[19a-A304-1~11] 2.3 Application, radiation generators, new technology

[19a-A304-1] Image quality characteristics of two-dimensional CdTe X-ray sennsor and discrimination ability of material of human body equivalent phantoms

〇Masao Matsumoto¹, Rena Iwasaki², Yuki Okada² (1.Medicine,Osaka Univ., 2.Osaka Univ.)

Keywords:two-dimensional CdTe X-ray image sensor, image quality characteristics, discrimination ability

[Purpose] In the two-dimensional CdTe X-ray image sensor, the identification accuracy of the material (linear attenuation coefficient μ (E), effectiv e atomic number Z) of the human body equivalent phantom object is obtained a nd image quality characteristics of the two-dimensional CdTe X-ray image sensor are measured[Methods]Two dimensional plane image is acquired in the ener gy region 30 to 75 keV region in each material of the human body equivalent phantoms. Measurement was performed under the condition of acquisition inter val of 3 keV, and comparison was made from the acquired image, the linear at tenuation coefficient for each energy was calculated using the number of inc ident photons and the number of transmitted photons (the number of transmitt ed photons / the number of incident photons). From the obtained linear atten uation coefficient, the effective atomic number of each subject is calculate d from the logarithmic ratio of the linear attenuation coefficients of two d ifferent energy regions, and the discrimination accuracy of the material of each object is discussed. We also measured the digital characteristic curve, MTF, Wiener spectrum, NEQ and DQE which are the image quality characterist ics of the two-dimensional CdTe X-ray image sensor together.[Results] With t ube voltage 100 kV, energy acquisition interval 3 keV, Human body equivalent phantoms measured for linear attenuation coefficient μ (E). As a result of determining the effective atomic number Z of the material of the object.
In addition, the image quality characteristics of the two-dimensional CdTe X-ray image sensor ( digital characteristic curves, MTF, Wiener spectrum) we re measured.[Conclusion] Its identification accuracy of human body equivale nt phantoms was 7.0%. In addition, the image quality characteristics of th e two-dimensional CdTe X-ray image sensor ( characteristic curves, MTF, WS) were measured. We also measure the image quality characteristics of NEQ an d DQE of a two-dimensional CdTe X-ray image sensor.