Reconstructing the somatotopic organization of the corticospinal tract remains a challenge for modern tractography methods
This work addresses the problem of accurately mapping the corticospinal tract for neuroscience and clinical applications, but it is incremental as it compares existing methods without introducing new ones.
The study evaluated six tractography methods for reconstructing the corticospinal tract and its somatotopic organization using Human Connectome Project data, finding that while progress has been made on lateral projections, comprehensive reconstruction including clinically important areas remains a challenge.
The corticospinal tract (CST) is a critically important white matter fiber tract in the human brain that enables control of voluntary movements of the body. Diffusion MRI tractography is the only method that enables the study of the anatomy and variability of the CST pathway in human health. In this work, we explored the performance of six widely used tractography methods for reconstructing the CST and its somatotopic organization. We perform experiments using diffusion MRI data from the Human Connectome Project. Four quantitative measurements including reconstruction rate, the WM-GM interface coverage, anatomical distribution of streamlines, and correlation with cortical volumes to assess the advantages and limitations of each method. Overall, we conclude that while current tractography methods have made progress toward the well-known challenge of improving the reconstruction of the lateral projections of the CST, the overall problem of performing a comprehensive CST reconstruction, including clinically important projections in the lateral (hand and face area) and medial portions (leg area), remains an important challenge for diffusion MRI tractography.