Gated Optical DetectorsDose Guided Radiotherapy

使用现有原型探测器系统的所有体模研究均已完成。 该系统还成功地用于测量新获得的输出因子 具有非常小的孔径的立体定向施源器。用Monte Carlo方法对测量结果进行了验证 卡罗计算以及辐射变色胶片。该项目已达到其直到一个 商业原型已经生产出来了。为该任务选择的原始公司无法 在规定的时间内完成这样一个单位，并已违约的条款， 协议NRL正在选择一家新公司，但在此之前， 如果新公司不能生产出可行的装置，这个项目就不能再进一步了。一旦这个 发生，有2个额外的后续项目：（1）一个三阶段的项目，以开发一个 用于剂量引导放射治疗的探测器阵列，或DGR。第一阶段是开发一种纤维阵列 作为矩形或螺旋形网格，并研究放射治疗期间生成的剂量图 以及器官或射束定位的小变化的影响。第二阶段是了解 相对于患者的解剖位置的信号变化的意义，并中断 如果检测到的信号与参考值相差预定公差，则进行处理 裕度第三阶段是动态地将电网信号的变化与 用于放射治疗的在线、动态剂量控制的辐射场。(2)单独的 开发胶片式光释光剂量计以取代照相胶片的项目， 剂量测定。使用分散在膜上的研磨OSL玻璃的初步测量 具有粘合剂基底是有希望的，但必须找到更好的方法来生产OSL 大小均匀的颗粒。一种可能的方法是使用纳米粒子 我们目前正在与一位学术界人士合作， 研究机构探索这种可能性。

All phantom studies with the existing prototype detector system have been completed. The system was also used successfully to measure the output factor of newly acquired stereotactic applicators with very small apertures. The measurements were validated with Monte Carlo calculations as well as with radiochromic film. This project has reached its until a commercial prototype is produced. The original company selected for this task was unable to complete such a unit in the allotted time frame and has defaulted on the terms of its agreement. NRL is in the process of selecting a new company, but until this is done and the new company can produce a workable unit, this project cannot progress further. Once this happens, there are 2 additional follow-on projects: (1) a three phase project to develop a detector array for dose-guided radiotherapy, or DGR. Phase I is to develop an array of fibers as either a rectangular or spiral grid and study the dose map generated during radiotherapy and the effect of small changes in organ or beam positioning. Phase II is to understand the meaning of signal change relative to the patient's anatomical position and to interrupt the treatment if detected signals differ from reference values by a predetermined tolerance margin. Phase III is to dynamically link the changes in grid signals to corrective changes in the radiation field for on-line, dynamic dose control of radiation treatments. (2) a separate project to develop a film-based OSL dosimeter as a replacement for photographic film for dosimetry measurements. Preliminary measurements using ground OSL glass dispersed on a film substrate with a binder were promising, but better methods must be found to produce OSL particles that are uniform in size. One possible approach is to employ nanoparticles incorpoprating OSL molecular chains, and we are currently partnering with an academic institution to explore this possibility.