Plausibility Tracking: A method to evaluate anatomical connectivity and microstructural properties along fiber pathways

• Published in: NeuroImage (Orlando, Fla.) Vol. 90; pp. 163 - 178
• Main Authors: Schreiber, Jan, Riffert, Till, Anwander, Alfred, Knösche, Thomas R.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Inc 15.04.2014; Elsevier; Elsevier Limited
• Subjects: Adult; Algorithms; Biological and medical sciences; Brain - anatomy & histology; Brain Mapping - methods; Brain research; Child; Diffusion MRI; Diffusion Tensor Imaging - methods; Female; Fiber density; Fundamental and applied biological sciences. Psychology; Global tractography; Humans; Image Processing, Computer-Assisted; Male; Methods; Microstructural metrics; Nerve Fibers - ultrastructure; Neural Pathways - anatomy & histology; Spherical deconvolution; Tract-based analysis; Tractography; Vertebrates: nervous system and sense organs; GRAPPA; ILF; fODF; MRI; MNI; PFC; SLF; FS; dMRI; CHARMED; SD; CSD; MC; IFOF; MD; Global tractography; Spherical deconvolution; BA45; AFDmax; CC; AD; Tractography; HARDI; ROI; CR; MAD; RD; Fiber density; Diffusion MRI; FA; Tract-based analysis; Microstructural metrics; FD; AFD; Density; Nuclear magnetic resonance imaging
• ISSN: 1053-8119; 1095-9572; 1095-9572
• DOI: 10.1016/j.neuroimage.2014.01.002

Diffusion MRI is a non-invasive method that potentially gives insight into the brain's white matter structure regarding the pathway of connections and properties of the axons. Here, we propose a novel global tractography method named Plausibility Tracking that provides the most plausible pathway, modeled as a smooth spline curve, between two locations in the brain. Compared to other tractography methods, plausibility tracking combines the more complete connectivity pattern of probabilistic tractography with smooth tracks that are globally optimized using the fiber orientation density function and hence is relatively robust against local noise and error propagation. It has been tested on phantom and biological data and compared to other methods of tractography. Plausibility tracking provides reliable local directions all along the fiber pathways which makes it especially interesting for tract-based analysis in combination with direction dependent indices of diffusion MRI. In order to demonstrate this potential of plausibility tracking, we propose a framework for the assessment and comparison of diffusion derived tissue properties. This framework comprises atlas-guided parameterization of tract representation and advanced bundle-specific indices describing fiber density, fiber spread and white matter complexity. We explore the new method using real data and show that it allows for a more specific interpretation of the white matter's microstructure compared to rotationally invariant indices derived from the diffusion tensor. •Framework to compare bundle specific parameters derived from dMRI across subjects•Introduction of a new global tractography method called “Plausibility Tracking”•Fast and reliable initialization through probabilistic tractography•More specific results compared to analysis with indices of diffusion tensor