Department of Radiology, University of Michigan, Ann Arbor, Michigan, USA.
J Ultrasound Med. 2012 Mar;31(3):469-81. doi: 10.7863/jum.2012.31.3.469.
We prospectively evaluated real-time ultrasound speckle tracking for monitoring soft tissue motion for image-guided radiotherapy. Two human volunteers and 1 patient with a proven hepatocellular carcinoma, who was being prepared for radiation therapy treatment, were scanned using a clinical ultrasound scanner modified to acquire and store radiofrequency signals. Scans were performed of the liver in the volunteers and the patient. In the patient, the speckle-tracking results were compared to those measured on a treatment-planning 4-dimensional computed tomogram with tumors contoured manually in each phase and with estimates made by hand on gray scale ultrasound images. The surface of the right lung and the prostate were scanned in a volunteer. The liver and lung surface were scanned during respiration. To simulate prostate motion, the ultrasound probe was rocked in an anterior-posterior direction. The correlation coefficients of all motion measurements were significantly correlated at all sites (P < .00001 for all sites) with 0 time delays. Ultrasound speckle-tracking motion estimates of tumor motion were within 2 mm of estimates made by hand tracking on gray scale ultrasound images and the 4-dimensional computed tomogram. The total tumor motion was greater than 20 mm. The angular displacement of the prostate was within 0.02 radians (1.1°) with displacements measured by hand. Speckle tracking could be used to monitor organ motion during radiotherapy.
我们前瞻性地评估了实时超声斑点跟踪技术，以监测图像引导放射治疗中的软组织运动。使用经过修改的临床超声扫描仪对 2 名人类志愿者和 1 名经证实患有肝细胞癌的患者进行了扫描，该扫描仪可以采集和存储射频信号。对志愿者和患者的肝脏进行了扫描。在患者中，将斑点跟踪结果与手动勾画肿瘤的治疗计划 4 维 CT 以及手动在灰度超声图像上进行的估计进行了比较。志愿者中扫描了右肺和前列腺的表面。在志愿者中，在呼吸期间扫描了肝脏和肺表面。为了模拟前列腺运动，在前后方向上摇动超声探头。所有部位的所有运动测量的相关系数均具有显著相关性（所有部位 P <.00001），且无时间延迟。超声斑点跟踪肿瘤运动的运动估计值与手动在灰度超声图像和 4 维 CT 上跟踪的运动估计值相差 2 毫米以内。总肿瘤运动大于 20 毫米。前列腺的角位移在 0.02 弧度（1.1°）以内，与手动测量的位移相当。斑点跟踪可用于监测放射治疗过程中的器官运动。
