CT Image Estimation for Calculation of Delivered Dose

描述(申请人提供)：前列腺是一种可移动的器官，它展示了位置和形状的瞬间和每日变化，这些变化对放射治疗的准确提供具有至关重要的影响。因此，在现代前列腺癌放射治疗中，标准做法是在大多数时间内定位前列腺，作为辅助治疗，以实现在保护附近对辐射敏感的正常组织的同时向前列腺输送高剂量的目标。第一阶段研究确定了一种新方法的可行性，该方法使用一类统计可训练变形形状模型的独特数学特性，通过基于在前列腺中植入的标记的测量位置将参考CT图像数据映射到治疗空间来估计治疗图像数据。估计的图像捕捉治疗期间前列腺的姿势、位置和形状，适用于准确计算传输到前列腺及其周围组织的剂量。这项第二阶段研究的头两年将专注于基于这一创新技术的临床原型系统的设计和开发。该原型将在第三年的临床环境中进行评估。设想的商业表单将接受来自包括治疗计划系统、治疗机和标记跟踪系统的多个设备的输入数据，并将输出数据传送到治疗计划系统。在几秒钟内，拟议的原型将使用输入数据来自动计算估计的治疗图像和计算提供的剂量。拟议的系统将利用目前正在进行的第二阶段项目(R44 CA119571)下完成的工作，该项目将允许原型与治疗内成像设备以及标记追踪器一起使用。此外，建议的方法可以实现一种形式的剂量计算，称为同步动态剂量重建，这是最准确的ART形式所需的。 与公共卫生相关：前列腺是一个可移动的器官，它显示出位置和形状的瞬间和每日变化，这些变化对准确提供放射治疗具有至关重要的影响。因此，在现代前列腺癌放射治疗中，标准做法是在大多数时间内定位前列腺，作为辅助治疗，以实现在保护附近对辐射敏感的正常组织的同时向前列腺输送高剂量的目标。第一阶段研究确定了一种新方法的可行性，该方法使用一类统计可训练变形形状模型的独特数学特性，通过基于在前列腺中植入的标记的测量位置将参考CT图像数据映射到治疗空间来估计治疗图像数据。估计的图像捕捉治疗期间前列腺的姿势、位置和形状，适用于准确计算传输到前列腺及其周围组织的剂量。这项第二阶段研究的头两年将专注于基于这一创新技术的临床原型系统的设计和开发。该原型将在第三年的临床环境中进行评估。设想的商业表单将接受来自包括治疗计划系统、治疗机和标记跟踪系统的多个设备的输入数据，并将输出数据传送到治疗计划系统。在几秒钟内，拟议的原型将使用输入数据来自动计算估计的治疗图像和计算提供的剂量。拟议的系统将利用目前正在进行的第二阶段项目(R44 CA119571)下完成的工作，该项目将允许原型与治疗内成像设备以及标记追踪器一起使用。此外，建议的方法可以实现一种形式的剂量计算，称为同步动态剂量重建，这是最准确的ART形式所需的。该项目将以两种方式促进公共卫生：1)它将允许一种名为自适应放射规划的治疗内图像指导形式的治疗规划，确保计划剂量与实际提供剂量之间的密切匹配；2)它将提供必要的、但目前缺乏的质量保证步骤，以确认每一次治疗过程中提供剂量的安全性。鉴于最近发生的一系列虐待事件，许多人认为新的规划和交付技术已经超过了独立验证安全规划和交付的临床实用方法的发展，这一贡献尤其重要。

DESCRIPTION (provided by applicant): The prostate is a mobile organ that demonstrates momentary and daily changes in position and shape that critically affect accurate delivery of radiation therapy. For this reason, in modern technically demanding radiation therapy for prostate cancer, it is standard practice to localize the prostate on most days treatment as an aid to achieve the goal of delivering a high dose to the prostate while protecting nearby radiosensitive normal tissues. The Phase I study established the feasibility of a novel approach that uses unique mathematical properties of a class of statistically trainable deformable shape models to estimate treatment image data by mapping reference CT image data into the treatment space based on measured positions of markers implanted in the prostate. The estimated images capture the pose, position and shape of the prostate during treatment and are suitable for accurate calculation of dose delivered to the prostate and immediately surrounding tissues. The first two years of this Phase II study will focus on design and development of a clinical prototype system based on this creative technology. The prototype will be evaluated in the clinical setting during the third year. The envisioned commercial form will accept input data from multiple devices including the treatment planning system, treatment machine, and marker tracking system, and will communicate output data to the treatment planning system. Within a few seconds the proposed prototype will use input data to automatically compute the estimated treatment image and calculate delivered dose. The proposed system will leverage work accomplished under a currently active Phase II project (R44 CA119571) that will allow the prototype to be used with intra-treatment imaging devices as well as marker-trackers. Moreover the proposed approach may enable a form of dose computation, called synchronized dynamic dose reconstruction, needed for the most accurate form of ART. PUBLIC HEALTH RELEVANCE: The prostate is a mobile organ that demonstrates momentary and daily changes in position and shape that critically affect accurate delivery of radiation therapy. For this reason, in modern technically demanding radiation therapy for prostate cancer, it is standard practice to localize the prostate on most days treatment as an aid to achieve the goal of delivering a high dose to the prostate while protecting nearby radiosensitive normal tissues. The Phase I study established the feasibility of a novel approach that uses unique mathematical properties of a class of statistically trainable deformable shape models to estimate treatment image data by mapping reference CT image data into the treatment space based on measured positions of markers implanted in the prostate. The estimated images capture the pose, position and shape of the prostate during treatment and are suitable for accurate calculation of dose delivered to the prostate and immediately surrounding tissues. The first two years of this Phase II study will focus on design and development of a clinical prototype system based on this creative technology. The prototype will be evaluated in the clinical setting during the third year. The envisioned commercial form will accept input data from multiple devices including the treatment planning system, treatment machine, and marker tracking system, and will communicate output data to the treatment planning system. Within a few seconds the proposed prototype will use input data to automatically compute the estimated treatment image and calculate delivered dose. The proposed system will leverage work accomplished under a currently active Phase II project (R44 CA119571) that will allow the prototype to be used with intra-treatment imaging devices as well as marker-trackers. Moreover the proposed approach may enable a form of dose computation, called synchronized dynamic dose reconstruction, needed for the most accurate form of ART. This project will contribute to public health in two ways: 1) It will allow an intra-treatment-image-guided form of treatment planning called Adaptive Radiation Planning that assures a close match between the planned and actual delivered doses; and 2) It will provide a needed but currently missing quality assurance step to confirm the safety of the delivered dose for each treatment session. This contribution is especially significant in light of a series of recent mistreatments that have led many to believe that new planning and delivery technologies have outpaced the development of clinically practical methods to independently validate safe planning and delivery.