John H. Woo1, Elias R. Melhem1, Sumei Wang1, Lauren Elman2, Leo McCluskey2, Lisa Desiderio1, Hui Zhang1, James Gee1
1Radiology, University of Pennsylvania, Philadelphia, PA, USA; 2Neurology, University of Pennsylvania, Philadelphia, PA, USA
Amyotrophic lateral sclerosis (ALS) is a degenerative disease of motor neurons. Using diffusion tensor imaging, previous investigators have measured a reduction in fractional anisotropy (FA) in the corticospinal tract, thought to reflect axonal degeneration. However, these methods often required manual segmentation or individual fiber tractography to generate regions-of-interest (ROI). In this study, we performed whole-tract FA measurements using a deformable tensor-driven registration algorithm and a weighted 3D ROI of the CST in template space. We found a highly significant difference between 12 ALS patients and 7 controls. This method may be especially useful for evaluating whole-tract differences in large groups.