Impacts of retrospective lipid suppression on metabolite quantification in preclinical proton MR spectroscopic imaging
Year: 2026
Type: preprint
Abstract: Extracranial lipid contamination remains a challenge in proton magnetic resonance spectroscopic imaging (MRSI), especially in short acquisition delay MRSI, where broad lipid resonances overlap with metabolite and macromolecular signals. Although retrospective lipid suppression techniques are widely used in human MRSI, their effects on metabolite quantification in preclinical MRSI, which is more prone to lipid contamination, have not yet been examined. In this study, we assessed how the retrospective lipid suppression and spectral fitting range influence spectral quality, spatial metabolite mapping, and quantification variability using proton MRSI of rat brains at 14.1 T. Lipid suppression was applied via an orthogonal projection method to both fully sampled and compressed sensing datasets, each comprising data with minimal and pronounced lipid contamination. Spectral fitting was performed with both broad (4.1 - 0.2 ppm) and narrow (4.1 - 1.8 ppm) ranges. When lipid contamination was minimal, suppression caused only slight spectral and spatial changes, with consistent metabolite quantification across conditions. In contrast, datasets with pronounced lipid contamination exhibited notable spectral changes following suppression, consequently affecting spatial metabolite mapping and concentration estimates. Group analysis revealed that metabolites with low concentration estimates were most affected. Similar effects were observed in compressed sensing datasets. Our results provide a better understanding of the impact of retrospective lipid suppression on metabolite quantification in preclinical MRSI, thereby supporting future optimizations for its effective application.
Language: English
Subfield: Radiology, Nuclear Medicine and Imaging
Field: Medicine
Domain: Health Sciences
Open Access status: green
Awards: Enhanced MR Spectroscopic mapping of brain regional changes in type C hepatic encephalopathy of juvenile rats to develop novel combinatorial treatments, SHEDDING LIGHT ON THE INVISIBLE: MAPPING BRAIN MICROSTRUCTURE USING DIFFUSION MAGNETIC RESONANCE SPECTROSCOPIC IMAGING, Developments of innovative fast acquisition and metabolic modelling strategies for clinical and preclinical deuterium MR imaging in the brain at ultra-high field
OpenAlex ID: W7213892442