Low Dose CT Scan
Application value of " one-stop" scanning of coronary and head and neck CTA using low tube voltage
Li Wanjiang, Yu Jianqun, Shuai Tao, Tan Jia, Peng Wanlin, Liu Zixuan, Zhu Yao, Li Zhenlin
Published 2019-01-25
Cite as Chin J Radiol Med Prot, 2019, 39(1): 11-15. DOI: 10.3760/cma.j.issn.0254-5098.2019.01.003
Abstract
ObjectiveTo investigate the value of " one-stop" scanning of coronary and head and neck CTA in patients with normal body mass index (18 kg/m 2 ≤ BMI ≤ 25 kg/m2) using low tube voltage (80 kVp).
MethodsIn a retrospective analysis 80 patients with normal body mass index who had completed " one-stop" scanning of coronary and head and neck CTA were divided into A and B groups according to different scanning method, and 40 consecutive cases were selected in each group. Scanning parameters of group A and group B were tube voltage 80 kV, coronary CTA tube current 550 mA, head and neck CTA tube current 500 mA, and tube voltage 100 kV, coronary CTA tube current 450 mA, head and neck CTA tube current 400 mA separately. Subjective evaluation and objective evaluation were performed on the image quality of the two groups. CT values of coronary artery and head and neck CTA trunk branch vessel, contrast-to-noise ratio (CNR), image noise (SD) and effective dose between the two groups were compared.
ResultsThe image quality of both groups met the diagnostic requirements, and there was no statistically significant difference in subjective scores between two groups (P>0.05). The CT values of coronary arteries, the main branches of the head and neck (the common carotid artery, the internal carotid artery) and SD of head and neck CTA were significantly different between two groups (t=4.737, 6.552, 3.359, 2.165, 2.685, 4.617, P<0.05). There was no statistically significant difference in SD of coronary CTA, CT values and CNR between head and neck vessels (middle cerebral artery) in group A and group B (P>0.05). The effective dose of coronary CTA in group A (1.16±0.20)mSv was reduced by 51.1% than that in group B (2.37±0.77)mSv. The effective dose of head and neck CTA in group A (0.37±0.03)mSv was reduced by 47.9% than that in group B (0.71±0.17)mSv.
ConclusionsThe image quality with subjective evaluation met the diagnostic requirements when using a low-tube voltage for " one-stop" scanning of coronary and head and neck CTA. The CNR values were basically consistent with the conventional scanning method, and the patient effective dose was reduced by about 50%.
Key words:
Coronary vessels; Carotid arteries; Cerebral arteries; Angiography; Effective dose
Contributor Information
Li Wanjiang
Department of Radiology, West China Hospital, Sichuan University, Chengdu 610041, China
Yu Jianqun
Shuai Tao
Tan Jia
Peng Wanlin
Liu Zixuan
Zhu Yao
Li Zhenlin
