Assessment of bundle-specific axon diameter distributions using diffusion MRI tractography

The main limitation of diffusion tractography for connectivity studies is that the reconstructed tractograms are not truly quantitative. Microstructure imaging allows the estimation of more quantitative features of the neuronal tissue, such as the axon diameter distribution, but this analysis can only be performed voxelwise. Here, we extend a framework that we recently proposed for evaluating the plausibility of tractograms (COMMIT) with the aim of assessing bundle-specific axon diameter distributions as well. This possibility may have implications in connectomics, as it opens new perspectives for investigating brain connectivity at different scales.