Clinical procedures that are conventionally guided by 2D x-ray imaging, may benefit from the additional spatial information provided by 3D image data. For instance, guidance of minimally invasive procedures with CT or MRI data provides 3D spatial information and visualization of structures that are not visible with x-ray. Since 3D imaging modalities may not be available during the procedure or require increased patient dose, it is desirable to use pre-interventional/preoperative 3D patient data for guidance that was obtained for diagnosis and treatment planning. To accomplish this, a...