Matthew Bucknor1, Viola Rieke1, Youngho Seo1, Randall Hawkins1, Mark Wilson1, Sharmila Majumdar1, Thomas M. Link1, Maythem Saeed1
1Radiology & Biomedical Imaging, University of California, San Francisco, San Francisco, CA, United States
MR-guided high intensity focused ultrasound (MRgHIFU) is a powerful technique for thermally ablating focal lesions. The purpose of this study was to clearly delineate post-treatment changes in bone following HIFU on MR, PET and MDCT imaging in a swine model. Two discrete ovoid lesions were created at each proximal diaphysis and distal metadiaphysis of the right femur. Follow-up imaging studies at five days demonstrated focal ovoid hypoenhancement and decreased radiotracer uptake (dynamic 18NaF-PET) which correlated precisely to the prescribed targets. CT failed to demonstrate the lesions. This study supports the usage of MRgHIFU in treating focal lesions in bone.