Section Biomedical Imaging, Delft University of Technology, Delft, Netherlands.
Phys Med Biol. 2017 Dec 19;63(1):015018. doi: 10.1088/1361-6560/aa9265.
Imaging of Tc-labelled tracers is gaining popularity for detecting breast tumours. Recently, we proposed a novel design for molecular breast tomosynthesis (MBT) based on two sliding focusing multi-pinhole collimators that scan a modestly compressed breast. Simulation studies indicate that MBT has the potential to improve the tumour-to-background contrast-to-noise ratio significantly over state-of-the-art planar molecular breast imaging. The aim of the present paper is to optimize the collimator-detector geometry of MBT. Using analytical models, we first optimized sensitivity at different fixed system resolutions (ranging from 5 to 12 mm) by tuning the pinhole diameters and the distance between breast and detector for a whole series of automatically generated multi-pinhole designs. We evaluated both MBT with a conventional continuous crystal detector with 3.2 mm intrinsic resolution and with a pixelated detector with 1.6 mm pixels. Subsequently, full system simulations of a breast phantom containing several lesions were performed for the optimized geometry at each system resolution for both types of detector. From these simulations, we found that tumour-to-background contrast-to-noise ratio was highest for systems in the 7 mm-10 mm system resolution range over which it hardly varied. No significant differences between the two detector types were found.
Tc 标记示踪剂的成像技术在检测乳腺癌方面越来越受欢迎。最近，我们提出了一种基于两个滑动聚焦多针孔准直器的新型分子乳腺断层合成（MBT）设计，该设计可以扫描适度压缩的乳房。模拟研究表明，与最先进的平面分子乳腺成像相比，MBT 有可能显著提高肿瘤与背景的对比度噪声比。本研究的目的是优化 MBT 的准直器-探测器几何形状。我们首先使用解析模型，通过调整针孔直径和乳房与探测器之间的距离，针对一系列自动生成的多针孔设计，在不同的固定系统分辨率（5 至 12 毫米）下优化灵敏度。我们评估了具有 3.2 毫米固有分辨率的传统连续晶体探测器和具有 1.6 毫米像素的像素化探测器的 MBT。随后，针对两种探测器类型，在每个系统分辨率下，对包含多个病变的乳房体模进行了完整系统的模拟。从这些模拟中，我们发现对于 7 毫米至 10 毫米系统分辨率范围内的系统，肿瘤与背景的对比度噪声比最高，且几乎没有变化。两种探测器类型之间没有发现显著差异。
