EuroVisShort2014

Permanent URI for this collection

https://diglib.eg.org/handle/10.2312/7747

Browse

Browsing EuroVisShort2014 by Subject "Applications"

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    Characterization of Blood-Flow Patterns from Phase-Contrast MRI Velocity Fields
    (The Eurographics Association, 2014) Pelt, Roy van; Fuster, Andrea; Claassen, Geert; Vilanova, Anna; N. Elmqvist and M. Hlawitschka and J. Kennedy
    Hemodynamic information has proven valuable for analysis of cardiovascular diseases. Aberrant blood-flow patterns,for instance, often relate to disease progression. Magnetic resonance imaging enables blood-flow measurementsthat provide three-dimensional velocity fields during one heartbeat. However, visual analysis of these data ischallenging, because of the abundance and complexity of information. Explicit feature extraction can facilitate thepattern characterization, and hence support visualization techniques to effectively convey anomalous flow areas.In this work, we improve on existing pattern matching methods that characterize blood-flow patterns in volumetricimaging data. To this end, we propose a set of helical and vortical patterns that can be parameterized by a singlevariable. The characterization performance is validated on both synthetic and imaging blood-flow data. Moreover,we present a comprehensive visualization based on the pattern matching results, enabling semi-quantitativeassessment of the patterns in relation to the cardiovascular anatomy.
  • Thumbnail Image
    Item
    Visualizing Uncertainty in HARDI Tractography Using Superquadric Streamtubes
    (The Eurographics Association, 2014) Wiens, Vitalis; Schlaffke, Lara; Schmidt-Wilcke, Tobias; Schultz, Thomas; N. Elmqvist and M. Hlawitschka and J. Kennedy
    Standard streamtubes for the visualization of diffusion MRI data are rendered either with a circular or with anelliptic cross section whose aspect ratio indicates the relative magnitudes of the medium and minor eigenvalues.Inspired by superquadric tensor glyphs, we propose to render streamtubes with a superquadric cross section,which develops sharp edges to more clearly convey the orientation of the second and third eigenvectors where theyare uniquely defined, while maintaining a circular shape when the smaller two eigenvalues are equal. As a secondcontribution, we apply our novel superquadric streamtubes to visualize uncertainty in the tracking direction ofHARDI tractography, which we represent using a novel propagation uncertainty tensor