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Reproducibility of fMRI in the clinical setting: Implications for trial designs

2008; Elsevier BV; Volume: 42; Issue: 2 Linguagem: Inglês

10.1016/j.neuroimage.2008.05.005

1095-9572

Rose Bosnell, Christiane Wegner, Zsigmond Tamás Kincses, T. Korteweg, Federica Agosta, Olga Ciccarelli, Nicola De Stefano, Achim Gass, Joy Hirsch, Heidi Johansen‐Berg, Ludwig Kappos, Frederik Barkhof, Laura Mancini, Francesco Manfredonia, Silvia Marino, D. H. Miller, Xavier Montalbán, Jacqueline Palace, Maria A. Rocca, Christian Enzinger, S Ropele, Àlex Rovira, Stephen M. Smith, Alan J. Thompson, John S. Thornton, Tarek Yousry, Brandon Whitcher, Massimo Filippi, Paul M. Matthews,

Functional Brain Connectivity Studies

With expanding potential clinical applications of functional magnetic resonance imaging (fMRI) it is important to test how reliable different measures of fMRI activation are between subjects and sessions and between centres. This study compared variability across 17 patients with multiple sclerosis (MS) and 22 age-matched healthy controls (HC) in 5 European centres performing an fMRI block design with hand tapping. We recruited subjects from sites using 1.5 T scanners from different manufacturers. 5 healthy volunteers also were studied at each of 4 of the centres. We found that reproducibility between runs and sessions for single individuals was consistently much greater than between individuals. There was greater run-to-run variability for MS patients than for HC. Measurements of maximum signal change (MSC) appeared to provide higher reproducibility within individuals and greater sensitivity to differences between individuals than region of interest (ROI) suprathreshold voxel counts. The variability in measurements between centres was not as great as that between individuals. Consistent with these observations, we estimated that power should not be reduced substantially with use of multi-, as opposed to single-, centre study designs with similar numbers of subjects. Multi-centre interventional studies in which fMRI is used as an outcome measure thus appear practical even when implemented in conventional clinical environments.