European Radiology

, Volume 28, Issue 11, pp 4654–4661 | Cite as

Triple-rule-out CT angiography using two axial scans with 16 cm wide-detector for radiation dose reduction

  • Yuhuan Chen
  • Qi Wang
  • Jianying Li
  • Yongjun Jia
  • Qi Yang
  • Taiping HeEmail author



To explore the use of two consecutive axial scans in triple-rule-out (TRO) examination on a 16 cm wide-detector CT for radiation dose reduction.

Materials and methods

Sixty TRO patients were assigned to either study group (Group A, n = 30) or control group (Group B, n = 30). Group A used a two-phasic contrast injection: 25mgI/kg/s for 12 s in 1st and at 3.0 ml/s injection rate for 7 s in 2nd phase. The pulmonary artery, coronary artery and aorta were scanned in succession with two axial scans using smart-coverage technique. Group B used the conventional protocol of scanning pulmonary arteries first in helical, followed by coronary arteries in axial and aorta in helical mode with contrast injection of 25mgI/kg/s for 14 s. All images were reconstructed with 80% ASIR-V. The qualitative and quantitative image assessment and effective dose of the two groups were statistically compared.


The demographic data and quantitative measurements and qualitative image scores between the two groups were statistically the same (p > 0.05). However, Group A reduced radiation dose by 52% (2.67 ± 0.98 mSv vs. 5.65 ± 1.37 mSv) (p < 0.001).


Using two consecutive axial scans in triple-rule-out on a 16 cm wide-detector CT reduces radiation dose while maintaining image quality compared with the conventional TRO protocol.

Key Points

• Triple-rule-out can be performed with two-axial scans on a wide-detector CT system.

• TRO with two-axial scans maintain image quality compared with conventional protocol.

• TRO with two-axial scans reduces 52% radiation dose over conventional protocol.


Chest pain Radiation dosage Diagnostic imaging Computed tomography angiography Tomography, X-ray computed 



Acute coronary syndrome


Aortic dissection


Adaptive statistical iterative reconstruction


Contrast-to-noise ratio


Computed tomography angiography


CT dose index


Display field of view


Dose-length product


Maximum intensity projection




Pulmonary thromboembolism




Standard deviation


Snapshot freeze




Volume rendering



The authors state that this work has not received any funding.

Compliance with ethical standards


The scientific guarantor of this publication is Taiping He.

Conflict of interest

The authors of this manuscript declare no conflict of interest exits in the submission of this manuscript.

Statistics and biometry

No complex statistical methods were necessary for this paper.

Informed consent

Written informed consent was obtained from all subjects (patients) in this study.

Ethical approval

Institutional Review Board approval was obtained.


• Prospective

• randomized controlled trial

• performed at one institution


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Copyright information

© European Society of Radiology 2018

Authors and Affiliations

  1. 1.Shaanxi University of Traditional Chinese MedicineXianyangChina
  2. 2.Department of RadiologyAffiliated Hospital of Shaanxi Chinese Medicine UniversityXianyangChina
  3. 3.Department of RadiologyChang’an HospitalXi’anChina
  4. 4.CT Research Center, GE Healthcare ChinaWuxiChina

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