TITLE:
Voxel Placement Precision for GABA-Edited Magnetic Resonance Spectroscopy
AUTHORS:
Xue Bai, Ashley D. Harris, Tao Gong, Nicolaas A. J. Puts, Guangbin Wang, Michael Schär, Peter B. Barker, Richard A. E. Edden
KEYWORDS:
MRS, Voxel Placement, Precision, Voxel Prescription, Registration
JOURNAL NAME:
Open Journal of Radiology,
Vol.7 No.1,
March
24,
2017
ABSTRACT: The purpose of the present study was to assess the reproducibility of voxel placement for GABA-edited MRS. GABA-edited MRS data were acquired in 13 healthy volunteers from (3 cm)3 voxel; and within the same session a second acquisition was independently prescribed. A three-dimensional voxel mask image was reconstructed in T1-image-space using the SVMask tool (in house software). Reproducibility of voxel placement was assessed using the Dice overlap coefficient, both within-subject and between-subject following co-registration of T1 images and transformation of voxel mask images to standard space. Within-subject overlap coefficients were 86% ± 5%. Between-subject overlap coefficients were 75% ± 10%. For the two voxel locations considered (occipital and sensorimotor), voxel overlap was very similar. Between-subject values are higher due to between-session effects, anatomical variability and volume mismatch in standard space. While surprisingly low in terms of volume overlap, the overlap coefficients correspond to acceptable linear displacements.