Real-time Image Registration for 3-D Ultrasound Guided Partial Breast Irradiation

描述（由申请人提供）：乳腺癌是美国女性最常见的恶性肿瘤。据估计，每年有225,000例新的乳腺癌被诊断出来。体外束部分乳房照射（EB-PBI）是一种无创、高效、经济的I期和II期乳腺癌放射治疗模式。然而，EB-PBI的治疗质量由于治疗计划中靶体积的不准确和治疗过程中乳房肿瘤切除腔和乳房变形而受到靶位置不准确的影响。机载治疗乳房图像目前可通过容积式乳房超声扫描仪（VBUS）进入我们研究所现有的EB-PBI。本课题的目的是开发一种实时图像配准工具，将规划的CT图像自动配准到规划或治疗中的三维超声乳房图像。我们计划验证以下假设：1)实时可变形图像配准（DIR）算法的实施将使我们能够在治疗过程中模拟乳房和乳房肿瘤切除腔的变形；2)这个新开发的计算工具将使我们能够根据最新的患者解剖结构优化治疗计划，从而提高给药剂量的精度和保留辅助正常组织。我们的具体目标和可测量目标是：1)开发基于gpu的超快速图像配准工具，用于超声和CT图像配准；2)通过对一系列数字幻影、实验幻影和真实患者数据集的顺序测试，对所开发的配准工具进行验证和评估；3)证明实时图像配准工具的开发将实现精确的目标定位和最佳剂量分布。该项目的成功将提供一种利用机载治疗超声图像高效准确定位治疗靶体积的方法。因此，它将提高乳腺癌患者护理的治疗质量，提高治疗的准确性，同时保留邻近的健康组织。此外，在这项工作中开发的一般方法对乳腺癌以外的各种癌症的放射治疗具有广泛的适用性。

DESCRIPTION (provided by applicant): Breast cancer is the most common malignancy of women in the USA. It is estimated that 225,000 new breast cancers are diagnosed every year. External beam partial breast irradiation (EB-PBI) is a non-invasive, time- efficient and cost-effective radiation therapy treatment paradigm for stage I and II breast cancer. However, the treatment quality of EB-PBI suffers from inaccurate target location due to the misrepresentation of target volume during treatment planning and lumpectomy cavity and breast deformation during the treatment course. Onboard treatment breast image is currently available by integer a volumetric breast ultrasound scanner (VBUS) into the existing EB-PBI in our institute. The object of this project is to develop a real-time image registration tool to automatically register the planning computed tomography (CT) image to the planning or on- treatment 3-D ultrasound breast image. We plan to test the hypothesis that 1) the implementation of the real- time deformable image registration (DIR) algorithm will enable us to model the breast and lumpectomy cavity deformation as treatment progresses and 2) this new developed computational tool will permit us to improve the precision of delivery dose and sparing of adjunct normal tissue by optimizing the treatment plan in accordant with up-to-date patient anatomy. Our specific aims and measurable objectives are: 1) to develop a GPU-based ultrafast image registration tool for ultrasound and CT images registration; 2) to validate and assess the developed registration tool by sequentially testing on series of digital phantoms, experimental phantoms, and real patients' data sets; 3) to demonstrate that development of the real-time image registration tool will enable precise target location and optimal dose distribution. The success of the proposed project will provide a method that utilizes on-board treatment ultrasound images to locate treatment target volume in an efficient and accurate way. Consequently it will enhance the therapeutic quality of breast cancer patient care by improving the precision of treatment delivery while sparing adjacent healthy tissues. Additionally, the general methodology developed in this work has a broad applicability to the radiation therapy of a variety of cancers other than breast cancer. PUBLIC HEALTH RELEVANCE: This project is to innovatively incorporate the 3-D ultrasound breast imaging technique into the online adaptive breast radiotherapy system through developing a real-time image registration computational tool. This online adaptive breast radiotherapy paradigm will substantially improve the therapeutic quality of breast cancer patient care by precisely locating target volume and optimally compensating for breast anatomy changes.