Clues from 1H MR spectroscopy about the cerebral micro-environment of ingested ethanol

Motivation: The methylene MRS signal of cerebral ethanol was reported invisible by some and fully-detectable by others. Goal(s): Elucidate reasons for the limited visibility of a submoiety of a cerebral molecule Approach: Record various single-voxel and MRSI data before/after ethanol ingestion to investigate MT-effects (with/without water-presaturation), resonance-frequency-dependence (spectra from 1.5T, 3T, 7T), T2-relaxation (multiple TEs), molecular diffusion properties (diffusion-weighted MRS using short diffusion-times and double-diffusion-encoding), and compartmental effects (MRSI and WM/GM/CSF-differentiation) Results: Detectability of CH2-signals of brain ethanol varies with moiety-specific, B0-dependent T2-relaxation and appears brain-compartment specific. Magnetization-exchange doesn't play a role and diffusion properties don't evidence stable binding to large molecules/structures Impact: The explored partial and B0-dependent detectability of brain ethanol may give insight into its microenvironment and could scale with the extent of physiologic effects. Ethanol's differential and field-dependent T2s may serve as prototype for studying binding properties of endogenous metabolites.