RT Journal Article
SR Electronic
T1 A Validation Study of Multicenter Diffusion Tensor Imaging: Reliability of Fractional Anisotropy and Diffusivity Values
JF American Journal of Neuroradiology
JO Am. J. Neuroradiol.
FD American Society of Neuroradiology
SP 695
OP 700
DO 10.3174/ajnr.A2844
VO 33
IS 4
A1 R.J. Fox
A1 K. Sakaie
A1 J.-C. Lee
A1 J.P. Debbins
A1 Y. Liu
A1 D.L. Arnold
A1 E.R. Melhem
A1 C.H. Smith
A1 M.D. Philips
A1 M. Lowe
A1 E. Fisher
YR 2012
UL http://www.ajnr.org/content/33/4/695.abstract
AB BACKGROUND AND PURPOSE: DTI is increasingly being used as a measure to study tissue damage in several neurologic diseases. Our aim was to investigate the comparability of DTI measures between different MR imaging magnets and platforms. MATERIALS AND METHODS: Two healthy volunteers underwent DTI on five 3T MR imaging scanners (3 Trios and 2 Signas) by using a matched 33 noncollinear diffusion-direction pulse sequence. Within each subject, a total of 16 white matter (corpus callosum, periventricular, and deep white matter) and gray matter (cortical and deep gray) ROIs were drawn on a single image set and then were coregistered to the other images. Mean FA, ADC, and longitudinal and transverse diffusivities were calculated within each ROI. Concordance correlations were derived by comparing ROI DTI values among each of the 5 magnets. RESULTS: Mean concordance for FA was 0.96; for both longitudinal and transverse diffusivities, it was 0.93; and for ADC, it was 0.88. Mean scan-rescan concordance was 0.96–0.97 for all DTI measures. Concordance correlations within platforms were, in general, better than those between platforms for all DTI measures (mean concordance of 0.96). CONCLUSIONS: We found that a 3T magnet and high-angular-resolution pulse sequence yielded comparable DTI measurements across different MR imaging magnets and platforms. Our results indicate that FA is the most comparable measure across magnets, followed by individual diffusivities. The comparability of DTI measures between different magnets supports the feasibility of multicentered clinical trials by using DTI as an outcome measure. CVcoefficient of variationFAfractional anisotropyλ⊥transverse diffusivityλ‖longitudinal diffusivityMPRAGEmagnetization-prepared rapid acquisition of gradient echoTIMTotal Imaging Matrix