alll patients have been included

Ischemic strokes account for more than 80% of strokes. Ischemic strokes are caused by the occlusion of an intracranial artery by a thrombus, responsible for tissue ischemia related to a decrease in local cerebral blood flow (CBS). Thus, the management of patients with Ischemic strokes is based on the preservation of an area that maintains sufficient intracranial hemodynamics (IH) and achieves the fastest possible recanalization. The impact of the patient's position (supine or seated position) on the IH in the event of narrowing or occlusion of an artery is poorly assessed but may be of particular importance. In practice, variations in blood flow according to the positioning of the patient's body can be measured using a transcranial Doppler. It is a simple, non-invasive and painless examination that provides the patient's bed with data on the intracerebral hemodynamic profile of patients.

This study was implemented because there are no studies known to us that evaluate the effect of verticalization on intracerebral hemodynamics based on the presence of upstream arterial stenosis or occlusion and other multimodal evaluation data in transcranial Doppler.

Inclusion criteria

• Patient over 18 years of age
• acute ischemic stroke or transient ischemic attack
• symptoms onset < 48 hours
• Absence of homolateral or downstream intracranial stenosis or M1 occlusion
• Verticalization authorized by the referent clinician.
• Rankin's score before AIC/AIT ≤ 2
• Non-opposition to participation in the study

Criteria for inclusion of cases

- Carotid stenosis of more than 50% NASCET or an occlusion

Criteria for including witnesses - Absence of carotid stenosis greater than 50% NASCET or occlusion

Criteria for non-inclusion

- Disrupted vigilance

Patient with ischemic stroke or transient ischemic attack of less than 48 hours with or without carotid stenosis greater than 50% NASCET or occlusion