NSF Award
2301721
High Intensity Focused Ultrasound thermal ablation is an FDA approved cancer therapy that uses high frequency ultrasound to thermally ablate cancer tissues. A long-standing barrier in using this therapy to achieve desired therapeutic outcomes for deeper cancers is the need to use high energy ultrasound to achieve deeper ultrasound penetration, leading to detrimental heating of the neighboring wave passage regions. One potential method to overcome this barrier is to introduce microbubbles in the target region, while using moderate energy ultrasound, to generate higher temperature elevations in the target region without elevating the temperature of the neighboring healthy tissues. The main aim of this project is to elucidate through numerical simulations, the fundamental understanding of how microbubbles can help in efficient ablation of tissues without causing damage to surrounding tissues. The project will also encompass significant education activities including undergraduate research projects and outreach activities for high school students.<br/><br/>The technical goal of the proposed research is to simulate and quantify the bubble-acoustics-thermal field interaction phenomenon in microbubble assisted focused ultrasound based thermal ablation therapy. To address this goal a numerical model will be developed that can simulate non-linear ultrasound propagation through tissues, its interaction with a microbubble cloud and the resulting thermal field. The model will be validated using both in vitro and ex vivo experimental data. The validated model will then be used to answer two previously unanswered questions: (i) what is the fundamental mechanism through which microbubbles enhance heat transfer from ultrasound to the tissues? (ii) what combination of microbubble parameters and ultrasound parameters can give rise to an optimal heat deposition in the target region without causing damage to the surrounding tissues? The proposed research will help in achieving a breakthrough in using microbubble assisted ultrasound therapy for cancer treatment by accurately characterizing the acoustic and thermal fields in the presence of microbubbles. This will enable researchers to explore a wide range of therapeutically relevant parameters and optimize design settings with confidence when developing focused ultrasound-based therapies.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
