Reduction of Motion Artifacts in Segmented EPI with Velocity Compensation Diffusion Gradients , for Application to Neonatal Imaging at 3 . 0 T

J. D. Winter, N. Gelman, P. A. Picot, D. S. Lee, Y. Bureau, R. T. Thompson Lawson Health Research Institute, Dept. of Medical Biophysics, University of Western Ontario, London, Ontario, Canada, Maternal and Newborn Health, St. Joseph's Health Care, London, Ontario, Canada SYNOPSIS: Diffusion MR images were acquired for 5 healthy adults and 1 neonate with a novel diffusion weighted (DW) segmented EPI sequence with velocity compensation (VC) diffusion gradients and navigator echo correction. Adult imaging results demonstrate the efficacy of motion suppression for the VC-DW sequence compared to conventional DW segmented EPI. VC gradients require a long TE resulting in considerable SNR losses in the adult brain. However in the neonatal brain, with long T2 values, losses in SNR are less as shown by estimates provided here. Therefore the VC-DW sequence is appropriate for neonatal brain imaging.