Abstract:
PURPOSE:To assess volumetric proton MR spectroscopic imaging (MRSI) of the human brain on multivendor MRI instruments. METHODS:Echo-planar spectroscopic imaging was developed on instruments from three manufacturers, with matched specifications and acquisition protocols that accounted for differences in sampling performance, radiofrequency (RF) power, and data formats. Intersite reproducibility was evaluated for signal-normalized maps of N-acetylaspartate (NAA), creatine (Cre), and choline using phantom and human subject measurements. Comparative analyses included metrics for spectral quality, spatial coverage, and mean values in atlas-registered brain regions. RESULTS:Intersite differences for phantom measurements were less than 1.7% for individual metabolites and less than 0.2% for ratio measurements. Spatial uniformity ranged from 79% to 91%. The human studies found differences of mean values in the temporal lobe, but good agreement in other white matter regions, with maximum differences relative to their mean of under 3.2%. For NAA/Cre, the maximum difference was 1.8%. In gray matter, a significant difference was observed for frontal lobe NAA. Primary causes of intersite differences were attributed to shim quality, B0 drift, and accuracy of RF excitation. Correlation coefficients for measurements at each site were over 0.60, indicating good reliability. CONCLUSION:A volumetric intensity-normalized MRSI acquisition can be implemented in a comparable manner across multivendor MR instruments.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Sabati M,Sheriff S,Gu M,Wei J,Zhu H,Barker PB,Spielman DM,Alger JR,Maudsley AAdoi
10.1002/mrm.25510subject
Has Abstractpub_date
2015-11-01 00:00:00pages
1209-20issue
5eissn
0740-3194issn
1522-2594journal_volume
74pub_type
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