TREATMENT UNCERTAINTIES IN THE THORAX & PELVIS--DETECTION, CORRECTION, MODELING

胸部治疗的不确定性

• 批准号: 6237392
• 负责人: GERALD J KUTCHER
• 金额: $ 39.09万
• 依托单位: SLOAN-KETTERING INST CAN RESEARCH
• 依托单位国家: 美国
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-09-01 至 1998-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6237392
• 关键词: artificial intelligence; body movement; clinical research; computed axial tomography; computers; human subject; human therapy evaluation; imaging /visualization /scanning; mathematical model; neoplasm /cancer radiation therapy; radiation therapy dosage

To improve the potential of dose escalation we shall develop methods to deliver dose more precisely, with emphasis on reducing and correcting for organ motion, a principal factor that limits the accurate treatment of the lung and prostate. Since motion in the two sites are caused by different mechanisms, two strategies are proposed. In the lung, the aim is to immobilize the target with deep inspiration breath-hold (DIBH) an dverify its location at each treatment. Thus the high dose volume of normal lung may be minimized due to the reduced apertures an ddecreased lung density. Initially, the effect of respiration on tumor motion will be measured in a cohort of patients with DIBH spiral CT scans, and patient eligibility criteria will be established. Then, we shall develop and implement DIBH treatments with spirometric monitoring of inspiration level. The target positioning will be verified by comparing the location of chest wall and diaphragm on electronic portal images and digitally reconstructed radiographs. The potential benefits will be assessed by comparing treatment plans for DIBH with currently practiced free-breathing treatments. In this pelvis, variability in bladder and rectal filling causesinterfractinal motion. We propose a two-pronged strategy: the patients are planned using the average target position obtained from two or more CT scans, and the aperture margins designed from a generic data set to account for the residual fluctuations of the organs about their mean positions. The generic organ motion data will be measured in a cohort of patients using CT scans acquied at 4 points in time during the treatment course. We shall develop computer tools for optimizing treatment apertures using the generic motion and setup error data, and plan evaluation tools for predicting the variability of dose-volume histograms due to organ motion and setup errors. In addition, we will study CT guided therapy, with a CT scanner located in the treatment room. Patients are scanned prior to treatment, and the target position corrected (if necessary) for the treatment. This task will involve identifying those patients wo have highly mobile prostate by using CT scans acquired prior to or during the early phase of therapy. The initial trial will be on 50 patients for whom the setup is adjusted to register the center-of-mass of the prostate to the isocenter for each treatment fraction. In a later phase, a change in the field shap will also be studied. Finally, the value of such procedures will be assessed with dosimetric studies.

为了提高剂量递增的潜力，我们应开发 更精确地提供剂量的方法，重点是 减少和纠正器官运动，这是导致 限制了肺部和前列腺的准确治疗。 自从 两个部位的运动是由不同的机制引起的，两个 提出了策略。 在肺部，目的是固定 深吸气屏气 (DIBH) 目标并验证其 每次治疗时的位置。因此，正常的高剂量体积 由于孔径减少，肺可能会最小化 d 肺密度降低。 最初，呼吸作用对 将在一组 DIBH 患者中测量肿瘤运动 螺旋 CT 扫描，并将制定患者资格标准。 然后，我们将开发并实施 DIBH 治疗方法 呼吸量监测吸气水平。 目标定位 将通过比较胸壁的位置和 电子门户图像上的隔膜并进行数字重建 放射线照片。 将通过比较来评估潜在的好处 目前采用自由呼吸的 DIBH 治疗计划 治疗。 在这个骨盆中，膀胱和直肠充盈的变化 引起分形运动。 我们提出一个双管齐下的策略： 使用获得的平均目标位置来计划患者 来自两次或多次 CT 扫描，以及设计的孔径裕度 从通用数据集来解释剩余波动 各器官的平均位置。 通用器官运动 将使用 CT 扫描在一组患者中测量数据 在治疗过程中的4个时间点获得。 我们将 开发计算机工具来优化治疗孔径 通用运动和设置误差数据以及计划评估工具 用于预测剂量体积直方图的变异性 器官运动和设置错误。 另外，我们还会学习CT 引导治疗，治疗室设有 CT 扫描仪。 治疗前对患者进行扫描，目标位置 纠正（如有必要）治疗。 这项任务将涉及 通过使用来识别那些患有高度活动性前列腺的患者 在治疗之前或治疗早期期间获得的 CT 扫描。 初步试验将针对 50 名接受该设置的患者进行 调整以将前列腺的质心记录到 每个处理部分的等中心点。 在后期阶段，发生了变化 场形状也将被研究。 最后，这样的价值 程序将通过剂量测定研究进行评估。