title: Reconstruction of white matter tracts via repeated deterministic streamline tracking--initial experience.
abstract: Diffusion Tensor Imaging (DTI) and fiber tractography are established methods to reconstruct major white matter tracts in the human brain in-vivo. Particularly in the context of neurosurgical procedures, reliable information about the course of fiber bundles is important to minimize postoperative deficits while maximizing the tumor resection volume. Since routinely used deterministic streamline tractography approaches often underestimate the spatial extent of white matter tracts, a novel approach to improve fiber segmentation is presented here, considering clinical time constraints. Therefore, fiber tracking visualization is enhanced with statistical information from multiple tracking applications to determine uncertainty in reconstruction based on clinical DTI data. After initial deterministic fiber tracking and centerline calculation, new seed regions are generated along the result's midline. Tracking is applied to all new seed regions afterwards, varying in number and applied offset. The number of fibers passing each voxel is computed to model different levels of fiber bundle membership. Experimental results using an artificial data set of an anatomical software phantom are presented, using the Dice Similarity Coefficient (DSC) as a measure of segmentation quality. Different parameter combinations were classified to be superior to others providing significantly improved results with DSCs of 81.02%±4.12%, 81.32%±4.22% and 80.99%±3.81% for different levels of added noise in comparison to the deterministic fiber tracking procedure using the two-ROI approach with average DSCs of 65.08%±5.31%, 64.73%±6.02% and 65.91%±6.42%. Whole brain tractography based on the seed volume generated by the calculated seeds delivers average DSCs of 67.12%±0.86%, 75.10%±0.28% and 72.91%±0.15%, original whole brain tractography delivers DSCs of 67.16%, 75.03% and 75.54%, using initial ROIs as combined include regions, which is clearly improved by the repeated fiber tractography method.
authors.affiliation: Department of Neurosurgery, University of Marburg, Marburg, Germany. bauermi@med.uni-marburg.de
authors.forename: Miriam H A
authors.initials: MH
authors.lastname: Bauer
authors.forename: Daniela
authors.initials: D
authors.lastname: Kuhnt
authors.forename: Sebastiano
authors.initials: S
authors.lastname: Barbieri
authors.forename: Jan
authors.initials: J
authors.lastname: Klein
authors.forename: Andreas
authors.initials: A
authors.lastname: Becker
authors.forename: Bernd
authors.initials: B
authors.lastname: Freisleben
authors.forename: Horst K
authors.initials: HK
authors.lastname: Hahn
authors.forename: Christopher
authors.initials: C
authors.lastname: Nimsky
mesh_terms: D000328:Adult; D000368:Aged; D001921:Brain; D001931:Brain Mapping / Q000379:methods*; D001932:Brain Neoplasms / Q000503:physiopathology; D016022:Case-Control Studies; D056324:Diffusion Tensor Imaging; D005260:Female; D005909:Glioblastoma / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D008959:Models, Neurological; D009434:Neural Pathways; D019047:Phantoms, Imaging; D011712:Pyramidal Tracts / Q000503:physiopathology*; D012984:Software