Study on the Influencing Factors and Long-term Stability of the CT Number of Siemens Large Aperture CT Simulator
HU Jin-you1,2,ZOU Lian1,XIE Zhao1,LUO Ke-lin1,YIN Yun-peng1,ZHANG Wei-sha1
1. Cancer Center, Sichuan Academy of Medical Sciences Sichuan Provincial People‘s Hospital, Chengdu,Sichuan 610072, China
2. Key Laboratory of Radiation Physics and Technology of the Ministry of Education, Institute of Nuclear Science and Technology, Sichuan University, Chengdu, Sichuan 610064, China
摘要通过改变西门子CT模拟机电流时间乘积、电压,重建卷积核,研究扫描参数对CIRS-062M模体CT值的影响。回顾分析CIRS-062M模体年质控数据、CTP504模体月质控数据, 研究CT值的长期稳定性。结果表明电流时间乘积对CT值几乎无影响,最大变化4.6HU;电压对CT值影响较大,最大变化达585.3HU;除Head H31s及Child Head H21s两种卷积核外,其余卷积核对CT值影响轻微;近几年内2种模体的CT值均保持较好的一致性,变化最大为CIRS-062M致密骨插件,最大变化63.3HU,平均变化(-8.68±17.82)HU。
Abstract：The influence of scanning parameters on the CT number of CIRS-062M phantom was studied by changing the current time product, voltage and reconstruction convolution kernel of Siemens CT simulator.The annual quality assurance data of CIRS-062M phantom and the monthly quality assurance data of CTP504 phantom were retrospectively analyzed to study the long-term stability of CT number.The results show that the current time product has almost no effect on the CT number, and the maximum change is 4.6HU.The voltage has great influence on the CT number, with the maximum change of 585.3HU. Except for the Head H31s and Child Head H21s convolution kernels, the other convolution kernels have slight influence on the CT number.The CT number of the two phantoms have maintained good consistency in recent years, the maximum change is dense bone in CIRS-062M phantom, with a maximum change of 63.3HU and an average change of (-8.68±17.82)HU.
胡金有,邹炼,谢朝,骆科林,殷云鹏,张薇莎. 西门子大孔径CT模拟定位机CT值影响因素及其长期稳定性研究[J]. 计量学报, 2023, 44(5): 783-789.
HU Jin-you,ZOU Lian,XIE Zhao,LUO Ke-lin,YIN Yun-peng,ZHANG Wei-sha. Study on the Influencing Factors and Long-term Stability of the CT Number of Siemens Large Aperture CT Simulator. Acta Metrologica Sinica, 2023, 44(5): 783-789.
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2023, Vol. 44 
