Abstract #0768

Johansen-Berg H, Heiervang E, Behrens T, Robson M, Mackay C

Diffusion MR and tractography are increasingly used to generate quantitative measures for clinical studies. Interpretation of such results depends on a good understanding of the variability of these measures but evidence on this variability is limited. We scanned 8 subjects on 3 occasions to characterise within and between subject variability of quantitative diffusion measures including histogram measures of fractional anisotropy (FA), ROI analyses of FA, and measures generated from tractography. The variability measures that we present can be used to estimate required sample sizes to detect differences between populations.