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Publication Date: 2016-Dec-12
Document File: 1 page(s) / 171K

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The Prior Art Database

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Automated Voxel Position Optimization for In Vivo Magnetic Resonance Spectroscopy

MRS voxel placement in the hippocampus using anatomical images. The orange and yellow boxes indicate the

planned voxel location corresponding to the resonances of NAA and water, while the green box indicates the

shim volume.

The optmisation relates to MR spectroscopy, in which MR spectra data are acquired from localised

volumes, e.g. voxels based on gradient selection. That is , a limited bandwidth RF excitation is

employed together with spatially selective magnetic gradient fields. The gradient direction are adjusted so as to reduce sensitivity of voxel location close to tissue

boundaries. In this way the MR spectral acquisition is made less sensitive to chemical shifts of

volumes from which MR spectra of different chemical compounds are acquired. Further the local

shim volume to reduces B0 inhomgeneities is shifted away from tissue boundaries.

This reduces the error in MR spectrometry owing to chemical shifts and magnetic field shimming.

Poor water suppression and magnetic field shimming, as well as increased outer volume signal

bleed, are three of the most common sources of reduced MRS data quality that limit the clinical

utility of MRS. This invention reduces the dependence on local user expertise in MRS voxel planning

by enabling automated calculation of the optimal chemical shift displacement directions and shim

volume placement, leading to improved MRS data quality and reliability, and f...