Exploring Metabolic Aberrations after Intracerebral Hemorrhage In Vivo with Deuterium Metabolic Spectroscopy Imaging

Aberrations in metabolism after intracerebral hemorrhage (ICH), particularly lactate metabolism, play a crucial role in the pathophysiology and patient outcome. To date, the evaluation of metabolism relies heavily on invasive methods such as microdialysis, restricting a comprehensive understanding of the metabolic mechanisms associated with ICH. This study proposes a noninvasive metabolic imaging method based on 2 H magnetic resonance spectroscopy and imaging ( 2 H-MRS/MRSI) to detect metabolic changes after ICH in vivo. To overcome the low-sensitivity limitation of 2 H, we designed a new 1 H– 2 H double-resonance coil with 2 H-channel active detuning and proposed chemical shift imaging based on the balanced steady-state free precession method (CSI-bSSFP). Compared with the volume coil, the signal-to-noise ratio (SNR) of the new coil was increased by 4.5 times. In addition, the SNR of CSI-bSSFP was 1.5 times higher than that of conventional CSI. These two technologies were applied to measure lactate metabolic flux at different phases of ICH. The results show a higher lactate concentration in ICH rats than in control rats, which is in line with the increased expression of lactate dehydrogenase measured via immunohistochemistry staining (AUC Lac_area/Glc_area: control, 0.08 ± 0.02 vs ICH-3d, 0.39 ± 0.05 vs ICH-7d, 0.18 ± 0.02, P < 0.01; H-score: control, 126.4 ± 5.03 vs ICH-3d, 168.4 ± 5.71 vs ICH-7d,133.6 ± 7.70, P < 0.05). A higher lactate signal also appeared near the ICH region than in normal brain tissue. In conclusion, 2 H-MRS/MRSI shows potential as a useful method for in vivo metabolic imaging and noninvasive assessment of ICH.