In recent years there has been increased interest throughout the world in the use of proton radiation therapy for treatment of cancer. Currently, there are only 9 operational centers in the US that treat a total of about 7,000 patients per year comprising less than 1% of all patients that receive radiation therapy. However, at least 30% of patients would benefit from treatment with proton beams. The capital and operating cost of extant systems is a major limiting factor. One attractive option being developed by at least two commercial suppliers is based on compact high field superconducting synchrocyclotron (SCSC) technology developed at MIT. The SCSC has many attractive features such as cost, size and ease of operation. However, it has one potential major drawback due to the very low duty cycle whereby beam pulses of about 10 ns in duration occur about 1000 times per second. Real-time detectors currently in clinical practice have several deficiencies for utilization with short pulse beams such as delivered by a SCSC, A detector that can measure these small, short duration, beam spots in real-time and provide feedback is required. The overall goal for this SBIR project is to perform the research needed to develop an innovative detector that would be suitable for the above application. ProCure proposes a novel technique that takes advantage of the very short proton SCSC pulse to measure only the fast scintillation light from direct atomic excitations in Zenon within a narrow time gate of about 100ns following the proton pulse thus avoiding the problem of ion recombination that occur over a much longer time scale. We emphasize that this scheme, based on fast emitted light detection and fast electronics, will achieve linear response and no saturation when used with intense sub-microsecond beam pulses. In Phase I, the research team will concentrate on developing a working prototype detector and measuring its parameters. Based on the results of these studies in Phase II ProCure will focus on the engineering and construction of full-scale 30?30 cm2 detectors as well as design of custom data acquisition electronics. This will be followed by the comprehensive testing required for FDA 510k approval, leading to a final marketable product.
Proton therapy provides the best possible option for using radiation to control and eliminate tumors with the least short and long term toxic side effects but its utilization is restricted by the size and cost of extant equipment. One attractive option being commercialized is based on compact high field superconducting synchrocyclotrons (SCSC) technology. However existing detectors used in clinical practice are not capable of monitoring the dose from such a machine and the novel detector proposes here by ProCure is required to do so and consequently help to bring this highly effective form of cancer treatment to the mainstream of radiation therapy in a more affordable option.
| Vigdor, S E; Klyachko, A V; Solberg, K A et al. (2017) A gas scintillator detector for 2D dose profile monitoring in pencil beam scanning and pulsed beam proton radiotherapy treatments. Phys Med Biol 62:4946-4969 |
