Role of Neuroinflammation and Blood-Brain Barrier Breakdown in Intracerebral Hemorrhage.

Intracerebral Hemorrhage (ICH) is the most devastating stroke subtype that affects > 3 million people worldwide each year. Despite important efforts and the hope that minimally invasive surgical procedures may offer, there is currently no effective treatment. Perihematomal edema - a surrogate marker of neuroinflammation - has emerged as important contributors to poor functional outcome following acute ICH, and a potential treatment target. Innovative techniques have been developed to image and measure neuroimmune response (TSPO PET) and BBB integrity (DCE-MRI). These novel methods have been poorly studied in ICH. The effects of in vivo perihematomal neuroinflammation on the functional outcome of patients with acute ICH is widely unknown.

The present study is a prospective, multicenter study of patients with acute spontaneous supratentorial ICH (within 48h after onset). Each participant will have a standardized multimodal evaluation of neuroinflammation at 10 days after onset including TSPO PET using 18F-DPA-714 radioligand, BBB imaging using DCE-MRI and a panel of pro-inflammatory and anti-inflammatory plasma biomarkers.

In hospital follow up visit will occur at 14 days and end of follow up visit at 180 days. Functional outcome will be assessed by modified Rankin scale (mRS), which is a widely used and validated scale - ranging from 0 (no symptoms) to 6 (death) - to evaluate the functional outcome following ischemic or hemorrhagic strokes.

Inclusion criteria

• Adults (≥ 18 years old);
• presenting with a symptomatic spontaneous supratentorial ICH;
• ICH within 48 hours after symptoms onset (or last seen well);
• ICH confirmed by brain imaging;
• Informed consent documented;
• Affiliated or beneficiary of social security scheme.

Exclusion criteria

• Massive ICH volume (≥ 60 ml) at admission;
• Severe coma (defined as a Glasgow Coma Scale score < 6) at admission;
• Planned neurosurgical hematoma evacuation;
• Decision already taken for palliative care with withdrawal of active treatment;
• Pre-existing dependance defined as a mRS score ≥2 prior to ICH occurrence;
• Underlying secondary cause of ICH including macrovascular causes (brain arteriovenous malformation, intracranial aneurysm, dural arteriovenous fistula, cavernous malformation), brain tumour, cerebral venous thrombosis, hemorrhagic infarction. Patients taking oral anticoagulant can be included;
• TSPO genotyping demonstrating a low affinity binder profile,
• Unable to tolerate or contraindicated to brain MRI: medical material not MRI compatible, claustrophobia, known hypersensitivity to gadoteric acid, meglumin or any drug containing gadolinium;
• Estimated glomerular filtration rate < 30 ml/min/1.73 m 2
• Unable to tolerate or contraindicated to 18F-DPA714 PET: women who are pregnant or breastfeeding, claustrophobia, and known hypersensitivity to DPA-714;
• Use of Benzodiazepines within 7 days (within 6 weeks for prazepam, diazepam or clorazepate) preceding TSPO PET acquisition;
• Co-existing neuroinflammatory disease such as Multiple Sclerosis, Neuromyelitis optica, Neurosarcoidosis, autoimmune encephalitis, CNS vasculitis;
• Conditions requiring long-term immunosuppressive medication;
• Expected impossible follow-up or poor compliance;
• Patient under tutorship, curatorship, or legal protection.