Ben Jeurissen1, Maarten Naeyaert1, Alexander Leemans2, Jan Sijbers1
1Vision Lab, Dept. of Physics, University of Antwerp, Antwerp, Belgium; 2Image Sciences Institute, University Medical Center Utrecht, Utrecht, Netherlands
Misalignment between diffusion weighted (DW) images and the corresponding gradient orientations leads to misinterpretation of rotationally variant diffusion parameters and tractography results. We propose a method to automatically correct for rigid misalignment of the gradient orientations, using a registration metric based on the average fiber trajectory length. Using simulations we show that our method converges to the 'ground truth' orientations and that small 'angulation' errors can still be detected, that are easily overlooked by visual inspection. While the method uses diffusion tensor tractography to calculate trajectory lengths, the recovered gradient orientations can be applied in general DWI post-processing.