High Spatial Resolution 23Na-MRI for Ischemic Brain Injury Detection

Abstract

Abstract High spatial resolution sodium ( 23 Na) imaging of brain lesions remains challenging due to the intrinsically low signal-to-noise ratio (SNR) of 23 Na-MRI compared with conventional proton ( 1 H) MRI. In this study, we established a high-resolution 23 Na-MRI platform based on 14 T preclinical scanner using a dual-tuned head-implanted RF coil. This configuration enables the acquisition of 1 H-based T 2 -weighted anatomical and diffusion-weighted imaging (DWI), as well as 23 Na-MRI, from the same animal. Brain-wide 23 Na-MRI with 300×300 µm 2 in-plane resolution was performed within the first 4 hours after acute middle cerebral artery occlusion (MCAO) induced ischemic stroke induction. Hyperintense 23 Na-MRI signals were observed in the ischemic brain regions, presenting a contrast-to-noise ratio (CNR) that exceeded that of T 2 -weighted images. Infarct regions can be well-identified in the elevated 23 Na signal, which is spatially consistent with regions of reduced apparent diffusion coefficient (ADC) values, indicating water restriction in the ischemic core. This work established implanted double-tuned 1 H/ 23 Na RF coils as a powerful approach for high-resolution 23 Na-MRI readout, facilitating the early detection of ischemic brain injury.

The authors' abstract, as published at the source. Translational Stroke Research, 2026 · DOI ↗