Simulating Thermal Effects of MR-guided Focused Ultrasound (MRgFUS) in Cortical Bone and its Surrounding Tissue

High intensity focused ultrasound (HIFU) has been proposed as an alternative treatment for osteoid osteoma and bone metastases. To overcome current issues planning and monitoring HIFU procedures, this project proposes a simulator that predicts the temperature distribution during therapy. The bone is segmented from MR images using a semi-automatic algorithm, acoustic calculations are performed using the Rayleigh integral, and thermodynamic calculations using Pennes' Bioheat equation. The algorithm segmented with a sensitivity of 85 ± 4% and a mean volume error of 5 ± 11%. The simulation had a maximum temperature error of -2.4 ± 11.7°C, had a spatial error of 3.61 ± 1.61mm, and could be computed in less than 40s on over 10^8 points. Although these results were deemed insufficiently accurate for clinical software, the fast computation time and the modifiable framework have shown that this project was a first step in developing a clinically relevant simulation.M.A.S