Background/Objectives: Stereotactic body radiation therapy (SBRT) for abdominal targets faces a variety of challenges, including motion caused by the respiration and digestion and a relatively poor level of contrast between the tumor and the surrounding tissues. Breath-hold treatments with computed tomography-on-rails (CTOR) image guidance is one way of addressing these challenges, allowing for both the tumor and normal tissues to be well-visualized. Using isodose lines (IDLs) from CT simulations as a guide, the anatomical information can be used to shift the alignment or trigger a replan, such that normal tissues receive acceptable doses of radiation. Methods: This study aims to describe the workflow involved when using CTOR for pancreas and liver SBRT and demonstrates its effectiveness through several case studies. Results: In these case studies, using the anatomical information gained through diagnostic-quality CT guidance to make slight adjustments to the alignment, resulted in reductions in the maximum dose to the stomach. Conclusions: High-quality imaging, such as CTOR, and the use of IDLs to estimate the doses to OARs, enable the safe delivery of SBRT, without the added complexity and resource commitment required by daily online adaptive planning.
背景/目的：针对腹部靶区的立体定向放射治疗（SBRT）面临多种挑战，包括呼吸和消化引起的运动，以及肿瘤与周围组织对比度相对较低。采用导轨计算机断层扫描（CTOR）图像引导下的屏气治疗是应对这些挑战的一种方法，能够清晰显示肿瘤和正常组织。利用CT模拟的等剂量线（IDLs）作为指导，解剖信息可用于调整对齐或触发重新计划，从而使正常组织接受可接受的辐射剂量。方法：本研究旨在描述使用CTOR进行胰腺和肝脏SBRT的工作流程，并通过多个案例研究展示其有效性。结果：在这些案例研究中，利用通过诊断质量CT引导获得的解剖信息对对齐进行微调，降低了胃的最大剂量。结论：高质量成像（如CTOR）以及使用IDLs评估危及器官（OARs）的剂量，能够安全实施SBRT，而无需每日在线自适应计划所需的额外复杂性和资源投入。
肿瘤(癌症)患者之家