Integrated Photoacoustic Ultrasound Real-time Imaging for Brachytherapy Treatment

描述（由申请人提供）：前列腺癌影响每六名男性中的一名，并且仍然是男性癌症相关死亡的第二大原因。永久性组织间近距离放射治疗，即在前列腺中永久放置放射性粒子，广泛用于治疗前列腺癌。尽管最近机器人手术（报告泌尿系统发病率增加）对近距离放射治疗和传统手术都产生了影响，但近距离放射治疗仍然是一种广泛使用的治疗方法。从历史的角度来看，近距离放射治疗是一种具有潜在良好长期结果的明确治疗选择。近距离放射治疗的成功取决于充分照射前列腺，同时避免对周围器官的过度辐射，最重要的是尿道和直肠。尽管近距离放射治疗技术的改进改善了结局，但当代报告记录了近距离放射治疗实践的相当大的变化，导致次优结局和毒性。公认的导致这些不良结局的主要因素是缺乏真实的实时图像引导，以在术中可视化源放置和剂量，因为它由于种子定位误差和前列腺水肿的发生而演变。所提出的工作是在智能平台上开发一种多模态图像引导，该平台具有实时，精确， 以及在近距离放射治疗过程中对源位置和目标剂量测定的定量评估，从而允许医生连续地校正源位置改变并自适应地实现最佳植入，从而导致降低的毒性和改善的癌症控制。 拟议的工作是开发，设计和评价的实时成像系统的基础上集成的光声和经直肠超声图像引导和先进的图像处理软件，将产生实时，精确和定量评价的种子位置和剂量在近距离放射治疗过程中，同时可视化前列腺解剖结构。所提出的系统将集成成像和规划工具，这些工具已经在当前的近距离放射治疗实践中常规使用，并包含低成本的激光源。实时成像将使医生能够连续校正源位置误差，并在不中断现有手术工作流程的情况下自适应地实现最佳植入，从而降低毒性并改善癌症控制。 该研究计划将在三个目标中进行：1）研究前列腺和金属种子的光学特性，2）开发集成的光声和经直肠超声成像系统，3）在组织模拟体模、离体前列腺和有限的体内动物研究中进行系统集成、测试和验证。所提出的集成系统将是第一个具有近距离放射治疗植入物实时成像能力并同时可视化前列腺解剖结构的系统。

DESCRIPTION (provided by applicant): Prostate cancer affects one in every six men and remains the second leading cause of cancer related mortality in men. Permanent interstitial brachytherapy, the permanent placement of radioactive seeds in the prostate, is widely used in the treatment of prostate cancer. Despite the recent uptake in robotic surgery (with reported increased urinary morbidity) which has impacted both brachytherapy and conventional surgery, brachytherapy remains a widely used treatment. In the historical perspective, brachytherapy has been a definitive treatment option with potentially excellent long term results. The success of brachytherapy depends on adequately irradiating the prostate while avoiding excessive radiation to surrounding organs, most importantly the urethra and rectum. Despite improved outcomes from modifications in brachytherapy technique, contemporary reports document considerable variability in brachytherapy practice, with resultant suboptimal outcomes and toxicity. A recognized major contributor to these poor outcomes is the lack of real- time image guidance to visualize source placement and dose intra-operatively as it evolves due to seed positioning errors and the onset of prostatic edema. The proposed work is the development of a multi-modal image-guidance build in an intelligent platform with capability for real-time, precise, and quantitative evaluation of source position and target dosimetry during the course of a brachytherapy procedure, thereby allowing the physician to continuously correct for source position alterations and adaptively achieve an optimal implant, resulting in both reduced toxicity and improved cancer control. The proposed work is the development, design and evaluation of a real-time imaging system based on integrated photo-acoustic and transrectal ultrasound image guidance and advanced image processing software that will produce real-time, precise, and quantitative evaluation of seed positions and dosimetry during the brachytherapy procedure and visualize prostate anatomy simultaneously. The proposed system will integrate imaging and planning tools that are already routinely used in current brachytherapy practice with an inclusion of low cost laser source. The real-time imaging will enable the physician to continuously correct for source position errors and adaptively achieve an optimal implant without disruption of existing surgical workflow, resulting in both reduced toxicity and improved cancer control. The research plan will be carried out in three aims: 1) study the optical properties of both prostate and metallic seed, 2) develop integrated photo-acoustic and transrectal ultrasound imaging system, and 3) perform system integration, testing and validation in tissue-mimicking phantoms, ex vivo prostrates and a limited in vivo animal study. The proposed integrated system will be first of its kind to have the capability of real-time imaging of brachytherapy implant and simultaneously visualizing prostate anatomy.