Abstract:Objective To investigate the CT weighted dose index measurement and its influence on the
image quality of PET/CT under different tube voltage. Methods In the tube respectively voltage of 140,
120, 100, 80 kV and other conditions, we used PET/CT system to scan the simulate performance of the
body and the CT dose phantom body of Catphan?500 CT. The related characters of the CT image were
measured. Meanwhile, the CT dose index of weighted (CTDIw) under different tube voltage and the CT
dose index of volume (CTDIvol) under given pitches were measured and calculated. Results The high
contrast resolution of the CT images were not affected by the tube voltage. However, with the increase
of the tube voltage, the low contrast resolution of the CT images, CTDIvol, the uniform and noise
performance of the CT images were increased. When in low contrast resolution of 0.30%, 0.50% and
1.00%, the contrast of the images increased with the increasing of the tube voltage. The CT image uniformity
also increased with the increasing of tube voltage. The changes was in a small range when the tube voltage was
in 120~140 kV and the changes was in a bigger range in 80~100 kV. The CTDIvol increased linearly
with the increasing of the tube voltage, while improving performance was nonlinear rules. Conclusion
With the reduction of tube voltage, the CT dose of PET/CT is also reduced, and the appropriate dose of
CT dose not affect the quality of CT image when the CT dose is more than a certain value.
钟承双,徐谢生. PET/CT不同管电压下的CT加权剂量指数测量及其对图像质量的影响[J]. 中国医疗设备, 2017, 32(5): 105-107.
ZHONG Cheng-shuang,
XU Xie-sheng. CT Weighted Dose Index Measurement Under Different Tube Voltage of
PET/CT and Its Influence on Image Quality. China Medical Devices, 2017, 32(5): 105-107.