Tractography in Context: Multimodal Visualization of Probabilistic Tractograms in Anatomical Context

Displaying neurological data from multiple imaging modalities in anatomical context is a challenging task in biomedical visualization. We present an application-driven approach, which solves the visibility issues of simultaneous presentation of focus and context. The tractogram (a scalar field indicating a connectivity score between voxels) is visualized by nested surface layers, providing an overview of long-range connectivity. Unique dataset features are reflected by value-based opacity, and further enhanced by depth cues. Anatomical context is given as an illustrative, threedimensional rendering of the cortex complemented with textured slices. Two user studies were performed to evaluate our methods and we adapted our techniques based on their feedback. With the presented methods, the nature of the tractogram becomes clear even in static images, while it allows to perceive the information and the context simultaneously. Our methods can be applied to a wide range of data, as they can be adapted to different data ranges and requirements very easily.