IEEE Trans Med Imaging. 2024 Jan;43(1):28-38. doi: 10.1109/TMI.2023.3288358. Epub 2024 Jan 2.
Grating-based X-ray phase-contrast and in particular dark-field radiography are promising new imaging modalities for medical applications. Currently, the potential advantage of dark-field imaging in early-stage diagnosis of pulmonary diseases in humans is being investigated. These studies make use of a comparatively large scanning interferometer at short acquisition times, which comes at the expense of a significantly reduced mechanical stability as compared to tabletop laboratory setups. Vibrations create random fluctuations of the grating alignment, causing artifacts in the resulting images. Here, we describe a novel maximum likelihood method for estimating this motion, thereby preventing these artifacts. It is tailored to scanning setups and does not require any sample-free areas. Unlike any previously described method, it accounts for motion in between as well as during exposures.
基于光栅的 X 射线相衬成像，尤其是暗场射线照相术，是一种很有前途的医学应用新成像方式。目前，正在研究暗场成像在人类肺部疾病早期诊断中的潜在优势。这些研究利用了在短采集时间内具有较大扫描干涉仪，这与台式实验室设备相比，机械稳定性显著降低。振动会导致光栅对准发生随机波动，从而在生成的图像中产生伪影。在这里，我们描述了一种用于估计这种运动的新的最大似然方法，从而可以防止这些伪影。它是专门为扫描设置而设计的，不需要任何无样本区域。与以前描述的任何方法不同，它既考虑了曝光期间的运动，也考虑了曝光之间的运动。
