Wu Qingbiao, Wang Qingbin, Liang Tianjiao, Zhang Gang, Ma Yinglin, Chen Yu, Ye Rong, Liu Qiongyao, Wang Yufei, Wang Huaibao
China Spallation Neutron Source (CSNS), Institute of High Energy Physics (IHEP), Chinese Academy of Sciences (CAS), Dongguan 523803, People's Republic of China; Dongguan Institute of Neutron Science (DINS), Dongguan 523808, People's Republic of China.
Dongguan Institute of Neutron Science (DINS), Dongguan 523808, People's Republic of China; China Spallation Neutron Source (CSNS), Institute of Physics (IPHY), Chinese Academy of Sciences (CAS), Dongguan 523803, People's Republic of China.
Appl Radiat Isot. 2016 Sep;115:235-250. doi: 10.1016/j.apradiso.2016.06.029. Epub 2016 Jun 28.
At present, increasingly more proton medical facilities have been established globally for better curative effect and less side effect in tumor treatment. Compared with electron and photon, proton delivers more energy and dose at its end of range (Bragg peak), and has less lateral scattering for its much larger mass. However, proton is much easier to produce neutron and induced radioactivity, which makes radiation protection for proton accelerators more difficult than for electron accelerators. This study focuses on the problem of patient-induced radioactivity during proton treatment, which has been ignored for years. However, we confirmed it is a vital factor for radiation protection to both patient escort and positioning technician, by FLUKA's simulation and activation formula calculation of Hengjian Proton Medical Facility (HJPMF), whose energy ranges from 130 to 230MeV. Furthermore, new formulas for calculating the activity buildup process of periodic irradiation were derived and used to study the relationship between saturation degree and half-life of nuclides. Finally, suggestions are put forward to lessen the radiation hazard from patient-induced radioactivity.
目前，全球范围内建立了越来越多的质子医疗设施，以便在肿瘤治疗中获得更好的疗效和更少的副作用。与电子和光子相比，质子在其射程末端（布拉格峰）传递更多的能量和剂量，并且由于其质量大得多，横向散射较少。然而，质子更容易产生中子和感生放射性，这使得质子加速器的辐射防护比电子加速器更困难。本研究聚焦于质子治疗期间患者产生的放射性问题，该问题多年来一直被忽视。然而，通过对横建质子医疗设施（HJPMF）进行FLUKA模拟和活化公式计算，其能量范围为130至230MeV，我们证实这对患者陪护人员和定位技术人员的辐射防护而言是一个关键因素。此外，推导了用于计算周期性照射活度积累过程的新公式，并用于研究核素的饱和度与半衰期之间的关系。最后，提出了减少患者产生的放射性带来的辐射危害的建议。
