New detector for proton beam calibration
Nowadays, proton therapy is becoming one of the most powerful technique for cancer treatment, but the throughput (number of treated patients/day) is limited thus limiting its benefits despite the high investment cost. The dose has to be calibrated very precisely, making crucial the control of the beam before irradiation. Depending on the implemented approach, the current calibration methods are complex, expensive,limited in resolution, slow...
NECTAR project aims at improving the quality assurance clinical protocols by developing a complete system to calibrate proton beam before irradiation treatment. For the first time, we will implement a new approach based on robust gallium nitride (GaN) semiconductor that allows one to surpass by far the current techniques. Indeed, we propose to fabricate detector arrays that can instantly measure the proton beam on a 5x5cm2 window and with a resolution of 100 microns. A proof of concept with single elements has already been demonstrated and we expect now to develop a 2D array that will be qualified on the Nice hospital’s synchrotron line. NECTAR objectives combine several domains, from material science to medical instrumentation. This will be possible thanks to the specific expertise of the two teams involved: CNRS-CRHEA will bring its strong background of material science and optoelectronic devices while IMPT-CAL will provide its long experience on proton therapy and medical physics.
Our final imaging system will enable beam profile measurement in one shot. It will induce a drastic reduction of the calibration procedure duration down to only few minutes against more than 30 minutes currently. In consequence, it will allow increasing the number of treated patients at a constant cost, and thus will improve the healing success. The proposed approach also allow very high spatial resolution, much better than the current calibration technologies, which would induce benefits on the treatment accuracy itself.