Methods and statistics for diffusion MRI tractometry

Analyzing microstructural properties projected along white matter pathways derived from diffusion magnetic resonance imaging (MRI) has become increasingly popular in recent years. Along-streamline profiling based on diffusion MRI tractometry is a framework that maps summary measures of the diffusion data (e.g., fractional anisotropy) at multiple points along a given pathway, resulting in a so-called bundle-profile. In this chapter, we introduce the various steps involved in along-streamline profiling, covering concepts related to bundle segmentation, core streamline definition, and statistical analysis of bundle-profiles. Our aim is to provide a general overview of the tractometry framework and to encourage its application.