Added Value of Sodium MR Imaging and Proton MR Spectroscopy to Conventional MR Imaging for a Better Characterization of the Ischemic Stroke: A Narrative Review.

Stroke is a major cause of disability and death in adults worldwide. In clinical setting, time efficient MRI protocols including diffusion weighted images, fluid attenuated inversion recovery, fast T2*-weighted images and MR angiography aim to establish ischemic stroke diagnosis, visualize vessel occlusion and determine the extent of ischemia damage distinguishing between the salvageable ischemic penumbra and the infarct core. Thus, MRI plays a pivotal role in diagnosis, treatment decision-making, and prognostic assessment, although prediction based on these elements remains limited and can be improved. We reviewed the added-values of alternative MRI methods such as sodium(²³Na) MRI and ¹H MR spectroscopic imaging that open new temporal and pathophysiological windows on ionic dys-homeostasis and metabolism alteration in the context of ischemic stroke and reperfusion. Insights on the timeline of the cellular events accessible using these alternative methods and perspectives to improve clinical outcome prediction of ischemic stroke patients are discussed.