Gated Optical DetectorsDose Guided Radiotherapy

已进行体模研究。初步研究报告已经发表，正在准备对剂量测定参数进行全面评估。商业原型将于9月中旬交付进行评估。由于人事变动和优先事项的转移，该公司出现了几次延误。原型将是一个单通道系统。在我们评估了性能之后，计划是推出更适合临床使用的多通道（4-8通道）系统。有一个后续的三个阶段的项目，以开发一个探测器阵列的剂量引导放射治疗，或DGR。第一阶段是开发一个矩形或螺旋形网格的纤维阵列，并研究放射治疗过程中产生的剂量图以及器官或射束定位的微小变化的影响。阶段II是理解相对于患者的解剖位置的信号变化的含义，并且如果检测到的信号与参考值相差预定的容限，则中断治疗。第三阶段是将网格信号的变化与辐射场的校正变化动态联系起来，以便对辐射治疗进行在线、动态剂量控制。还有一个单独的后续项目，开发一种基于胶片的光释光剂量计，以替代用于剂量测量的照相胶片。初步测量使用地面OSL玻璃分散在薄膜基板上的粘合剂是有前途的，但必须找到更好的方法来生产OSL颗粒的大小均匀。一种可能的方法是采用纳米颗粒掺入OSL分子链，我们目前正在与学术机构合作探索这种可能性。

Phantom studies have been performed. Preliminary studies have been published and a comprehensive assessment of dosimetric parameters is in preparation. The commercial prototype is due to be delivered in mid September for evaluation. There have been several delays at the company due to changes in personnel and shifting priorities. The prototype will be a 1-channel system. After we have assessed performance, the plan is to press for a multichannel (4-8 channels) system that would be more suitable for clinical use. There is a follow-on 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. There is also a separate follow-on 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.