Joint Segmentation of MR and CT scans for Gynecologic Cancer Brachytherapy

妇科癌症近距离放射治疗中 MR 和 CT 扫描的联合分割

• 批准号: 8320052
• 负责人: Tina Kapur
• 金额: $ 8.93万
• 依托单位: BRIGHAM AND WOMEN'S HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-08-15 至 2014-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8320052
• 关键词: Algorithms; Anatomic structures; Anesthesia procedures; Appearance; Area; Bladder; Brachytherapy; Brain; Cervix Uteri; Characteristics; Communities; Computer software; Databases; Dose; Female Genital Neoplasms; Film; Funding; Future; Goals; Gray unit of radiation dose; Gynecologic; Gynecologic Brachytherapy; Hospitals; Hour; Image; Image Analysis; Imagery; Joints; Knee; Knowledge; Label; Licensing; Magnetic Resonance Imaging; Malignant Female Reproductive System Neoplasm; Malignant Neoplasms; Malignant neoplasm of cervix uteri; Methods; Modality; Noise; Normal tissue morphology; Operating Rooms; Organ; Patients; Pelvis; Positioning Attribute; Probability; Procedures; Process; Prospective Studies; Radiation; Radiation Oncologist; Radiation Oncology; Radiation therapy; Radioisotopes; Rectum; Relative (related person); Research; Research Project Grants; Risk; Scanning; Sigmoid colon; Signal Transduction; Small Intestines; Structure; Techniques; Testing; Therapeutic Studies; Three-Dimensional Image; Tissues; Toxic effect; Translating; Vagina; Validation; Variant; Work; X-Ray Computed Tomography; design; expectation; human female; image registration; imaging Segmentation; imaging modality; improved; infancy; killings; neoplastic cell; open source; spatial relationship; treatment planning; tumor

DESCRIPTION (provided by applicant): The placement of radioactive isotopes directly into a cancer of the uterine cervix or vagina in order to eradicate the cancer, requires insertion of a hollow applicator into the tumor. Though previously plain x-ray film depicted the position of the applicator, and was used to calculate the dose to deliver to an area around the applicator, 3D CT revolutionized tumor visualization in the 1990s. However, MRI more clearly defines gynecologic tumors, though the application of MRI to gynecologic brachytherapy is in its infancy. Research in the last five years has shown that using CT alone overestimates the extent of normal tissue that surrounds the cancer compared to MR. In comparison MR allows the radiation oncologist to draw tighter boundaries around the target volume that should receive the highest radiation dose, while sparing larger amounts of surrounding normal tissue. Current practice at our hospital after applicator insertion in the operating room is to obtain a 3D image to guide radiation treatment planning. Patients with large tumors undergo both a CT and an MRI. Commercial software aligns the MRI and CT to each other, and is used to outline target cancer and surrounding organs at risk. A treatment plan is generated and radiation is delivered to the patient using this plan. Current alignment and contouring methods require significant expert input from the radiation oncologist and physicist while the patient waits for treatment under anesthesia. This project will improve the efficiency of this workflow using advanced image analysis methods as follows. 1) We will develop an EM-ESP segmenter to simultaneously segment registered MR and CT scans for gynecologic brachytherapy planning. This segmenter will construct and use joint prior probability distributions on image intensities and the geometry of key anatomic structures relative to the brachytherapy applicator, which is clearly visible in the images. 2) We will apply the EM-ESP segmenter retrospectively on a database of 25 patients who were treated during 2004-2006 using MR guided brachytherapy by Dr. Akila Viswanathan, Chief of Gynecologic Radiation Oncology at our hospital. Contours were drawn manually on these scans, and we will test our method against these. The result of this project will be an algorithm that can automatically delineate the cervix, the bladder, the rectum, the sigmoid colon, and the small bowel in MR and CT images for gynecologic brachytherapy. To the best of our knowledge, the proposed algorithm will be the first to provide this functionality. ( ( !

描述（由申请人提供）：将放射性同位素直接放入子宫颈或阴道的癌症中以根除癌症，需要将中空施药器插入肿瘤中。虽然以前的普通 X 射线胶片描绘了施放器的位置，并用于计算递送到施放器周围区域的剂量，但 3D CT 在 20 世纪 90 年代彻底改变了肿瘤可视化。然而，尽管 MRI 在妇科近距离放射治疗中的应用还处于起步阶段，但 MRI 可以更清晰地定义妇科肿瘤。过去五年的研究表明，与 MR 相比，单独使用 CT 会高估癌症周围正常组织的范围。相比之下，MR 允许放射肿瘤学家在应接受最高辐射剂量的目标体积周围划定更严格的边界，同时保留大量周围的正常组织。我们医院目前的做法是在手术室插入施源器后获取 3D 图像来指导放射治疗计划。肿瘤较大的患者需接受 CT 和 MRI 检查。商业软件将 MRI 和 CT 相互对齐，用于勾勒出目标癌症和周围有风险的器官。制定治疗计划并使用该计划向患者进行放射治疗。当前的对准和轮廓方法需要放射肿瘤学家和物理学家在患者在麻醉下等待治疗时提供重要的专家输入。该项目将使用以下先进的图像分析方法来提高该工作流程的效率。 1) 我们将开发一种 EM-ESP 分段器，以同时分段注册的 MR 和 CT 扫描，用于妇科近距离放射治疗计划。该分割器将构建并使用图像强度的联合先验概率分布以及相对于近距离放射治疗施用器的关键解剖结构的几何形状，这在图像中清晰可见。 2) 我们将回顾性地将 EM-ESP 分段器应用于 25 名患者的数据库，这些患者在 2004 年至 2006 年期间使用我们医院妇科放射肿瘤科主任 Akila Viswanathan 博士使用 MR 引导近距离放射治疗进行治疗。在这些扫描上手动绘制轮廓，我们将针对这些扫描来测试我们的方法。该项目的成果将是一种算法，可以在妇科近距离放射治疗的 MR 和 CT 图像中自动描绘子宫颈、膀胱、直肠、乙状结肠和小肠。据我们所知，所提出的算法将是第一个提供此功能的算法。 （（！