Department of Radiation Oncology, Fujian Medical University Union Hospital, Fuzhou, China.
Fujian Medical University Union Clinical Medicine College, Fujian Medical University, Fuzhou, China.
J Appl Clin Med Phys. 2024 Jul;25(7):e14341. doi: 10.1002/acm2.14341. Epub 2024 Apr 15.
The Xsight lung tracking system (XLTS) utilizes an advanced image processing algorithm to precisely identify the position of a tumor and determine its location in orthogonal x-ray images, instead of finding fiducials, thereby minimizing the risk of fiducial insertion-related side effects. To assess and gauge the effectiveness of CyberKnife Synchrony in treating liver tumors located in close proximity to or within the diaphragm, we employed the Xsight diaphragm tracking system (XDTS), which was based on the XLTS.
We looked back at the treatment logs of 11 patients (8/11 [XDTS], 3/11 [Fiducial-based Target Tracking System-FTTS]) who had liver tumors in close proximity to or within the diaphragm. And the results are compared with the patients who undergo the treatment of FTTS. The breathing data information was calculated as a rolling average to reduce the effect of irregular breathing. We tested the tracking accuracy with a dynamic phantom (18023-A) on the basis of patient-specific respiratory curve.
The average values for the XDTS and FTTS correlation errors were 1.38 ± 0.65 versus 1.50 ± 0.26 mm (superior-inferior), 1.28 ± 0.48 versus 0.40 ± 0.09 mm (left-right), and 0.96 ± 0.32 versus 0.47 ± 0.10 mm(anterior-posterior), respectively. The prediction errors for two methods of 0.65 ± 0.16 versus 5.48 ± 3.33 mm in the S-I direction, 0.34 ± 0.10 versus 1.41 ± 0.76 mm in the A-P direction, and 0.22 ± 0.072 versus 1.22 ± 0.48 mm in the L-R direction. The coverage rate of FTTS slightly less than that of XDTS, such as 96.53 ± 8.19% (FTTS) versus 98.03 ± 1.54 (XDTS). The prediction error, the motion amplitude, and the variation of the respiratory center phase were strongly related to each other. Especially, the higher the amplitude and the variation, the higher the prediction error.
The diaphragm has the potential to serve as an alternative to gold fiducial markers for detecting liver tumors in close proximity or within it. We also found that we needed to reduce the motion amplitude and train the respiration of the patients during liver radiotherapy, as well as control and evaluate their breathing.
Xsight 肺部跟踪系统（XLTS）利用先进的图像处理算法精确识别肿瘤的位置，并确定其在正交 X 射线图像中的位置，而不是寻找基准标记，从而最大限度地降低基准标记插入相关副作用的风险。为了评估和衡量 CyberKnife Synchrony 治疗靠近或位于膈肌内的肝脏肿瘤的有效性，我们使用了基于 XLTS 的 Xsight 膈肌跟踪系统（XDTS）。
我们回顾了 11 名患者（8/11 [XDTS]，3/11 [基于基准标记的目标跟踪系统-FTTS]）的治疗记录，这些患者的肝脏肿瘤靠近或位于膈肌内。并将结果与接受 FTTS 治疗的患者进行比较。呼吸数据信息被计算为滚动平均值，以减少不规则呼吸的影响。我们根据患者特定的呼吸曲线，在动态体模（18023-A）上测试了跟踪准确性。
XDTS 和 FTTS 相关误差的平均值分别为 1.38±0.65 毫米（上下）、1.28±0.48 毫米（左右）和 0.96±0.32 毫米（前后）；0.65±0.16 毫米和 5.48±3.33 毫米（S-I 方向）、0.34±0.10 毫米和 1.41±0.76 毫米（A-P 方向）、0.22±0.072 毫米和 1.22±0.48 毫米（L-R 方向）。FTTS 的预测误差稍小于 XDTS，如 96.53±8.19%（FTTS）与 98.03±1.54%（XDTS）。预测误差、运动幅度和呼吸中心相位的变化彼此强烈相关。特别是，幅度和变化越大，预测误差越高。
膈肌有可能替代金基准标记来检测靠近或位于其中的肝脏肿瘤。我们还发现，在进行肝脏放疗时，我们需要降低运动幅度并训练患者的呼吸，同时控制和评估他们的呼吸。
