Three-dimensional registration and fusion of ultrasound and MRI using major vessels as fiducial markers

This paper describes fusion of three-dimensional (3-D) ultrasound (US) and magnetic resonance imaging (MRI) data sets, without the assistance of exter nal fiducial markers or external position sensors. Fusion of these two moda lities combines real-time 3-D ultrasound scans of soft tissue with the larg er anatomical framework from MRI. The complementary information available f rom multiple imaging modalities warrants the development of robust fusion c apabilities. We describe the data acquisition, specialized algorithms, and results for 3-D fused data from phantom studies and in vivo studies of the normal human vasculature and musculoskeletal systems.