Intraoperative Dose Visualization using X-Ray and Ultrasound for Prostate Brachyt

描述（由申请人提供）：近距离放射治疗广泛用于前列腺癌的管理;美国每年进行超过55，000例手术。近距离放射治疗的流行是由于其微创性和患者的时间承诺。它的成功取决于对前列腺的适当剂量，同时避免对邻近器官的过度辐射。尽管在技术上有一些改进，并从选定的中心发表了优秀的结果，当代多中心报告和质量保证计划文件的结果相当大的变化，随之而来的毒性和次优的结果。公认的不良剂量测定结果的主要贡献者是源定位误差、源可视化差和前列腺水肿，这些因素总体上导致剂量过多和剂量不足的区域。 在手术过程中，对放射源的动态可视化和术中剂量重建的迫切需要得到了广泛的认可。术中剂量优化有望通过允许医生根据个体患者的解剖结构精确调整剂量，以及在手术完成前获得准确的剂量可视化和反馈，从而显著改变近距离放射治疗的护理标准。这需要术中相对于前列腺和周围解剖结构定位植入物。我们建议开发一种临床可行的图像引导平台，能够在近距离放射治疗过程中进行动态，精确和定量的剂量评估。这将允许对源位置改变进行持续校正，并导致最佳植入，从而降低毒性并改善癌症控制。 目标1：动态剂量测定的开发：开发用于术中剂量测定和植入物优化的系统概念和算法。其结果将是一个基于软件的，实用的方法，真正的术中剂量可视化。该系统将不需要对临床硬件进行重大更改，并且将最小限度地改变常规临床工作流程，使其能够广泛使用。 目标二：系统实施和确认：将系统组件技术实施到适合临床使用的近距离放射治疗剂量测定套件中，并在术中评价动态剂量测定系统。将对其在体模中的技术准确性和稳健性进行全面记录和验证，然后进行初步临床研究，以确认系统并评估性能和术中使用的适用性。这些信息将被输入到目标3的系统更新中。 目标3：临床假设和试验：使用单个系统组件进行IRB批准的试验，以及对完全集成的系统进行最终研究，以根据一套严格的基准确定性能，并与当前可用的标准方法进行比较。将获得结局估计值，以便在未来更大规模的II期研究中进行确认。

DESCRIPTION (provided by applicant): Brachytherapy is widely utilized in the management of prostate cancer; over 55,000 procedures are performed in the US annually. The prevalence of brachytherapy is due to its minimally invasive nature and modest time commitment on the part of the patient. Its success hinges on adequately dosing the prostate while avoiding excessive radiation to adjacent organs. Despite some improvements in technique and excellent published results from select centers, contemporary multi-center reports and quality assurance programs document considerable variability in results, with ensuing toxicity and suboptimal outcomes. Well-recognized major contributors to poor dosimetric results are source positioning errors, poor source visualization, and prostatic edema, which in aggregate lead to both regions of excessive as well as inadequate dose. The critical need for dynamic visualization of sources and intraoperative dose reconstruction during the procedure is broadly recognized. Intraoperative dose optimization promises to dramatically change the standard of care in brachytherapy by allowing the physician to precisely tailor the dose to the individual patient's anatomy, as well as obtain accurate dose visualization and feedback prior to procedure completion. This requires intra-operative localization of the implant in relation to the prostate and surrounding anatomy. We propose the development of a clinically feasible image-guidance platform with capability for dynamic, precise and quantitative evaluation of dose during brachytherapy. This will allow for ongoing correction for source position alterations and result in an optimal implant, leading to reduced toxicity and improved cancer control. Aim 1: Development of Dynamic Dosimetry: Develop a system concept and algorithms for intraoperative dosimetry and implant optimization. The result will be a software-based, practical method for true intra-operative dose visualization. The system will not require significant changes in clinical hardware and will minimally alter customary clinical workflow, making it feasible for translation into widespread use. Aim 2: System Implementation and Validation: Perform technical implementation of the system components into a brachytherapy dosimetry suite suitable for clinical use and evaluation of the dynamic dosimetry system intraoperatively. Full documentation and verification of its technical accuracy and robustness in phantoms will be conducted, followed by pilot clinical studies to validate the system and assess performance and suitability for intraoperative use. This information will be fed into system updates for Aim 3. Aim 3: Clinical Hypothesis and Trial: Perform IRB-approved trials utilizing individual system components, as well as a final study of the fully integrated system, in order to establish performance against a rigorous set of benchmarks and to compare with currently available standard methods. Estimates of outcomes will be obtained for confirmation in a future, larger Phase II study.