Department of Medical Physics and Bioengineering, UCL, Gower Street, London WC1E 6BT, United Kingdom.
Med Phys. 2013 Sep;40(9):090701. doi: 10.1118/1.4817480.
To provide an x-ray phase contrast imaging (XPCI) method working with conventional sources that could be readily translated into clinical practice. XPCI shows potential in synchrotron studies but attempts at translating it for use with conventional sources are subject to limitations in terms of field of view, stability, exposure time, and possibly most importantly, delivered dose.
Following the adaptation of our "edge-illumination" XPCI technique for use with conventional x-ray sources through the use of x-ray masks, the authors have further modified the design of such masks to allow further reducing the dose delivered to the sample without affecting the phase sensitivity of the method.
The authors have built a prototype based on the new mask design and used it to image ex vivo breast tissue samples containing malignant lesions. The authors compared images acquired with this prototype to those obtained with a conventional system. The authors demonstrate and quantify image improvements, especially in terms of microcalcification detection. On calcifications detected also by the conventional system, the authors measure contrast increases from five to nine fold; calcifications and other features were also detected which are completely invisible in the conventional image. Dose measurements confirmed that the above enhancements were achieved while delivering doses compatible with clinical practice.
The authors obtained phase-related image enhancements in mammography by means of a system built with components available off-the-shelf that operates under exposure time and dose conditions compatible with clinical practice. This opens the way to a straightforward translation of phase enhanced imaging methods into clinical practice.
提供一种可与常规光源配合使用的 X 射线相衬成像（XPCI）方法，以便于转化为临床实践。XPCI 在同步加速器研究中具有潜力，但尝试将其转化为常规光源使用受到视场、稳定性、曝光时间以及最重要的是，所传递剂量的限制。
通过使用 X 射线掩模将我们的“边缘照明”XPCI 技术改编为可与常规 X 射线源配合使用，作者进一步修改了掩模的设计，以在不影响方法相敏性的情况下进一步降低样品所接受的剂量。
作者基于新掩模设计构建了一个原型，并将其用于对包含恶性病变的离体乳房组织样本进行成像。作者将该原型获得的图像与传统系统获得的图像进行了比较。作者证明并量化了图像改进，特别是在微钙化检测方面。对于传统系统也能检测到的钙化，作者测量到对比度提高了五到九倍；还检测到了在传统图像中完全不可见的钙化和其他特征。剂量测量证实，在传递与临床实践兼容的剂量的同时，实现了上述增强。
作者通过使用现成组件构建的系统，在乳房 X 光摄影中获得了与相位相关的图像增强，该系统在与临床实践兼容的曝光时间和剂量条件下运行。这为将相位增强成像方法直接转化为临床实践开辟了道路。
