Liu H B, Brugger R M, Laster B H, Greenberg D D, Gordon C R, Warkentien L S
Medical Department, Brookhaven National Laboratory, Upton, New York 11973, USA.
Med Phys. 1995 May;22(5):591-5. doi: 10.1118/1.597546.
As a follow-on study to the feasibility of neutron capture therapy (NCT) with 235U brachytherapy seeds, physical doses were calculated and measured for the radiation from a 235U foil in a lucite phantom which was irradiated at the epithermal neutron irradiation port of the Brookhaven Medical Research Reactor. In addition, cell survival experiments were performed to obtain the relative biological effectiveness (RBE) for the neutron part of the radiation. The calculated absorbed doses agree with the measured ones. From cell survival experiments, it is deduced that the fission neutrons from the 235U foil have a RBE of 3.0 while the fast neutrons in the beam have a RBE of 3.8. Also observed is that, with the cells 7 mm from the foil, a significant amount of absorbed dose comes from the beta rays of 235U fission events. This absorbed dose from beta rays is a significant addition to the therapeutic dose. Due to the limited ranges of beta rays in tissue, this absorbed dose is restricted to the vicinity of the foil. This is the first demonstration of beta rays as part of NCT.
作为使用235U近距离治疗种子进行中子俘获治疗（NCT）可行性的后续研究，对置于有机玻璃模型中的235U箔片在布鲁克海文医学研究反应堆的超热中子辐照端口进行辐照时所产生的辐射，计算并测量了其物理剂量。此外，还进行了细胞存活实验，以获得该辐射中子部分的相对生物效应（RBE）。计算得到的吸收剂量与测量值相符。从细胞存活实验推断，235U箔片产生的裂变中子的RBE为3.0，而束流中的快中子的RBE为3.8。还观察到，在距箔片7毫米处的细胞，有相当一部分吸收剂量来自235U裂变事件的β射线。这种来自β射线的吸收剂量是治疗剂量的一个重要补充。由于β射线在组织中的射程有限，这种吸收剂量仅限于箔片附近。这是首次证明β射线作为NCT的一部分。
Zotero 插件