Integrated registration and visualization of medical image data

Different imaging modalities give insight to vascular, anatomical and functional information which assist diagnosis and therapy planning in medicine. Registration and consecutive visualization allow to combine the image data and thereby convey more meaningful images to the clinician. Applying a voxel based approach based on mutual information, accurate and retrospective registration is provided. However, optimization and consecutive visualization procedures require a huge amount of trilinear interpolation operations to re-sample the data. Ensuring fast performance which is fundamental for medical routine, we suggest an integrated approach which takes advantage of the imaging and texture mapping subsystem of graphics computers. All trilinear interpolation is completely performed with hardware assisted 3D texture mapping. The 1D and 2D histograms of the datasets which are necessary for the calculation of mutual information are obtained with different hardware accelerated imaging operations. For the simultaneous and interactive visualization of the registered datasets a new approach was developed which allows for versatile fusion operations. Using similar procedures supported by hardware, contributes considerably to accelerate registration and visualization. Implementing our approach within a previously presented framework (Hastreiter et al., 1996) (Sommer et al., 1998) based on OpenInventor and OpenGL provides intuitive manipulation. Clinical examples show the value of our approach in practice