摘要
近年来,基于光子计数探测器成像的能谱CT(Computed Tomography)是辐射成像领域内的一个研究热点。通过设置不同的能量阈值,光子计数探测器可将不同能量的入射光子分能窗计数,使采集信号携带了能量信息。通过对多个能窗的CT数据进行解析,能谱CT不仅可以进行物质识别,还可以具有高信噪比、高分辨率等特点,并降低被测物体所受辐射剂量。本文从光子计数探测器、能谱CT重建算法和能谱CT系统三个方面对能谱CT的关键技术和研究现状进行阐述:1光子计数探测器的工作原理及标定方法,并讨论影响标定的因素;2能谱CT的多能分解方法和重建算法;3能谱CT系统平台及应用;最后总结了各个方向的研究内容及热点。
Recently, spectral Computed Tomography （SCT） based on photon counting detectors （PCDs）has become a hot topic in the field of radiation imaging. By setting different energy thresholds in PCD, in- cident photons are counted into different energy bins, which provides us with signals carrying energy infor- mation. By processing CT data from multiple energy bins, material composition of scanned objects can be estimated from spectral CT. This PCD -based SCT images can be of high contrast- to- noise ratio （CNR） and high spatial resolution. Dose reduction is reviews the key technologies and research progress in physics and calibration methods of PCD with related another potential benefit of spectral CT. This paper PCD - based SCT from three major aspects ： （1）basic key issues discussed, （2）reconstruction methods for SCT including multi - energy decomposition and regularization/prior applicable in iterative reconstruction, and （3）systems and application of SCT. A summary of important topics and research interests are included in the end.
作者
冯初晴
郭潇月
郑奡
邢宇翔
FENGC huqing GUO Xiaoyue ZHEN GAo XING Yuxiang(Department of Engineering Physics, Tsinghua University, Beijing 100084, China Key Laboratory of Particle ＆ Radiation Imaging （Tsinghua University） , Ministry of Education, Beijiug 100084, China)
出处
《中国体视学与图像分析》
2016年第4期353-366,共14页
Chinese Journal of Stereology and Image Analysis
基金
国家重点研发计划重大科学仪器设备开发重大专项(No.2016YFF0101300)
国家自然科学基金(No.11275104
No.11435007)
关键词
能谱CT
光子计数探测器
标定
系统
图像重建算法
spectral CT
photon counting detector
calibration
system
image reconstruction algorithms
