A new scheme for real-time high-contrast imaging in lung cancer radiotherapy: a proof-of-concept study.
A new scheme for real-time high-contrast imaging in lung cancer radiotherapy: a proof-of-concept study.
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DOI：
10.1088/0031-9155/61/6/2372
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发表时间：
2016-03-21
影响因子：
3.5
通讯作者：
Jia X
中科院分区：
文献类型：
--
作者：
Yan H;Tian Z;Shao Y;Jiang SB;Jia X
解剖结构的真实的可视化对于肺癌放疗中的运动管理至关重要。为了实现实时，高对比度的治疗成像，我们提出了一种新的方案的基础上测量的康普顿散射光子。在我们的方法中，沿着上下（SI）方向的狭缝X射线束指向患者（在2D平面处与肺区域相交），包含大部分肿瘤运动轨迹。X射线光子主要由于康普顿相互作用而从该平面散射。将具有针孔或板条准直器的成像器放置在平面的一侧以捕获散射的光子。在对入射通量不均匀性、X射线衰减、散射角变化和出射束几何形状进行校正之后，所得到的图像表示康普顿散射的线性衰减系数。这允许在该平面上可视化解剖结构。为了验证原理，我们对体模和患者进行了蒙特卡罗（MC）模拟研究。在体模病例中，可以清楚地看到小的肿瘤样结构。对于kV透视、锥形束CT（CBCT）和散射图像，使用肿瘤/肺作为前景/背景计算的对比度分辨率分别为0.037、0.70和0.54。在患者病例中，在散射图像中可以清楚地观察到肿瘤运动。通过狭缝束直接暴露的体素的成像剂量是单个CBCT投影下的成像剂量的约0.4倍。这些研究证明了所提出的成像方案在具有高图像对比度的2D平面上捕获患者的瞬时解剖结构的潜力。肿瘤运动的清晰可视化可以促进无标记肿瘤跟踪。
Visualization of anatomy in real time is of critical importance for motion management in lung cancer radiotherapy. To achieve real-time, and high-contrast in-treatment imaging, we propose a novel scheme based on the measurement of Compton scatter photons. In our method, a slit x-ray beam along the superior-inferior (SI) direction is directed to the patient, (intersecting the lung region at a 2D plane) containing most of the tumor motion trajectory. X-ray photons are scattered off this plane primarily due to the Compton interaction. An imager with a pinhole or a slat collimator is placed at one side of the plane to capture the scattered photons. The resulting image, after correcting for incoming fluence inhomogeneity, x-ray attenuation, scatter angle variation, and outgoing beam geometry, represents the linear attenuation coefficient of Compton scattering. This allows the visualization of the anatomy on this plane. We performed Monte Carlo (MC) simulation studies both on a phantom and a patient for proof-of-principle purposes. In the phantom case, small tumor-like structure could be clearly visualized. The contrast-resolution calculated using tumor/lung as foreground/background for kV fluoroscopy, cone-beam CT (CBCT), and scattering image were 0.037, 0.70, and 0.54, respectively. In the patient case, tumor motion could be clearly observed in the scatter images. Imaging dose to the voxels directly exposed by the slit beam was ~0.4 times of that under a single CBCT projection. These studies demonstrated the potential of the proposed imaging scheme to capture the instantaneous anatomy of a patient on a 2D plane with a high image contrast. Clear visualization of the tumor motion may facilitate marker-less tumor tracking.
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影响因子：
3.5
作者：
Dietrich, Lars;Jetter, Siri;Oelfke, Uwe
通讯作者：
Oelfke, Uwe
影响因子：
2.6
作者：
Ahn, S;Yi, B;Choi, E
通讯作者：
Choi, E
影响因子：
3.5
作者：
Cheung, Joey;Kudchadker, Rajat J.;Newhauser, Wayne D.
通讯作者：
Newhauser, Wayne D.
DOI：
10.1016/j.ijrobp.2004.07.681
发表时间：
2004-11-15
影响因子：
7
作者：
Hoisak, JDP;Sixel, KE;Pignol, JP
通讯作者：
Pignol, JP
影响因子：
--
作者：
Klein, O.;Nishina, Y.
通讯作者：
Nishina, Y.