title: Image quality of ct angiography using model-based iterative reconstruction in infants with congenital heart disease: Comparison with filtered back projection and hybrid iterative reconstruction.
abstract: OBJECTIVE
  To compare the image quality, rate of coronary artery visualization and diagnostic accuracy of 256-slice multi-detector computed tomography angiography (CTA) with prospective electrocardiographic (ECG) triggering at a tube voltage of 80kVp between 3 reconstruction algorithms (filtered back projection (FBP), hybrid iterative reconstruction (iDose4) and iterative model reconstruction (IMR)) in infants with congenital heart disease (CHD).
  
  
  METHODS
  Fifty-one infants with CHD who underwent cardiac CTA in our institution between December 2014 and March 2015 were included. The effective radiation doses were calculated. Imaging data were reconstructed using the FBP, iDose4and IMR algorithms. Parameters of objective image quality (noise, signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR)); subjective image quality (overall image quality, image noise and margin sharpness); coronary artery visibility; and diagnostic accuracy for the three algorithms were measured and compared.
  
  
  RESULTS
  The mean effective radiation dose was 0.61±0.32 mSv. Compared to FBP and iDose4, IMR yielded significantly lower noise (P<0.01), higher SNR and CNR values (P<0.01), and a greater subjective image quality score (P<0.01). The total number of coronary segments visualized was significantly higher for both iDose4and IMR than for FBP (P=0.002 and P=0.025, respectively), but there was no significant difference in this parameter between iDose4and IMR (P=0.397). There was no significant difference in the diagnostic accuracy between the FBP, iDose4and IMR algorithms (χ2=0.343, P=0.842).
  
  
  CONCLUSIONS
  For infants with CHD undergoing cardiac CTA, the IMR reconstruction algorithm provided significantly increased objective and subjective image quality compared with the FBP and iDose4algorithms. However, IMR did not improve the diagnostic accuracy or coronary artery visualization compared with iDose4.
authors.affiliation: Southern Medical University, Guangzhou, Guangdong, China; Department of Radiology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong, China; Department of Catheterization Lab, Guangdong Cardiovascular Institute, Guangdong Provincial Key Laboratory of South China Structural Heart Disease, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong, China. Electronic address: jiaqianjun@126.com.
authors.forename: Qianjun
authors.initials: Q
authors.lastname: Jia
authors.affiliation: Department of Cardiac Surgery, Guangdong Cardiovascular Institute, Guangdong Provincial Key Laboratory of South China Structural Heart Disease, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong, China. Electronic address: zhuangjian5413@tom.com.
authors.forename: Jian
authors.initials: J
authors.lastname: Zhuang
authors.affiliation: Department of Radiology, Shenzhen Second People's Hospital, Shenzhen, Guangdong, China. Electronic address: 81711587@qq.com.
authors.forename: Jun
authors.initials: J
authors.lastname: Jiang
authors.affiliation: Department of Catheterization Lab, Guangdong Cardiovascular Institute, Guangdong Provincial Key Laboratory of South China Structural Heart Disease, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong, China. Electronic address: 970872804@qq.com.
authors.forename: Jiahua
authors.initials: J
authors.lastname: Li
authors.affiliation: Department of Catheterization Lab, Guangdong Cardiovascular Institute, Guangdong Provincial Key Laboratory of South China Structural Heart Disease, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong, China; Southern Medical University, Guangzhou, Guangdong, China. Electronic address: huangmeiping_vip@163.com.
authors.forename: Meiping
authors.initials: M
authors.lastname: Huang
authors.affiliation: Department of Radiology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong, China; Southern Medical University, Guangzhou, Guangdong, China. Electronic address: cjr.lchh@vip.163.com.
authors.forename: Changhong
authors.initials: C
authors.lastname: Liang
mesh_terms: D000465:Algorithms; D000072226:Computed Tomography Angiography; D017023:Coronary Angiography / Q000379:methods; D003331:Coronary Vessels / Q000000981:diagnostic imaging; D004562:Electrocardiography / Q000379:methods; D005260:Female; D006330:Heart Defects, Congenital / Q000000981:diagnostic imaging*; D006801:Humans; D007223:Infant; D008297:Male; D008962:Models, Theoretical; D061330:Multidetector Computed Tomography / Q000379:methods; D011446:Prospective Studies; D011829:Radiation Dosage; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods; D015203:Reproducibility of Results; D059629:Signal-To-Noise Ratio
keywords: Congenital heart disease; Hybrid iterative reconstruction; Iterative model reconstruction; Multidetector CT