Fig 10. Pre- (A) and postoperative (B) tractograms of the ipsilateral superior longitudinal fasciculus for patient 4. The relative anatomic positions of the ipsilateral (red) and contralateral (green) tracts are shown superimposed onto coronal FA maps for the pre- (C) and postoperative (D) images. Preoperatively, the tract is deviated inferiorly because of the mass effect of the tumor (arrows) and consequently is positioned lower than the contralateral tract in coronal cross-section. Postoperatively, the tract appears to return to a more normal anatomic position and is positioned symmetrically with respect to the contralateral tract.