Dual- and multi-energy CT: approach to functional imaging.
Dual- and multi-energy CT: approach to functional imaging.
复制标题
双能和多能 CT：功能成像方法。
DOI：
10.1007/s13244-010-0057-0
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发表时间：
2011-04
影响因子：
4.7
通讯作者：
Stolzmann, Paul
中科院分区：
文献类型：
--
作者：
Fornaro, Juergen;Leschka, Sebastian;Hibbeln, Dennis;Butler, Anthony;Anderson, Nigel;Pache, Gregor;Scheffel, Hans;Wildermuth, Simon;Alkadhi, Hatem;Stolzmann, Paul
x射线光子通过吸收体后的能谱包含有关其元素组成的信息。因此，如果吸收特性可以测量或区分，组织表征就变得可行。双能CT使用两个x射线光谱，通过分析材料依赖的光电效应和康普顿效应来实现材料的区分。因此，可以使用三种物质分解算法来确定元素浓度。与临床应用的双能CT相比，最近开发的能量敏感光子计数探测器在多个能级和窄能带内对材料特异性衰减曲线进行采样；后者允许检测元素特异性，k边的光电截面不连续。因此，多能CT成像能够同时识别多种材料，准确性更高。这些关于物质分布的具体数据提供了超越形态CT的信息，并接近功能成像。本文综述了双能和多能CT成像的原理、硬件入路及临床应用。
The energy spectrum of X-ray photons after passage through an absorber contains information about its elemental composition. Thus, tissue characterisation becomes feasible provided that absorption characteristics can be measured or differentiated. Dual-energy CT uses two X-ray spectra enabling material differentiation by analysing material-dependent photo-electric and Compton effects. Elemental concentrations can thereby be determined using three-material decomposition algorithms. In comparison to dual-energy CT used in clinical practice, recently developed energy-sensitive photon-counting detectors sample the material-specific attenuation curves at multiple energy levels and within narrow energy bands; the latter allows the detection of element-specific, k-edge discontinuities of the photo-electric cross section. Multi-energy CT imaging therefore is able to concurrently identify multiple materials with increased accuracy. These specific data on material distribution provide information beyond morphological CT, and approach functional imaging. This article reviews the principles of dual- and multi-energy CT imaging, hardware approaches and clinical applications.