Evaluation of radiation dose in pediatric head CT examination: a phantom study

International Nuclear Science, Technology and Engineering Conference 2017

原子能学

Nik Din, Nik Norhasrina^1 ; Zainon, Rafidah^2 ; Abdul Rahman, Ahmad Taufek^1,3

Department of Physics and Material Studies, Faculty of Applied Sciences, Universiti Teknologi MARA, Selangor Shah Alam

40450, Malaysia^1

Oncological and Radiological Sciences Cluster, Advanced Medical and Dental Institute, Universiti Sains Malaysia, Bertam, Kepala Batas, Pulau Pinang

13200, Malaysia^2

Institute of Science, Universiti Teknologi MARA, Selangor Shah Alam

40450, Malaysia^3

关键词: Automatic exposure controls;    Contrast to noise ratio;    Dual-energy CT;    Image noise;    Phantom studies;    Slice thickness;    Tube currents;    Tube voltages;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/298/1/012046/pdf
DOI  :  10.1088/1757-899X/298/1/012046

来源: IOP

【 摘 要 】

The aim of this study was to evaluate the radiation dose in pediatric head Computed Tomography examination. It was reported that decreasing tube voltage in CT examination can reduce the dose to patients significantly. A head phantom was scanned with dual-energy CT at 80 kV and 120 kV. The tube current was set using automatic exposure control mode and manual setting. The pitch was adjusted to 1.4, 1.45 and 1.5 while the slice thickness was set at 5 mm. The dose was measured based on CT Dose Index (CTDI). Results from this study have shown that the image noise increases substantially with low tube voltage. The average dose was 2.60 mGy at CT imaging parameters of 80 kV and 10 - 30 mAs. The dose increases up to 17.19 mGy when the CT tube voltage increases to 120 kV. With the reduction of tube voltage from 120 kV to 80 kV, the radiation dose can be reduced by 12.1% to 15.1% without degradation of contrast-to-noise ratio.