Chair of Biomedical Physics, Department of Physics, School of Natural Sciences, Technical University of Munich, 85748, Garching, Germany.
Munich Institute of Biomedical Engineering, Technical University of Munich, 85748, Garching, Germany.
Sci Rep. 2021 Dec 6;11(1):23504. doi: 10.1038/s41598-021-02960-2.
X-ray dark-field imaging is a widely researched imaging technique, with many studies on samples of very different dimensions and at very different resolutions. However, retrieval of three-dimensional (3D) information for human thorax sized objects has not yet been demonstrated. We present a method, similar to classic tomography and tomosynthesis, to obtain 3D information in X-ray dark-field imaging. Here, the sample is moved through the divergent beam of a Talbot-Lau interferometer. Projections of features at different distances from the source seemingly move with different velocities over the detector, due to the cone beam geometry. The reconstruction of different focal planes exploits this effect. We imaged a chest phantom and were able to locate different features in the sample (e.g. the ribs, and two sample vials filled with water and air and placed in the phantom) to corresponding focal planes. Furthermore, we found that image quality and detectability of features is sufficient for image reconstruction with a dose of 68 μSv at an effective pixel size of [Formula: see text]. Therefore, we successfully demonstrated that the presented method is able to retrieve 3D information in X-ray dark-field imaging.
X 射线暗场成像是一种广泛研究的成像技术，有许多关于非常不同尺寸和非常不同分辨率的样本的研究。然而，对于人类胸部大小的物体，还没有展示出三维（3D）信息的检索。我们提出了一种类似于经典断层扫描和断层合成的方法，以在 X 射线暗场成像中获得 3D 信息。在这里，样品在泰伯-劳（Talbot-Lau）干涉仪的发散光束中移动。由于锥束几何形状，源的不同距离处的特征的投影在探测器上似乎以不同的速度移动。不同焦平面的重建利用了这一效应。我们对一个胸部模型进行了成像，并能够将样品中的不同特征（例如肋骨，以及两个装在模型中的装有水和空气的小瓶）定位到相应的焦平面。此外，我们发现，对于有效像素尺寸为 [Formula: see text] 的图像重建，特征的图像质量和可检测性足以满足要求，剂量为 68μSv。因此，我们成功地证明了所提出的方法能够在 X 射线暗场成像中检索 3D 信息。
