title: Recent Update on Radiation Dose Assessment for the State-of-the-Art Coronary Computed Tomography Angiography Protocols.
abstract: OBJECTIVE
  This study aimed to measure the absorbed doses in selected organs for prospectively ECG-triggered coronary computed tomography angiography (CCTA) using five different generations CT scanners in a female adult anthropomorphic phantom and to estimate the effective dose (HE).
  
  
  METHODS
  Prospectively ECG-triggered CCTA was performed using five commercially available CT scanners: 64-detector-row single source CT (SSCT), 2 × 32-detector-row-dual source CT (DSCT), 2 × 64-detector-row DSCT and 320-detector-row SSCT scanners. Absorbed doses were measured in 34 organs using pre-calibrated optically stimulated luminescence dosimeters (OSLDs) placed inside a standard female adult anthropomorphic phantom. HE was calculated from the measured organ doses and compared to the HE derived from the air kerma-length product (PKL) using the conversion coefficient of 0.014 mSv∙mGy-1∙cm-1 for the chest region.
  
  
  RESULTS
  Both breasts and lungs received the highest radiation dose during CCTA examination. The highest HE was received from 2 × 32-detector-row DSCT scanner (6.06 ± 0.72 mSv), followed by 64-detector-row SSCT (5.60 ± 0.68 and 5.02 ± 0.73 mSv), 2 × 64-detector-row DSCT (1.88 ± 0.25 mSv) and 320-detector-row SSCT (1.34 ± 0.48 mSv) scanners. HE calculated from the measured organ doses were about 38 to 53% higher than the HE derived from the PKL-to-HE conversion factor.
  
  
  CONCLUSIONS
  The radiation doses received from a prospectively ECG-triggered CCTA are relatively small and are depending on the scanner technology and imaging protocols. HE as low as 1.34 and 1.88 mSv can be achieved in prospectively ECG-triggered CCTA using 320-detector-row SSCT and 2 × 64-detector-row DSCT scanners.
authors.affiliation: Department of Biomedical Imaging, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: Sock Keow
authors.initials: SK
authors.lastname: Tan
authors.affiliation: Department of Biomedical Imaging, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: Chai Hong
authors.initials: CH
authors.lastname: Yeong
authors.affiliation: Department of Biomedical Imaging, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: Kwan Hoong
authors.initials: KH
authors.lastname: Ng
authors.affiliation: Department of Biomedical Imaging, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: Yang Faridah
authors.initials: YF
authors.lastname: Abdul Aziz
authors.affiliation: Department of Medical Radiation Sciences, Curtin University, Perth, WA 6845, Australia.
authors.forename: Zhonghua
authors.initials: Z
authors.lastname: Sun
mesh_terms: D000072226:Computed Tomography Angiography / Q000379:methods; D017023:Coronary Angiography / Q000379:methods; D005260:Female; D006801:Humans; D009928:Organ Specificity / Q000528:radiation effects; D019047:Phantoms, Imaging; D011829:Radiation Dosage; D011874:Radiometry; D015898:Tomography Scanners, X-Ray Computed