Contrast enHanced-IonoAcoustics in Proton and heavy Ion beam therapy (CHIAPI)

• Applicants: Dr. Julie Lascaud, Ph.D.; Professorin Dr. Katia Parodi
• Subject Area: Medical Physics, Biomedical Technology
• Term: since 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 540410528

Ion beam therapy allows for a local irradiation of deep-seated tumors, reducing the treatment toxicity in the surrounding healthy tissue. Yet, because of an inaccurate knowledge of the tissue stopping properties and possible changes of the patient anatomy, the in vivo position of the maximum of the dose (Bragg peak) may differ from the original treatment plan. Ionoacoustics aims to retrieve the Bragg peak position by detecting the thermoacoustic waves induced by the energy deposition of pulsed ion beams. Accurate co-registration between the ionoacoustics-based reconstructed dose and ultrasound imaging of the patient anatomy could allow to monitor the radiotherapeutic treatment in almost real-time, possibly enabling intra and/or inter-fraction adaptation of the treatment strategy. However, the measurement of the ionoacoustic signals at clinical energies is challenging due to the weak pressures generated (10-100 mPa) and their low frequency range (10-100 kHz). To overcome the detection limits, we propose to explore the use of contrast agents, aiming to enhance the ionoacoustic emissions and improve the co-registration with other imaging modalities (e.g., ultrasound or X-ray imaging). The key objectives of the project are to identify the agents which would be the most beneficial to a strong acoustic emission, and to broaden the use of ionoacoustics-based range verification to continuous and heavy ion beams, i.e., from synchrotron accelerators, a priori not favourable to acoustic emissions.

• DFG Programme: Research Grants