title: Low dose dual-source CT angiography in infants with complex congenital heart disease: a randomized study.
abstract: OBJECTIVE
  To investigate the radiation dose and image quality of prospective ECG-triggering dual-source CT angiography in infants with complex congenital heart disease (CHD) in comparison with retrospective ECG-gated scanning.
  
  
  METHODS
  Ninety-six infants less than 1 year old (60/36 male/female, age: 4.8 ± 2.7 months, weight: 5.8 ± 1.8 kg) with complex CHD were enrolled. Three image acquisition protocols were set: group 1: 80 kV, 100 mA, retrospective ECG-gated protocol; group 2: 80 kV, 100 mA, prospective ECG-triggering protocol with acquisition window of 380 ms; group 3: 80 kV, 100 mA, prospective ECG-triggering protocol with acquisition window of 200 ms. Patients were selected to any one of the protocols randomly. The signal-to-noise ratios (SNR) were calculated in the ascending aorta and the pulmonary artery trunk. Image quality was assessed by a five-point score. A score of <3 represents non-diagnostic. Effective radiation dose (ED) was calculated.
  
  
  RESULTS
  Image quality score of groups 1, 2 and 3 were 4.1 ± 0.4, 4.0 ± 0.6 and 4.2 ± 0.6 (p = 0.224). SNR of ascending aorta and pulmonary artery trunk among them had no statistical difference (all p>0.05). The average ED (median) of groups 1, 2 and 3 were 1.17 ± 0.07 mSv (1.25 mSv), 0.72 ± 0.24 mSv (0.78 mSv) and 0.48 ± 0.41 mSv (0.39 mSv). Any two of the three groups had significant differences (all p<0.001).
  
  
  CONCLUSIONS
  Prospective ECG-triggering DSCT angiography associated with a significantly lower ED than retrospective protocol, while maintaining image quality for diagnosis. Prospective ECG-triggering DSCT angiography could be used as a very important second-line diagnostic tool in infants with complex CHD.
authors.affiliation: Department of Radiology, Cardiovascular Institute and Fu Wai Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, #167 Bei-Li-Shi Street, Beijing 100037, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Gao
authors.forename: Bin
authors.initials: B
authors.lastname: Lu
authors.forename: Zhihui
authors.initials: Z
authors.lastname: Hou
authors.forename: Fangfang
authors.initials: F
authors.lastname: Yu
authors.forename: Huili
authors.initials: H
authors.lastname: Cao
authors.forename: Lei
authors.initials: L
authors.lastname: Han
authors.forename: Runze
authors.initials: R
authors.lastname: Wu
mesh_terms: D055424:Cardiac-Gated Imaging Techniques; D003287:Contrast Media; D017023:Coronary Angiography / Q000379:methods*; D004452:Echocardiography; D005260:Female; D006330:Heart Defects, Congenital / Q000000981:diagnostic imaging*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D011829:Radiation Dosage; D011857:Radiographic Image Interpretation, Computer-Assisted; D018709:Statistics, Nonparametric; D014057:Tomography, X-Ray Computed / Q000379:methods*; D014283:Triiodobenzoic Acids
chemical_list: D003287:Contrast Media; D014283:Triiodobenzoic Acids; C044834:iodixanol