Related Experiment Video
Updated: Apr 20, 2026

Magnetic Resonance Imaging of Multiple Sclerosis at 7.0 Tesla
Published on: February 19, 2021
Automatic voxel positioning for MRS at 7 T
Weiqiang Dou1, Oliver Speck, Thomas Benner
1Faculty for Natural Sciences, Biomedical Magnetic Resonance, Otto-von-Guericke University, ZENIT Building, Leipziger Str. 44, 39120, Magdeburg, Germany.
Object:
The purpose of this study was to test, for the first time, whether spectroscopy voxels could be positioned automatically with high accuracy and reproducibility in ultrahigh-field longitudinal magnetic resonance spectroscopy (MRS) studies.
Materials And Methods:
MRS voxels were automatically positioned in two cingulate subregions of 12 healthy subjects using a vendor-provided automatic voxel positioning (AutoAlign) technique, and were manually placed in the same regions of 10 healthy subjects by an experienced technician in three 7 T MRS scan sessions. Different coils were used for manual (24-channel coil) and automatic (32-channel coil) voxel placement, and the effects of signal-to-noise-ratio differences on the spectra were considered.
Results:
Over three scan sessions and two regions scanned for each subject, a mean voxel geometric overlap ratio of 0.91 for automatic positioning reflected accurate voxel alignment, while the geometric overlap ratio was only 0.70 for voxels placed manually. Comparable voxel positions among the three scan sessions (p > 0.05) indicated high reproducibility of automatic voxel alignment. In comparison, significant voxel displacement among scan sessions (p < 0.05) was found using manual voxel positioning.
Conclusions:
In view of the highly accurate and reproducible voxel alignment with automatic voxel positioning, we propose the application of automatic rather than manual voxel positioning in future ultrahigh-field longitudinal MRS studies.
More Related Videos
Related Concept Videos
Magnetic Resonance Imaging
NMR Spectrometers: Resolution and Error Correction
Atomic Nuclei: Magnetic Resonance
NMR Spectrometers: Overview
NMR Spectrometers: Radiofrequency Pulses and Pulse Sequences

