GPU-based Multi-Volume Rendering for the Visualization of Functional Brain Images

Nowadays, medical imaging procedures provide a great variety of data obtained with different modalities. To offer a deeper insight into this data the simultaneous visualization of these images, not regarding their source, must be provided. One example is the field of functional brain imaging, where the activation of brain regions during cognitive tasks is measured. This data has to be visualized whitin its anatomical context the brain in order to have an spatial impression of the position of the activation. To that end, multi-volume visualization must be supported. In this paper we describe a flexible framework for GPU-based multi-volume rendering, which provides a correct overlaying of an arbitrary number of volumes and allows the visual output for each volume to be controlled independently. We also present, a visualization tool specific for the rendering of functional brain images, we built on top of this framework. This tool includes different GPU-based volume rendering techniques, on the one hand for the interactive visual exploration of the data, and on the other hand for the generation of high-quality visual representations. We demonstrate the effectiveness of our tool with data gathered from a cognitive study, in regard to performance and quality results.