Radiation dose reduction method combining the ECG-Edit function and high helical pitch in retrospectively-gated CT angiography

T Masuda; Y Funama; T Nakaura; T Sato; T Okimoto; R Gotanda; K Arao; H Imaizumi; S Arao; A Ono; J Hiratsuka; K Awai

doi:10.1016/j.radi.2022.03.004

Radiation dose reduction method combining the ECG-Edit function and high helical pitch in retrospectively-gated CT angiography

Radiography (Lond). 2022 Aug;28(3):766-771. doi: 10.1016/j.radi.2022.03.004. Epub 2022 Apr 12.

Authors

T Masuda¹, Y Funama², T Nakaura³, T Sato⁴, T Okimoto⁵, R Gotanda⁶, K Arao⁶, H Imaizumi⁶, S Arao⁶, A Ono⁶, J Hiratsuka⁶, K Awai⁷

Affiliations

¹ Department of Radiological Technology, Faculty of Health Science and Technology, Kawasaki University of Medical Welfare, 288 Matsushima, Kurashiki-city, Okayama 701-0193, Japan. Electronic address: takanorimasuda@yahoo.co.jp.
² Department of Medical Physics, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan.
³ Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1 Honjo, Kumamoto 860-8556, Japan.
⁴ Department of Diagnostic Radiology, Tsuchiya General Hospital, Nakajima-cho 3-30, Naka-ku, Hiroshima 730-8655, Japan.
⁵ Department of Cardiovascular Internal Medicine, Edogawa Hospital, Tokyo, Japan.
⁶ Department of Radiological Technology, Faculty of Health Science and Technology, Kawasaki University of Medical Welfare, 288 Matsushima, Kurashiki-city, Okayama 701-0193, Japan.
⁷ Department of Diagnostic Radiology, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima, Japan.

PMID: 35428572
DOI: 10.1016/j.radi.2022.03.004

Abstract

Introduction: The purpose of this study was to demonstrate that dose reduction does not compromise image quality when combining high helical pitch (HP) and the ECG-Edit function during low HP retrospectively gated computed tomography angiography (CTA).

Methods: This study made use of a pulsating cardiac phantom (ALPHA 1 VTPC). The heart rate (HR) of the cardiac phantom was changed in five intervals, every 5 beats per minute (bpm), from 40 to 60 bpm. Evaluation of a range of HR was important because data loss might occur when combining a low HR and high HP. We performed retrospectively gated CTA scans five times using a low HP (0.16) and high HP (0.24), for each of the five HR intervals, using a 64-detector row CT scanner. The CT volume dose index (CTDI_vol) was recorded from the CT console of each scan. For the images with data loss, data were repaired using the ECG-Edit function. We compared the CTDI_vol, estimated cardiac phantom volume, and the visualization of the coronary ladder phantom between HP 0.16, with or without repaired HP 0.24, using the ECG-Edit function.

Results: Data loss occurred with a HR of 40 bpm and 45 bpm when using HP 0.24. The CTDI_vol was reduced by approximately 33% with HP 0.24 when compared with HP 0.16. There were no significant differences in the mean cardiac motion phantom volume and visualization scores between HP 0.16 and with and without repaired HP 0.24 using the ECG-Edit function (p < 0.05).

Conclusion: The ECG-Edit function is potential useful for repairing the lost data in patients with a low HR, and when combined with a high HP, it is possible to reduce the radiation dose by approximately 33%.

Implications for practice: The ECG-Edit function and high HP may be a viable option in pediatric CTA studies.

Keywords: CT angiography; Electrocardiogram edit function; High helical pitch; MDCT; Radiation dose reduction.

MeSH terms

Child
Computed Tomography Angiography*
Coronary Angiography / methods
Drug Tapering
Electrocardiography* / methods
Humans
Radiation Dosage
Retrospective Studies