Electron Density and Effective Atomic Number Measurement by Using a Newly Developing Photon Counting CT System

Abstract:

We developed the photon counting CT system by using a conventional laboratory X-ray source and a CdTe line sensor. Attenuation coefficients were obtained from the measured CT image data. Our suggested method for deriving the electron density and effective atomic number from the measured attenuation coefficients was tested experimentally. The accuracy of the electron densities and effective atomic numbers are about <5 % (the averages of absolute values are 2.6 % and 3.1 %, respectively) for material of 6< Z and Zeff <13. Our suggested simple method, in which we do not need the exact source X-ray spectrum and detector response function, achieves comparable accuracy to the previous reports.

• Periodical: Advanced Engineering Forum (Volume 38)
• Pages: 93-99
• DOI: https://doi.org/10.4028/www.scientific.net/AEF.38.93
• Online since: November 2020
• Authors: Hiroshi Sakurai*, Kazushi Hoshi, Yosuke Harasawa, Daiki Ono, Kun Zhang, Akie Nagao, Yumiko Ohno, Naoki Sunaguchi, Kosuke Suzuki, Masami Torikoshi
• Keywords: Effective Atomic Number, Electron Density, Photon Counting CT, Radiotherapy

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