Clinical study of pulmonary embolism CT imaging using the third generation dual-source CT with low tube voltage and low contrast dosage
10.3760/cma.j.issn.0254-5098.2020.09.011
- VernacularTitle:基于第3代双源CT双低检查技术在肺栓塞成像的临床应用研究
- Author:
Qing FU
1
;
Ming YANG
;
Ziqiao LEI
;
Jianming YU
Author Information
1. 华中科技大学同济医学院附属协和医院放射科 分子影像湖北省重点实验室，武汉 430022
- From:
Chinese Journal of Radiological Medicine and Protection
2020;40(9):712-716
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To investigate the clinical value of third-generation dual-source CT with high pitch, 70 kV combined with 16 ml contrast agent in low radiation dose imaging of pulmonary embolism (PE).Methods:Eighty-three patients with suspected PE underwent CT pulmonary angiography were randomly divided into two groups: group A with 36 cases, 100 kV, 1.0 pitch, and 60 ml contrast agent; group B with 47 cases, 70 kV, 2.2 pitch, and 16 ml contrast agent. The volume CT dose index and dose length product of the two groups were recorded to calculate the effective dose E, and the CT values of enhanced pulmonary arteries, background noise, and muscles values were recorded to calculate signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR). The overall image quality and the beam-hardening artifact of superior vena cava were subjectively evaluated on a 3-point scale. Results:There were no significant differences in gender, age, height, weight, BMI, proportion of PE, and CT values of enhanced pulmonary arteries at all levels ( P>0.05). The value E of group B was (0.76±0.13) mSv, significantly lower than that in group A [(1.91±0.54) mSv, Z=-5.23, P<0.001]. Although background noise of group B was significantly higher than that of group A ( Z=-4.99, P <0.001), SNR and CNR values of group B were significantly lower than those of group A ( Z=-4.56, -4.48, P<0.001), there was no statistically significant difference in the overall image quality scores between the two groups ( P>0.05). The beam-hardening artifact caused by superior vena cava in group B was significantly lower than that in group A ( Z=-5.15, P <0.001). Conclusions:The third generation dual-source CT with high pitch, 70 kV combined with 16 ml contrast agent can significantly reduce the interference of contrast agent beam-hardening artifact on the right and right superior pulmonary arteries to ensure the diagnostic image quality of PE, and effectively reduce radiation dose by 60% and total volume of contrast agent by 73%.
