Coded-aperture Compton scatter imaging for real-time tumor motion tracking during ablative radiotherapy

编码孔径康普顿散射成像用于消融放射治疗期间实时肿瘤运动跟踪

• 批准号: 10308727
• 负责人: Bernard L Jones
• 金额: $ 14.01万
• 依托单位: UNIVERSITY OF COLORADO DENVER
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-12-01 至 2024-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10308727
• 关键词: Abdomen; Astronomy; Breathing; Clinical; Clinical Trials; Code; Compton radiation; Databases; Discipline of Nuclear Medicine; Dose; Dose-Limiting; Equipment; Future; Goals; Gold; Guidelines; Image; Implant; Linear Accelerator Radiotherapy Systems; Liver; Liver neoplasms; Local Therapy; Location; Magnetic Resonance Imaging; Measurement; Measures; Melanoma Cell; Methods; Modernization; Motion; Non-Small-Cell Lung Carcinoma; Normal tissue morphology; Pancreas; Pancreatic Adenocarcinoma; Patient-Focused Outcomes; Patients; Performance; Photons; Positioning Attribute; Radiation Dose Unit; Radiation Scattering; Radiation therapy; Renal Cell Carcinoma; Resolution; Roentgen Rays; Signal Transduction; Source; Syncope; System; Techniques; Testing; Therapeutic; Time; Toxic effect; Work; base; cost; design; detector; effective therapy; image guided; image guided radiation therapy; imager; imaging properties; imaging system; improved; improved outcome; lung cancer cell; novel; pancreatic neoplasm; pilot trial; programs; prototype; real-time images; side effect; tumor

Project Summary/Abstract Stereotactic Body Radiation Therapy (SBRT) is an aggressive, ablative local therapy that can be an effective treatment for many hard-to-treat tumors, such as pancreatic adenocarcinoma, non-small cell lung cancer, melanoma, and renal cell carcinoma. By delivering large, ablative doses of radiation in a small number of treatments, SBRT leads to significantly improved local control. However, there is a trade-off between delivering aggressive doses of radiation in the abdomen with SBRT and dose-limiting side-effects. A major problem is that the breathing-induced motion of the abdomen is erratic and unstable, rendering traditional methods of motion management ineffective. To enable safe and effective dose escalation for these tumors, we are proposing a novel imaging system that measures the position of fiducial markers implanted inside the patient. This system, called Coded Aperture Scatter Imaging (CASI), passively measures the position of tumors during treatment with no additional radiation dose. During radiotherapy, a beam of megavoltage x-rays is directed towards the tumor, and some of those photons undergo scattering interactions within the patient. These photons are more likely to interact in the dense, high-atomic-number fiducial markers, providing a differential signal that can be measured by an imager placed orthogonal to the beam. We propose to use coded aperture imaging to decode the location of these fiducial markers in real time. The coded aperture technique, utilized in fields such as astronomy and nuclear medicine, can help identify faint point sources within a broad background. CASI is clinically attractive for several reasons. This passive technique provides real-time motion information with no additional imaging dose, since it forms an image using scattered photons from the treatment beam. CASI is easily implementable on any existing clinical linear accelerator, since all modern linacs are equipped with a kV imaging panel placed orthogonal to the treatment beam. Fiducial markers are commonly implanted in these tumors, and the only additional hardware needed is the coded aperture itself, which can simply be placed between the patient and the detector. Finally, by measuring the motion of tumors during treatment one could increase the accuracy of treatment delivery, which could enable more effective, dose-escalated treatments that avoid toxicity to normal tissues. The goal of this work is to design, fabricate, and test an optimized aperture for CASI-guided radiotherapy.

项目摘要/摘要 立体定向的身体放射疗法（SBRT）是一种侵略性的，消融的局部疗法，可以是一种 有效治疗许多难以治疗的肿瘤，例如胰腺腺癌，非小细胞肺 癌症，黑色素瘤和肾细胞癌。通过在少数数字中输送大量的散热剂量 在治疗中，SBRT导致显着改善了局部控制。但是，在 用SBRT和剂量限制副作用在腹部中提供侵略性剂量的辐射。专业 问题是腹部的呼吸引起的运动是不稳定且不稳定的，传统 运动管理方法无效。 为了实现这些肿瘤的安全有效剂量升级，我们提出了一个新型的成像系统 这可以衡量植入患者内部的基准标记的位置。该系统称为编码光圈 散射成像（CASI），被动测量治疗过程中肿瘤的位置，没有其他 辐射剂量。在放疗过程中，一束巨型X射线射线朝向肿瘤，其中一些 这些光子在患者内经历散射相互作用。这些光子更有可能在 致密的高原子数标记物，提供了一个差异信号，可以通过 成像仪将正交放在光束上。我们建议使用编码的孔径成像来解码 这些基准标记是实时的。编码的孔径技术，用于天文学和诸如天文学的领域 核医学可以帮助识别广泛背景中的微弱点源。 CASI在临床上很有吸引力，原因有几个。这种被动技术提供实时运动 没有其他成像剂量的信息，因为它使用来自散射的光子形成图像 处理梁。 CASI易于在任何现有的临床线性加速器上实现，因为所有现代 Linacs配备了一个KV成像面板，放置在治疗梁上。基准标记是 通常植入这些肿瘤，唯一需要的其他硬件是编码孔本身， 可以简单地放置在患者和检测器之间。最后，通过测量肿瘤的运动 在治疗过程中，可以提高治疗递送的准确性，这可以使得更有效， 剂量提出的治疗方法避免了对正常组织的毒性。这项工作的目的是设计，制造， 并测试优化的光圈进行CASI引导的放射疗法。