Post on 31-Dec-2015
description
Quality Assessment for Quality Assessment for Routine Clinical MR Routine Clinical MR
SpectroscopySpectroscopy
Diana M. Lindquist, PhDAssistant Professor of Radiology
PurposePurpose Clinical indication: apparently abnormal metabolite
ratios in infant with normal imaging findings. Quality control is as important in clinical spectroscopy
as in research Develop a simple short protocol for quality control in
clinical MRS Localization Spectral data
MethodsMethods Standard head coil and
manufacturer’s phantom
Protocol Axial localizer 3 voxels (8 cm3) PRESS
Total time: 30 minutes
Results: Image UniformityResults: Image Uniformity
Results: Voxel LocalizationResults: Voxel Localization Mean voxel size was
20.2 (± 0.8) by 18.9 (± 0.4) mm2 in-plane
One voxel is adequate; scan time reduced from 30 to 15 minutes
Sample spectraSample spectra
TE 35 ms TE 144 ms
Lac
NAA
CrCho
Results: Metabolite RatiosResults: Metabolite RatiosTE
35msTE
144ms
NAA/Cr 1.50 ± 0.03
1.64 ± 0.04
Cho/Cr 0.84 ± 0.01
0.68 ± 0.02
mI/Cr 0.47 ± 0.02
N/A
ConclusionsConclusions Following implementation of this protocol, we
are now able to detect and correct scanner instabilities.
QC data are useful as a monitor of system performance
Scheduling still difficult even with a 15 minute exam.