Mannerberg Annika, Nilsson Martin P, Edvardsson Anneli, Karlsson Kristin, Ceberg Sofie
Medical Radiation Physics, Department of Clinical Sciences Lund, Lund University, Lund, Sweden.
Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden.
Phys Imaging Radiat Oncol. 2023 Oct 7;28:100499. doi: 10.1016/j.phro.2023.100499. eCollection 2023 Oct.
Stereotactic body radiotherapy (SBRT) has emerged as a promising treatment for patients with ventricular tachycardia (VT) who do not respond to standard treatments. However, the management of respiratory motion during treatment remains a challenge. This study aimed to investigate the effect of abdominal compression (AC) on respiratory induced motion in the heart.
A patient cohort of 18 lung cancer patients was utilized, where two four-dimensional computed tomography (4DCT) scans were performed for each patient, one with and one without AC. The patient setup consisted of an AC plate together with a stereotactic body frame. The left coronary artery, the left anterior descending artery, the lateral wall of the left ventricle, the heart apex, the carina, and the right and left diaphragm were delineated in max expiration and max inspiration phases in both 4DCT scans. The center of mass shift from expiration to inspiration phase was determined to assess the AC's impact on respiratory motion.
A significant reduction in motion in the superior-inferior direction was found for all heart structures when AC was used. The median respiratory motion of the heart structures decreased by approximately 1-3 mm with AC in the superior-inferior direction, and approximately 60% of the patients had a motion reduction ≥3 mm in the left ventricle wall.
These findings suggest that AC has the potential to improve the motion management of SBRT for VT patients, by reducing the respiratory induced motion in the heart.
立体定向体部放疗（SBRT）已成为对标准治疗无反应的室性心动过速（VT）患者的一种有前景的治疗方法。然而，治疗期间呼吸运动的管理仍然是一项挑战。本研究旨在探讨腹部压迫（AC）对心脏呼吸诱发运动的影响。
使用了一个由18名肺癌患者组成的队列，每位患者进行两次四维计算机断层扫描（4DCT），一次有AC，一次无AC。患者体位由一块AC板和一个立体定向体架组成。在两次4DCT扫描的最大呼气和最大吸气阶段，勾画出左冠状动脉、左前降支动脉、左心室侧壁、心尖、隆突以及左右膈肌。确定从呼气到吸气阶段的质心移位，以评估AC对呼吸运动的影响。
使用AC时，所有心脏结构在上下方向的运动均显著减少。心脏结构在上下方向上的中位呼吸运动在使用AC时减少了约1 - 3毫米，约60%的患者左心室壁运动减少≥3毫米。
这些发现表明，AC有可能通过减少心脏的呼吸诱发运动来改善VT患者SBRT的运动管理。
