Fiber based comparison of whole brain tractographies with application to amyotrophic lateral sclerosis

Abstract

A method is proposed for comparison between whole brain white matter tractographies derived from Diffusion Tensor Imaging (DTI) scans. The method performs fiber based comparisons between DTI-derived parameter values sampled along the fibers. The individual tractographies and the parameters sampling are done in each brain’s native space. No non-linear registration to a common space is required. Our method for fiber based comparison is especially useful as a first exploratory step in neurologic population studies. It provides pointers to the locations affected by the pathology of interest in the study. It is fully automatic and does not make any grouping assumptions on the fibers. The results are presented on a single fiber resolution level and any sub-group or tract of interest can be examined. The validation of the method was conducted using a set of scans from an Amyotrophic Lateral Sclerosis (ALS) study and comparing the outcome to previous findings.