Robotic SPECT for Biological Imaging Onboard Radiation Therapy Machines

描述(申请人提供)：该项目广泛的长期目标是在放射治疗机上提供生物成像-即癌症患者处于治疗位置时的生物成像。目前的星载目标定位主要基于X射线透射式成像，对生物学不敏感，无法识别部分肿瘤。除了靶点定位外，还提出了根据生物功能(如缺氧)来调整剂量。机载生物成像--用于这些任务--可以通过单光子发射计算机断层扫描(SPECT)提供。SPECT在肿瘤相关生物学方面的能力正在迅速发展，如缺氧、血管生成、细胞增殖、代谢、表皮生长因子受体、细胞凋亡和多药耐药。低成本的SPECT可以被设计到放射治疗室。SPECT示踪器广泛可用，双示踪剂SPECT成像是可能的，SPECT系统有可能对F-18等正电子发射体成像。机载SPECT的任务是在一个小体积内定位生物功能，该体积的大致位置可以通过其他定位程序知道。实现机载SPECT受到时间限制(d 5分钟)和治疗室几何约束的挑战。将开发新的SPECT方法来应对这些任务和挑战。其目标是：(1)开发一个原型系统--由一个紧凑的核医学探测器和一个机械臂组成--它可以操纵探测器围绕处于放射治疗位置的患者。(2)设计了有限体积的机载平行孔和针孔SPECT成像轨迹，并利用机器人/探测器系统对这些轨迹的任务性能进行了评估。这些目标涉及不仅对机载SPECT而且对总体SPECT都很重要的技术发展。AIM(1)能够实现常规SPECT机架无法实现的探测器轨迹。目的(2)开发和探索新的探测器轨迹和新硬件实施它们的能力。这项工作将推动SPECT朝着新的方向发展，使放射治疗中的实时生物靶向成为可能，并有可能改善治疗结果。 与公共健康相关：板载SPECT可以在患者接受放射治疗时提供肿瘤生物学的三维图像，从而允许基于肿瘤生物学的放射治疗光束实时对准。这有望改善肿瘤控制和健康组织保存。

DESCRIPTION (provided by applicant): The broad long-term objective of this project is to provide biological imaging onboard radiation treatment machines - that is, biological imaging as the cancer patient is in treatment position. Current onboard target localization is based mainly on x-ray transmission imaging, which is not sensitive to biology and cannot identify some tumors. In addition to target localization, it has also been proposed that dose be modified based on biological function such as hypoxia. Onboard biological imaging - for these tasks - could be provided by single-photon emission computed tomography (SPECT). SPECT is evolving rapidly in its ability to image cancer-relevant biology, such as hypoxia, angiogenesis, cell proliferation, metabolism, epidermal growth factor receptor, apoptosis, and multi-drug resistance. Low-cost SPECT can be engineered to the radiation treatment room. SPECT tracers are widely available, dual-tracer SPECT imaging is possible, and SPECT systems have potential to image positron emitters such as F-18. The onboard SPECT task is to localize biological function within a small volume whose approximate location is known by other localization procedures. Realization of onboard SPECT is challenged by limited time (d 5 minutes) and by geometrical constraints of the treatment room. Novel SPECT methods will be developed to address these tasks and challenges. The Aims are: (1) Develop a prototype system - comprised of a compact nuclear-medicine detector and a robotic arm - that can maneuver the detector about a patient in position for radiation therapy. (2) Design trajectories for onboard parallel-hole and pinhole SPECT imaging of limited volumes, and use the robot/detector system to evaluate task performance of these trajectories. These Aims involve technological developments important not only for onboard SPECT but for SPECT generally. Aim (1) enables detector trajectories that are not possible with conventional SPECT gantries. Aim (2) develops and explores new detector trajectories and the ability of the new hardware to implement them. This work will advance SPECT in novel directions, allowing real-time biological targeting in radiation therapy, and potentially improving treatment outcome. PUBLIC HEALTH RELEVANCE: Onboard SPECT can be developed to provide three-dimensional images of tumor biology while the patient is on the radiation therapy treatment table, allowing real-time alignment of the radiation therapy beam based on tumor biology. This is expected to improve tumor control and healthy tissue sparing.