This is a prospective study including acute ischemic stroke patients aged 18 to 90. Multidetector raw CT is performed in acute ischemic stroke patients. Heart, neck vessels and brain arteries are studied during the same acquisition. Results are compared with the standard methods including transesophageal echocardiography (TEE), Doppler ultrasound (DUS) and MR angiography (MRA) of neck vessels. The main criteria is the ability of CT to classify the stroke etiology correctly according to the TOAST classification in comparison with the standard methods.

Inclusion Criteria:

• Acute (< 1 week) ischemic stroke patient aged 18 to 90
• Informed consent obtained
• Presence of health insurance

Exclusion Criteria:

• Pregnancy or absence of efficient contraceptive method
• Allergy
• Allergy to contrast material
• Asthma
• Renal failure (blood creatinine > 130 µmoles/l, creatinine clearance < 80 ml/mn according to Cockroft method)
• Myeloma
• Hyperthyroidism (uncontrolled)
• Difficulties to synchronize CT to heart rhythm
• Contra-indication to TEE or MRI
• Absence or retirement of informed consent
• Absence of health insurance