{"about":{"site":"https://codewithpapers.app","non_affiliation":"Code with Papers and Syntology are not affiliated with, endorsed by, or sponsored by Papers with Code, Meta, or the pwc-archive mirror.","licence":"CC BY-SA 4.0","licence_url":"https://creativecommons.org/licenses/by-sa/4.0/legalcode","attribution":"https://codewithpapers.app/attribution","modified":"archive material modified by Syntology; see the attribution page"},"url":"/paper/reducing-variability-in-along-tract-analysis","title":"Reducing variability in along-tract analysis with diffusion profile realignment","arxiv_id":"1902.01399","date":"2019-02-04","proceeding":"arXiv 2019 2","authors":["Samuel St-Jean","Maxime Chamberland","Max A. Viergever","Alexander Leemans"],"abstract":"Diffusion weighted MRI (dMRI) provides a non invasive virtual reconstruction\nof the brain's white matter structures through tractography. Analyzing dMRI\nmeasures along the trajectory of white matter bundles can provide a more\nspecific investigation than considering a region of interest or tract-averaged\nmeasurements. However, performing group analyses with this along-tract strategy\nrequires correspondence between points of tract pathways across subjects. This\nis usually achieved by creating a new common space where the representative\nstreamlines from every subject are resampled to the same number of points. If\nthe underlying anatomy of some subjects was altered due to, e.g. disease or\ndevelopmental changes, such information might be lost by resampling to a fixed\nnumber of points. In this work, we propose to address the issue of possible\nmisalignment, which might be present even after resampling, by realigning the\nrepresentative streamline of each subject in this 1D space with a new method,\ncoined diffusion profile realignment (DPR). Experiments on synthetic datasets\nshow that DPR reduces the coefficient of variation for the mean diffusivity,\nfractional anisotropy and apparent fiber density when compared to the unaligned\ncase. Using 100 in vivo datasets from the HCP, we simulated changes in mean\ndiffusivity, fractional anisotropy and apparent fiber density. Pairwise\nStudent's t-tests between these altered subjects and the original subjects\nindicate that regional changes are identified after realignment with the DPR\nalgorithm, while preserving differences previously detected in the unaligned\ncase. This new correction strategy contributes to revealing effects of interest\nwhich might be hidden by misalignment and has the potential to improve the\nspecificity in longitudinal population studies beyond the traditional region of\ninterest based analysis and along-tract analysis workflows.","url_abs":"http://arxiv.org/abs/1902.01399v1","url_pdf":"http://arxiv.org/pdf/1902.01399v1.pdf","source":{"archive":"pwc-archive (Hugging Face), CC BY-SA 4.0","snapshot":"2025-07-28","licence_url":"https://creativecommons.org/licenses/by-sa/4.0/legalcode","row_kind":"abstracts"},"code_links":[{"paper_slug":"reducing-variability-in-along-tract-analysis","repo_url":"https://github.com/samuelstjean/dpr","is_official":1,"mentioned_in_paper":1,"mentioned_in_github":0,"framework":"none","reach":null}],"tasks":[{"task_slug":"anatomy","task_name":"Anatomy"},{"task_slug":"specificity","task_name":"Specificity"}],"methods":[],"datasets_introduced":[],"methods_introduced":[],"results":[],"syntology":{"atlas_url":null,"mcp":null,"developers":"https://syntology.ai/developers"},"arxiv_metadata":null,"syntology_extracted_results":null}