Fast PET Dosimetry for Proton Therapy

描述（由申请人提供）：美国最近批准的质子治疗报销，创造了质子治疗设施建设的热潮。质子治疗与传统放射治疗（如光子）的区别在于，质子束的布拉格峰以外的组织能够被保留。为了获得最佳剂量，质子布拉格峰的严格耐受性必须与目标的精确定位相匹配，同时确保接受此类治疗的患者数量不断增加。患者数量的增加严重限制了准确定位和固定患者目标的时间。质子治疗的传统剂量学方法（即测量光束电流）不能提供直接的剂量信息，并且产生了对实时直接可视化剂量传递方法的渴望。一些研究者已经提出并实施了体内活化正电子发射化合物的检测，以监测带电粒子治疗（如质子、碳离子）中的剂量递送。自1998年以来，一个双头在线PET相机的原型已经在德国的一家碳治疗机构就位。由于一些技术问题，这一创新并未在其他地方复制，包括图像中的计数统计数据较低，以及安装PET扫描仪以避免干扰光束传输的困难。我们建议采用新的PET检测器配置，提供高计数收集效率和额外的灵活性，为技术人员瞄准质子束。我们的目标是引入在线PET监测的硬件和软件改进，以提高图像质量，并在单次管理期间在线实施纠正策略，以便即时反馈，无论该管理是分割系列的一部分还是单次（即放射手术）。美国最近批准了质子治疗的报销，这使得质子治疗设施的建设蓬勃发展。质子治疗能够比其他方法更紧密地传递放射治疗，因此需要更精确的靶向和监测方法。我们正在建造新的PET扫描仪，它将驻留在质子治疗套件中，并将提供更快速和准确的反馈来指导质子治疗。

DESCRIPTION (provided by applicant): The recent reimbursement approval for proton therapy in the United States has created a boom in construction of proton therapy facilities. Proton therapy is distinguished from conventional (e.g., photon) radiotherapy by the ability to spare tissue beyond the proton beam's Bragg peak. For optimal dosing, the tight tolerances of the proton Bragg peak must be matched by exact localization of targets, while at the same assuring an increasing volume of patients undergoing such procedures. This increased volume of patients threatens to severely constrain the time available to accurately localize and immobilize targets in the patient. Conventional dosimetry approaches to proton therapy (i.e., that measure beam current) do not provide direct information about dose delivered to the tumor, and create a desire for methods of directly visualizing dose delivery in real time. Several investigators have proposed and implemented detection of in vivo activated positron- emitting compounds to monitor dose delivery in charged particle therapy (e.g., protons, carbon ions). A prototype dual-head on-line PET camera has been in place at a carbon therapy facility in Germany since 1998. This innovation has not been duplicated at other sites because of several technical issues, including low count statistics in the image, and difficulties in mounting the PET scanner so that it does not interfere with beam delivery. We propose to employ novel PET detector configurations that provide high count collection efficiency and additional flexibility for the technologist to aim the proton beam. We aim to introduce hardware and software improvements to on-line PET monitoring, in order to improve image quality and to implement a corrective strategy online for immediate feedback during a single administration, whether that administration is part of a fractionated series or is a single- shot (i.e., radiosurgery). PUBLIC HEALTH RELEVANCE: RELEVANCE The recent reimbursement approval for proton therapy in the United States has created a boom in construction of proton therapy facilities. Proton therapy is capable of tighter delivery of radiation therapy than other methods, creating a need for more accurate targeting and monitoring methods. We are building novel PET scanners that will reside in the proton therapy suite, and will which provide more rapid and accurate feedback to guide proton therapy.