanical stress it
 undergoes. These techniques are: High Resolution MRI (HR MRI), evaluation of the Gray Scale
 Median (GSM) level, study of the plaque vascularization with Contrast Enhanced ultrasound
 (CEUS), High Intensity Transient Signals (HITS) by transcranial Doppler, micro RNA profile
 (mi RNA). These different modalities must be combined in order to increase the efficiency.

 Based on these encouraging results, the investigator aim at evaluating the ability of
 different methods or their combination to predict the occurrence of ischemic stroke or TIA
 due to emboli from a carotid atherosclerotic plaque. Before considering a cohort study, he
 investigator want to evaluate the performance of each of these new methods in the
 characterization of carotid plaque instability. Performance evaluation will allow us to
 choose secondarily the most relevant association.

 The investigator propose, as a first step, to make a case-control study with these methods,
 the cases are patients who had an ischemic stroke (authenticated by both the clinical exam
 and brain MRI) on the same side as the carotid stenosis and the controls are patients with
 carotid stenosis but without ischemic stroke. This study is a cross-sectional study because
 it simultaneously measures the occurrence of the event (ischemic stroke) and the
 characteristics of the atheromatous plaque.

 Over a 2 year period, 45 symptomatic patients and 105 asymptomatic patients will be included
 with a carotid stenosis with at least a 50% caliber constriction according to NASCET
 criteria. (North American Symptomatic Carotid Endarterectomy Trial).
Inclusion Criteria:

 -  Carotid stenosis ≥ 50% NASCET

 -  Case: ipsilateral carotid stenosis stroke, certified by MRI or CT in the preceding
 month, with no others causes of stroke

 -  Control: no clinical sign or MRI hint for a recent stroke

 -  Signed informed consent form

 -  Patient affiliated to a social security system or equivalent

 Exclusion Criteria:

 -  Modified Rankin scale > 3

 -  Homolateral stroke or TIA > 1 month

 -  Medical history of homolateral carotid surgery, cervical radiation, carotid occlusive,
 homolateral intracranial stenosis, risk of developing arterial thromboembolic events

 -  Renal failure (creatinine clearance < 50 ml/min)

 -  Contraindication to ultrasound (sonovue)

 -  Contraindication to MRI and its contrast media (Gadolinium)

 -  Inability to sign informed consent

 -  Inability to undergo any of the technics (claustrophobia…)

 -  Serious co-morbid disease, dementia

 -  Neurological disease with no carotid disease

 -  Risk of pregnancy or pregnancy or breastfeeding

 -  Adult under reinforced guardianship or legal guardian

 -  Patient not understanding French