Respiratory gating in positron emission tomography:: A quantitative comparison of different gating schemes
Respiratory gating in positron emission tomography:: A quantitative comparison of different gating schemes
复制标题
DOI：
10.1118/1.2748104
复制
发表时间：
2007-07-01
期刊：
影响因子：
3.8
通讯作者：
Schaefers, Klaus P.
中科院分区：
文献类型：
--
作者：
Dawood, Mohammad;Buether, Florian;Schaefers, Klaus P.
呼吸门控用于减少呼吸运动的影响在广泛的应用，从放射治疗到诊断成像。不同的呼吸门控方法是可行的。本研究开发了七种门控方法，并对正电子发射断层扫描（PET）的表模数据进行了测试。对7例患者的研究结果进行了运动和噪声方面的定量比较。(1)等量和(2)可变时间门控方法仅使用呼吸周期的时间信息来定义呼吸门。(3)基于等幅和可变幅值的门控方法利用呼吸信号的幅值。(5)基于周期的幅度门控是基于时间和基于幅度的技术的结合。对方法(3)和(4)进行基线校正，产生两种新方法：基线校正(6)相等门控和(7)可变振幅门控。7例患者的Listmode PET数据与呼吸信号一起获得。采用7种门控方法对图像进行重构。使用两个参数来量化结果：运动被测量为由于呼吸引起的心脏位移，噪声被定义为背景区域像素强度的标准偏差。基于振幅的方法(3)和(4)优于基于时间的方法(1)和(2)。所有受试者在捕捉动作方面的改善都超过30%（最高达130%）。与等时间(1)和等幅度(3)方法相比，变时间(2)和变幅度(4)方法在所有呼吸门之间的噪声分布更为均匀。基线校正并没有改善结果。在七种不同的呼吸门控方法中，可变振幅法(4)在所有呼吸阶段保持恒定噪声水平的同时，最好地捕捉呼吸运动。(C) 2007年美国医学物理学家协会。
Respiratory gating is used for reducing the effects of breathing motion in a wide range of applications from radiotherapy treatment to diagnostical imaging. Different methods are feasible for respiratory gating. In this study seven gating methods were developed and tested on positron emission tomography (PET) listmode data. The results of seven patient studies were compared quantitatively with respect to motion and noise. (1) Equal and (2) variable time-based gating methods use only the time information of the breathing cycle to define respiratory gates. (3) Equal and (4) variable amplitude-based gating approaches utilize the amplitude of the respiratory signal. (5) Cycle-based amplitude gating is a combination of time and amplitude-based techniques. A baseline correction was applied to methods (3) and (4) resulting in two new approaches: Baseline corrected (6) equal and (7) variable amplitude-based gating. Listmode PET data from seven patients were acquired together with a respiratory signal. Images were reconstructed applying the seven gating methods. Two parameters were used to quantify the results: Motion was measured as the displacement of the heart due to respiration and noise was defined as the standard deviation of pixel intensities in a background region. The amplitude-based approaches (3) and (4) were superior to the time-based methods (1) and (2). The improvement in capturing the motion was more than 30% (up to 130%) in all subjects. The variable time (2) and amplitude (4) methods had a more uniform noise distribution among all respiratory gates compared to equal time (1) and amplitude (3) methods. Baseline correction did not improve the results. Out of seven different respiratory gating approaches, the variable amplitude method (4) captures the respiratory motion best while keeping a constant noise level among all respiratory phases. (C) 2007 American Association of Physicists in Medicine.