Characterization of Peri-Hemorrhagic Cerebral Edema Using Synthetic Sodium Imaging With 7-Tesla and 3-Tesla MRI

Intracerebral haemorrhage is the type of stroke with the highest mortality rate, estimated at 40% in the acute phase. Among survivors, half will experience functional disability. Currently, there is no validated effective treatment. Reduction of perihematomal oedema is a potential therapeutic target. The development of oedema in the days following the haemorrhage worsens functional prognosis, notably through a harmful inflammatory process. In the early phase, neuronal excitotoxicity induced by the hematoma plays a major role in triggering the inflammatory cascade. This phenomenon is associated with dysfunction of neuronal Na⁺/K⁺ ATPase pumps and a disturbance of cerebral sodium homeostasis. Ultra-high field 7T MRI enables in vivo quantification of brain sodium concentrations. The investigators hypothesize that a drop-in sodium concentration within the perihematomal oedema is associated with greater oedema expansion and poorer functional outcome. To make this biomarker accessible to centers without 7 Tesla MRI, the investigators will use an artificial intelligence algorithm to generate synthetic sodium concentration maps derived from data acquired on conventional 3 Tesla MRI.