Carotid Plaque Assessment Using 18Fluorine (18F) -Sodium Fluoride Positron Emission Tomography (PET) /MR

Carotid plaque can lead to ischemic stroke. Treatment of asymptomatic carotid plaque, based on degree stenosis, is still controversial. Beyond the degree of stenosis, the composition of the plaque could reflect the vulnerability and the risk of ipsilateral ischemic stroke. Identification of new predictive factor of ipsilateral ischemic stroke in patients with carotid plaque could help to screen high risk patients and to guide the treatment. The aim of the study is to assess 18F-sodium fluoride uptake among carotid plaque in recently symptomatic and asymptomatic patients. Investigators conduct a pilot case-control study. Twelve patients (6 recently symptomatic and 6 asymptomatic) with carotid stenosis (≥50% NASCET) will have a 18F-sodium fluoride PET/MR. Standardized uptake value (SUV) and tissue-to-background ratio (TBR) will be measured among carotid plaques.