Aneurysmal subarachnoid hemorrhage (SAH) is a devastating form of stroke, with three major complications : early brain injury (EBI), vasospasm and delayed cerebral ischemia (DCI). Those patients are often given care in neurocritical care. Imaging is particularly useful to diagnose these complications. Brain imaging includes CT scan, MRI and arteriography which are not easily available and need an intrahospital transportation. Furthermore, intrahospital transportation of critically ill patients is associated with significant complications Here, investigators try to show that a new non-invasive bedside device, based on 3D enhanced ultrasonography, is able to detect principal arteries of anterior circulation of the brain.

Introduction: Aneurysmal subarachnoid hemorrhage (SAH) is a devastating form of hemorrhagic stroke. Majors complications of aneurysmal SAH include early brain injury (EBI), vasospam and delayed cerebral ischemia (DCI). There are currently only few ways through imaging to diagnose those complication. Transcranial doppler (TCD) is an accessible bedside tool which is efficient, but can only provide indirect evidences. Other brain imaging includes CT scan, MRI and arteriography which are not easily available and are associated with intrahospital transportation of critically ill patients and its morbidity. There are several preclinical evidences that 3D enhanced ultrasonography localizing microscopy could show similar images resolution to angiography while being more accessible.

Materials and methods: this study will include patients with aneurysmal SAH. Aneurysm must be of anterior circulation.The investigators will perform a feasibility research with a new medical device based on ultrasonography localizing microscopy. The standard of care will not be changed, but each patient will also get three bilateral transcranial enhanced (with microbubbles from Sonovue) ultrasonography, one for each period at risk (J0-J2, J4-10, J11-J14). The primary outcome will be the quality of time-intensity curve of the contrast agent, in order to show the quality of signal received. Then, as a secondary outcome, images will be compared to clinical findings. As a pilot study, the investigators plan to include only 15 patients in a monocentric trial.

This device could provide real-time information on blood flow and potential complications such as vasospasm or DCI, allowing for earlier intervention and potentially improving outcomes for SAH patients. Additionally, the bedside nature of this device eliminates the need for intrahospital transportation, reducing the risk of complications associated with moving critically ill patients.

This study aims to assess the feasibility and potential benefits of using 3D enhanced ultrasonography localizing microscopy in the management of aneurysmal SAH. The results of this pilot study could pave the way for larger clinical trials and ultimately lead to improved outcomes for patients with this devastating condition.

Inclusion Criteria:

• Admitted in neurologic ICU of the CHU Caen, Normandy, for a subarachnoid hemorrhage of the anterior circulation.
• Usable ultrasound temporal window.
• 18 years old and more.
• Consent of the participant or the trusted person.

Exclusion Criteria:

• non-aneurysmal subarachnoid haemorrhage.
• Contraindication to ultrasound contrast agent Sonovue, including allergies to a compound.
• Uncontrolled systemic hypertension.
• Acute respiratory distress syndrome.
• Pregnancy or breastfeeding mother.
• Vulnerable person with guardianship or curatorship.
• Patient not affiliated to french social security system (Sécurité Sociale)

IPD won't be shared with other researchers. Data will be collected in a data base with an authentification by password. The used system is in accordance with the french law, notably MR-01. Only permitted person will be given an access to the data base. Every connection to the data base will be recorded.

The investigator and care provider can't see the imaging results.