NEX or No NEX? a High Angular Resolution Diffusion Imaging Study

Maxime Descoteaux¹, Nicolas Wiest-Daessl², Sylvain Prima², Christian Barillot², Rachid Deriche³, Cyril Poupon¹

The need for multiple NEX and averaging along each diffusion gradient direction is shown to be unnecessary. This can significantly reduce acquisition time. We show that a proper filtering of the diffusion measurements correcting the Rician noise bias can increase the quality and coherence of HARDI reconstructions and anisotropy maps while preserving the angular resolution of the reconstruction method.