Multi-Fiber Tractography Visualizations for Diffusion MRI Data

Abstract

In recent years, several new diffusion MRI approaches have been proposed to explore microstructural properties of the white matter, such as Q-ball imaging and spherical deconvolution-based techniques to estimate the orientation distribution function. These methods can describe the estimated diffusion profile with a higher accuracy than the more conventional second-rank diffusion tensor imaging technique. Despite many important advances, there are still inconsistent findings between different models that investigate the “crossing fibers” issue. Due to the high information content and the complex nature of the data, it becomes virtually impossible to interpret and compare results in a consistent manner. In this work, we present novel fiber tractography visualization approaches that provide a more complete picture of the microstructural architecture of fiber pathways: multi-fiber hyperstreamlines and streamribbons. By visualizing, for instance, the estimated fiber orientation distribution along the reconstructed tract in a continuous way, information of the local fiber architecture is combined with the global anatomical information derived from tractography. Facilitating the interpretation of diffusion MRI data, this approach can be useful for comparing different diffusion reconstruction techniques and may improve our understanding of the intricate white matter network.

Trade-off between angular and spatial resolutions in in vivo fiber tractography

“…At the regions where these fibers cross, the CST is the dominant fiber population, and is the easiest to model accurately with low angular resolutions. The non-dominant fiber populations, the AF and the lateral projections of the corpus callosum, are known to be less accurate at lower angular resolutions (Vos et al 2013b) and consequently produce erroneous tract reconstructions (Fig. 9).…”

Diffusion tensor imaging of the auditory nerve in patients with long-term single-sided deafness

“…The DTI acquisition was therefore optimized to minimize the distortions by limiting the FOV in the phase-encoding (AP) direction to 79 mm. This reduced the distortions to a level significantly lower than for standard neuroscientific (factor 2.5 compared to e.g., Vos et al, 2013) and standard clinical protocols (factor 1.5 compared to e.g., Reijmer et al, 2012), even for the higher spatial resolution of our data.…”

Diffusion MRI visualization

“…Models for multi‐fiber tractography contain even richer information at each point in space. It has been visualized by placing ODF glyphs along the curve or by creating hyperstreamlines with cross‐sections indicating secondary fiber directions …”