MID-VENTILATION CONCEPT FOR MOBILE PULMONARY TUMORS: INTERNAL TUMOR TRAJECTORY VERSUS SELECTIVE RECONSTRUCTION OF FOUR-DIMENSIONAL COMPUTED TOMOGRAPHY FRAMES BASED ON EXTERNAL BREATHING MOTION
MID-VENTILATION CONCEPT FOR MOBILE PULMONARY TUMORS: INTERNAL TUMOR TRAJECTORY VERSUS SELECTIVE RECONSTRUCTION OF FOUR-DIMENSIONAL COMPUTED TOMOGRAPHY FRAMES BASED ON EXTERNAL BREATHING MOTION
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DOI：
10.1016/j.ijrobp.2008.12.062
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发表时间：
2009-06-01
影响因子：
7
通讯作者：
Flentje, Michael
中科院分区：
文献类型：
--
作者：
Guckenberger, Matthias;Wilbert, Juergen;Flentje, Michael
目的：为了评估的准确性直接重建的中间通气和峰值相位四维（4-D）计算机断层扫描（CT）帧的基础上外部breathingsignal.Methods和材料：11例患者15肺目标，呼吸相关的CT研究（4D CT）被收购治疗计划。在对原始投影数据进行回顾性基于时间的分类并重建在呼吸周期内均匀分布的8个CT帧后，基于内部肿瘤轨迹对平均肿瘤位置（P（平均值））、通气帧和呼吸运动进行评价。分析的外部呼吸信号（压力传感器周围的腹部）与基于振幅的排序的投影进行直接重建的中间通气帧和帧在高峰期的呼吸cycle.Results：的基础上的8个4D CT帧等间距的时间，肿瘤运动是最大的在头尾方向，平均12 +/- 7尼姆。在峰期重建的两帧之间的肿瘤运动在头尾和前后方向上没有差异，但在左右方向上平均系统性地小1 mm。基于内部肿瘤轨迹，Pmean和中间通气帧中肿瘤位置之间的三维距离为1.2 +/- 1 mm。在外部呼吸信号的平均振幅位置重建中间通气帧，导致肿瘤位置距离P（平均值）2.0 +/- 1.1 mm。呼吸引起的运动伪影中通气帧引起的肿瘤体积和形状可以忽略不计的变化。结论：直接重建的中通气帧和帧在峰值相位的基础上外部呼吸信号是可靠的。这使得仅三个4D CT帧的重建足以在临床实践中应用中间通气技术。(C)2009 Elsevier Inc.
Purpose: To evaluate the accuracy of direct reconstruction of mid-ventilation and peak-phase four-dimensional (4-D)computed tomography (CT) frames based on the external breathing signal.Methods and Materials: For 11 patients with 15 pulmonary targets, a respiration-correlated CT study (4D CT) was acquired for treatment planning. After retrospective time-based sorting of raw projection data and reconstruction of eight CT frames equally distributed over the breathing cycle, mean tumor position (P(mean)) mid-ventilation frame, and breathing motion were evaluated based on the internal tumor trajectory. Analysis of the external breathing signal (pressure sensor around abdomen) with amplitude-based sorting of projections was performed for direct reconstruction of the mid-ventilation frame and frames at peak phases of the breathing cycle.Results: On the basis of the eight 4D CT frames equally spaced in time, tumor motion was largest in the craniocaudal direction, with 12 +/- 7 nim on average. Tumor motion between the two frames reconstructed at peak phases was not different in the craniocaudal and anterior-posterior directions but was systematically smaller in the left-right direction by 1 mm on average. The 3-dimensional distance between Pmean and the tumor position in the mid-ventilation frame based on the internal tumor trajectory was 1.2 +/- 1 mm. Reconstruction of the mid-ventilation frame at the mean amplitude position of the external breathing signal resulted in tumor positions 2.0 +/- 1.1 mm distant from P(mean). Breathing-induced motion artifacts in mid-ventilation frames caused negligible changes in tumor volume and shape.Conclusions: Direct reconstruction of the mid-ventilation frame and frames at peak phases based on the external breathing signal was reliable. This makes the reconstruction of only three 4D CT frames sufficient for application of the mid-ventilation technique in clinical practice. (C) 2009 Elsevier Inc.