Estimation of apparent diffusion coefficient (ADC) of three major metabolites measured in human brain at 3T

Motivation: A diffusion-weighted stimulated echo acquisition (DW-STEAM) spectroscopy sequence was implemented to assess metabolite compartments in the human brain. Goal(s): The study aims to analyse key brain metabolites by using diffusivity and quantitation. Approach: Several diffusion gradient configurations of a diffusion weighted STEAM sequence were used to obtain a range of b-values. Phantom experiments were conducted, and in vivo data acquired from healthy volunteers. Results: Distinct ADCs for metabolites. NAA showed the lowest ADC, indicating restricted diffusion in neurons. Cr had intermediate values, aligning with its role in energy metabolism. Cho exhibited the highest ADC, suggesting less restricted diffusion linked to membrane activity. Impact: Non-invasive quantification of metabolic diffusion and regional metabolic profile characterization can enhance neurological disorder diagnostics. This study shows diffusion-weighted spectroscopy's potential to assess in vivo metabolic profiles, refining biomarkers for early diagnosis and treatment monitoring, and improving clinical outcomes.