Volume rendering algorithms for three-dimensional ultrasound imaging: Image quality and real-time performance analysis

One of the key additions to clinical ultrasound (US) systems during the last decade has been the incorporation of three-dimensional (3D) imaging as a native mode. These systems provide interactive volume rendering and display of 3D data. However, interactive volume rendering is challenging due to the large amount of data I/O and computation required. Many rendering techniques have been developed ranging from fast algorithms with lower image quality to sophisticated algorithms with better image quality, e.g., shear-warp, shear-image-order, pre-integration and direct ray casting. In this paper, we discuss pros and cons of each of these rendering algorithms in terms of algorithm complexity and image quality. We also discuss a new rendering algorithm that we have proposed: pre-integrated shear-image-order (PISIO). PISIO algorithm overcomes the image-quality limitations of other fast algorithms and provides a fine balance between computation and image quality. To demonstrate the interactive performance of these algorithms, we implemented them on a programmable multicore processor, i.e., IBM Cell processor. We present the results in this paper.