The possibility of the identification of the risk of rupture of a carotid plaque will have tremendous impact in clinical decision making. Firstly, in symptomatic patients with a 30-69% stenosis, who are currently not operated upon according to the current guidelines, identification of the risk of rupture plaque could identify patients who have a high risk of recurrent stroke, and would benefit of carotid intervention, such as endarterectomy or stent placement. This could potentially prevent a substantial number of strokes. Secondly, in all symptomatic patients with a 70-99% stenosis carotid intervention should be considered, according to the guidelines. However, only one out of six patients with a 70-99% stenosis benefits from a carotid intervention. Identification of patients with a high risk of a recurrent stroke would reduce the number of unnecessary interventions substantially.

The main objective is to show whether imaging characteristics assessed at baseline can predict clinical events in patients with a 30-69 % symptomatic carotid stenosis.

Inclusion Criteria:

• neurological symptoms due to ischemia in the carotid artery territory as diagnosed by their neurologist based on anamneses, physical examination and brain imaging (CT or MRI)
• carotid artery stenosis < 70% (upper cut-off value is based on the NASCET criteria, the lower cut-off value is an atherosclerotic plaque with a thickness of at least 2-3 mm, which corresponds to an ECST stenosis of 30%
• written informed consent

Exclusion Criteria:

• patients with probable cardiac source of embolism (rhythm disorders, mitral valve stenosis, prolapse or calcification, mechanical cardiac valves, recent myocardial infarction, left ventricular thrombus, atrial myxoma, endocarditis, dilated cardiomyopathy, patent foramen ovale) or a clotting disorder
• patients with evident other cause of neurological symptoms than carotid stenosis due to atherosclerotic disease (like demyelinating diseases, epilepsy, congenital brain disorders, aneurysms, fibromuscular dysplasia etc)
• patients already scheduled for carotid endarterectomy or stenting.
• severe co-morbidity, dementia or pregnancy
• standard contra-indications for MRI
• patients who have a documented allergy to MRI or CT contrast media
• patients with renal clearance < 30 ml/minute are not eligible to undergo contrast-enhanced MRI
• patients with renal clearance < 60 ml/minute are not eligible to undergo MDCT
• patients who had a TIA or minor stroke more than 3 months before inclusion

Patients with neurological symptoms due to ischemia in the carotid artery territory and with a carotid stenosis between 30-69% according to the ECST criteria will be included.