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Abstract #4291

Simultaneous PRF and T1-Mapping Based MR Thermometry for Monitoring High-Intensity Focused Ultrasound Ablation of Primary Bone Tumors

Adam C. Waspe1, Charles Mougenot2, Samuel Pichardo3, Thomas Looi1, Joao Amaral4, Michael Temple4, Hai-Ling Margaret Cheng5, James M. Drake1

1Division of Neurosurgery, Hospital for Sick Children, Toronto, Ontario, Canada; 2Philips Healthcare Canada, Markham, Ontario, Canada; 3Thunder Bay Regional Research Institute, Thunder Bay, Ontario, Canada; 4Department of Medical Imaging, Hospital for Sick Children, Toronto, Ontario, Canada; 5Department of Physiology & Experimental Medicine, The Hospital for Sick Children, Toronto, Ontario, Canada

MR-guided focused ultrasound is currently used for palliation of bone metastasis pain. Temperature is monitored using the proton resonance frequency (PRF) shift technique. PRF-thermometry is limited to water-based tissues and temperature is not measured in bone and marrow, limiting its use for primary tumor treatment. We hypothesize that marrow temperature can be quantified by measuring T1 change during heating, and that the temperature distribution across the bone can be modeled from the surrounding temperatures at the bone-muscle interface and marrow. This abstract introduces a MATLAB-based research tool to simultaneously measure temperature in muscle and fat using a hybrid PRF-T1 technique.

Keywords

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