Radiation Medicine Program, Princess Margaret Hospital, University of Toronto Faculty of Medicine, Toronto, ON, Canada.
Int J Radiat Oncol Biol Phys. 2011 Feb 1;79(2):602-8. doi: 10.1016/j.ijrobp.2010.04.028. Epub 2010 Aug 1.
Abdominal compression (AC) can be used to reduce respiratory liver motion in patients undergoing liver stereotactic body radiotherapy. The purpose of the present study was to measure the changes in three-dimensional liver tumor motion with and without compression using cine-magnetic resonance imaging.
A total of 60 patients treated as a part of an institutional research ethics board-approved liver stereotactic body radiotherapy protocol underwent cine T2-weighted magnetic resonance imaging through the tumor centroid in the coronal and sagittal planes. A total of 240 cine-magnetic resonance imaging sequences acquired at one to three images each second for 30-60 s were evaluated using an in-house-developed template matching tool (based on the coefficient correlation) to measure the magnitude of the tumor motion. The average tumor edge displacements were used to determine the magnitude of changes in the caudal-cranial (CC) and anteroposterior (AP) directions, with and without AC.
The mean tumor motion without AC of 11.7 mm (range, 4.8-23.3) in the CC direction was reduced to 9.4 mm (range, 1.6-23.4) with AC. The tumor motion was reduced in both directions (CC and AP) in 52% of the patients and in a single direction (CC or AP) in 90% of the patients. The mean decrease in tumor motion with AC was 2.3 and 0.6 mm in the CC and AP direction, respectively. Increased motion occurred in one or more directions in 28% of patients. Clinically significant (>3 mm) decreases were observed in 40% and increases in <2% of patients in the CC direction.
AC can significantly reduce three-dimensional liver tumor motion in most patients, although the magnitude of the reduction was smaller than previously reported.
腹部压迫（AC）可用于减少行肝脏立体定向体部放射治疗的患者的呼吸性肝脏运动。本研究的目的是使用电影磁共振成像测量有和无压迫时三维肝肿瘤运动的变化。
总共 60 名作为机构研究伦理委员会批准的肝脏立体定向体部放射治疗方案的一部分的患者在冠状面和矢状面通过肿瘤中心点进行电影 T2 加权磁共振成像。使用内部开发的模板匹配工具（基于系数相关）评估总共 240 个每秒一到三个图像的电影磁共振成像序列 30-60 秒，以测量肿瘤运动的幅度。使用平均肿瘤边缘位移来确定有无 AC 时的头脚（CC）和前后（AP）方向的变化幅度。
无 AC 时的平均肿瘤运动为 11.7 毫米（范围，4.8-23.3），在 CC 方向上减少到 9.4 毫米（范围，1.6-23.4）。在 52%的患者中，肿瘤运动在两个方向（CC 和 AP）上减少，在 90%的患者中仅在一个方向（CC 或 AP）上减少。AC 时肿瘤运动的平均减少幅度分别为 CC 和 AP 方向的 2.3 和 0.6 毫米。在 28%的患者中，一个或多个方向出现运动增加。在 CC 方向，观察到 40%的患者有临床显著（>3 毫米）减少，<2%的患者增加。
AC 可显著减少大多数患者的三维肝肿瘤运动，尽管减少幅度小于先前报道。
