CT-ultrasound Registration For Ultrasound-guided Liver Intervention

A registration framework between preoperative CT and tracked2D intraopera-tive ultrasound (US) is presented for hepatic interventional therapy in this paper. Alandmark based registration method is frstly performed to get the initial registrationby using vessel bifurcations in US and their counterparts in CT. Then an optimizedBayesian Non Local Means flter is utilized to reduce speckle in US image and a sim-ulation model of US from CT scan is developed to simulate the major US efects.Finally, a new similarity metric incorporating spatial and intensity scale informationis proposed to register the selected US image containing crucial anatomical features(e.g. large vessel) and the simulated US from CT. The results of the registration arecompared to the Bronze Standard which is manually defned by a clinical expert in CTand US images. Experiments involving5patients’abdominal data demonstrate thatour registration framework achieved an average FRE and TRE of3.81±1.16mm and4.13±1.27mm.