Respiratory motion tracking of skin and liver in swine for CYBERKNIFE motion compensation

In this study, we collected respiratory motion data of external skin markers and internal liver fiducials from several swine. The POLARIS infrared tracking system was used for recording reflective markers placed on the swine's abdomen. The AURORA electromagnetic tracking system was used for recording 2 tracked needles implanted into the liver. This data will be used to develop correlation models between external skin movement and internal organ movement, which is the first step towards the ability to compensate for respiratory movement of the lesion. We are also developing a motion simulator for validation of our model and dose verification of mobile lesions in the CYBERKNIFE Suite. We believe that this research could provide significant information towards the development of precise radiation treatment of mobile target volumes.