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Updated: May 20, 2026

Measuring Interactions of Globular and Filamentous Proteins by Nuclear Magnetic Resonance Spectroscopy (NMR) and Microscale Thermophoresis (MST)
Published on: November 2, 2018
Real-time dynamic frequency and shim correction for single-voxel magnetic resonance spectroscopy
1Department of Medicine, John A. Burns School of Medicine, University of Hawaii, Honolulu, Hawaii, USA. brianrk@hawaii.edu
Abstract:
Subject motion during brain magnetic resonance spectroscopy acquisitions generally reduces the magnetic field (B₀) homogeneity across the volume of interest or voxel. This is the case even if prospective motion correction ensures that the voxel follows the head. We introduce a novel method for rapidly mapping linear variations in B₀ across a small volume using two-dimensional excitations. The new field mapping technique was integrated into a prospectively motion-corrected single-voxel ¹H magnetic resonance spectroscopy sequence. Interference with the magnetic resonance spectroscopy measurement was negligible, and there was no penalty in scan time. Frequency shifts were also measured continuously, and both frequency and first-order shim corrections were applied in real time. Phantom experiments and in vivo studies demonstrated that the resulting motion- and shim-corrected sequence is able to mitigate line broadening and maintain spectral quality even in the presence of large-amplitude subject motion.
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