title: Image quality at low tube voltage (70 kV) and sinogram-affirmed iterative reconstruction for computed tomography in infants with congenital heart disease.
abstract: BACKGROUND
  Lower tube voltage has advantages for CT angiography, such as improved contrast
  
  
  OBJECTIVE
  To evaluate the image quality of low-voltage (70 kV) CT for congenital heart disease and the ability of sinogram-affirmed iterative reconstruction to improve image quality.
  
  
  METHODS
  Forty-six children with congenital heart disease (median age: 109 days) were examined using dual-source CT. Scans were performed at 80 kV and 70 kV in 21 and 25 children, respectively. A nonionic iodinated contrast medium (300 mg I/ml) was used for the 80-kV protocol. The contrast medium was diluted to 75% (225 mgI/mL) with saline for the 70-kV protocol. Image noise was measured in the two protocols for each group by extracting the standard deviations of a region of interest placed on the descending aorta. We then determined whether sinogram-affirmed iterative reconstruction reduced the image noise at 70 kV.
  
  
  RESULTS
  There was more noise at 70 kV than at 80 kV (29 ± 12 vs 20 ± 4.8; P < 0.01). Sinogram-affirmed iterative reconstruction with grade 4 strength settings improved the noise (20 ± 5.9; P < 0.01) for the 70-kV group.
  
  
  CONCLUSIONS
  Sinogram-affirmed iterative reconstruction improved the image quality of CT in congenital heart disease.
authors.affiliation: Department of Radiology, Nagoya City University Graduate School of Medical Sciences, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya, Japan, lmloltlolol@gmail.com.
authors.forename: Motoo
authors.initials: M
authors.lastname: Nakagawa
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Ozawa
authors.forename: Keita
authors.initials: K
authors.lastname: Sakurai
authors.forename: Masashi
authors.initials: M
authors.lastname: Shimohira
authors.forename: Kazuya
authors.initials: K
authors.lastname: Ohashi
authors.forename: Miki
authors.initials: M
authors.lastname: Asano
authors.forename: Sachiko
authors.initials: S
authors.lastname: Yamaguchi
authors.forename: Yuta
authors.initials: Y
authors.lastname: Shibamoto
mesh_terms: D003287:Contrast Media; D017023:Coronary Angiography / Q000379:methods*; D005260:Female; D006330:Heart Defects, Congenital / Q000000981:diagnostic imaging*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D011829:Radiation Dosage; D011856:Radiographic Image Enhancement; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods*; D015203:Reproducibility of Results; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D003287:Contrast Media