title: 70-kVp High-pitch Computed Tomography Pulmonary Angiography with 40 mL Contrast Agent: Initial Experience.
abstract: OBJECTIVE
  To assess image quality, radiation dose, and diagnostic accuracy of 70-kVp high-pitch computed tomography pulmonary angiography (CTPA) using 40 mL contrast agent and sinogram affirmed iterative reconstruction (SAFIRE) compared to 100-kVp CTPA using 60 mL contrast agent and filtered back projection.
  
  
  METHODS
  Eighty patients underwent CTPA at either 70 kVp (group A, n = 40; 3.2 pitch, 40 mL contrast medium, and SAFIRE) or 100 kVp (group B, n = 40; 1.2 pitch, 60 mL contrast medium, and filtered back projection). Signal-to-noise ratio and contrast-to-noise ratio were calculated. Subjective image quality was evaluated using a five-grade scale, and diagnostic accuracy was assessed. Radiation doses were compared.
  
  
  RESULTS
  Computed tomography values, signal-to-noise ratio, and contrast-to-noise ratio of pulmonary arteries were higher in group A compared to group B (all P < 0.001). Subjective image quality showed no difference between the two groups (P = 0.559) with good interobserver agreement (κ = 0.647). No difference was found regarding diagnostic accuracy between the two groups (P > 0.05). The effective dose for group A was lower by 80% compared to group B (P < 0.001).
  
  
  CONCLUSIONS
  70-kVp high-pitch CTPA with reduced contrast media and SAFIRE provides comparable image quality and substantial radiation dose savings compared to a routine CTPA protocol.
authors.affiliation: Department of Medical Imaging, Jinling Hospital, Nanjing Clinical School, Southern Medical University, No.305, ZhongShan East Road, Nanjing, Jiangsu 210002, China.
authors.forename: Xie
authors.initials: X
authors.lastname: Li
authors.affiliation: Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210002, China.
authors.forename: Qian Qian
authors.initials: QQ
authors.lastname: Ni
authors.affiliation: Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210002, China; Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC 29401, USA.
authors.forename: U Joseph
authors.initials: UJ
authors.lastname: Schoepf
authors.affiliation: Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC 29401, USA; Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, 60590 Frankfurt, Germany.
authors.forename: Julian L
authors.initials: JL
authors.lastname: Wichmann
authors.affiliation: Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC 29401, USA.
authors.forename: Lloyd M
authors.initials: LM
authors.lastname: Felmly
authors.affiliation: Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210002, China.
authors.forename: Li
authors.initials: L
authors.lastname: Qi
authors.affiliation: Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210002, China.
authors.forename: Xiang
authors.initials: X
authors.lastname: Kong
authors.affiliation: Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210002, China.
authors.forename: Chang Sheng
authors.initials: CS
authors.lastname: Zhou
authors.affiliation: Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210002, China.
authors.forename: Song
authors.initials: S
authors.lastname: Luo
authors.affiliation: Department of Medical Imaging, Jinling Hospital, Nanjing Clinical School, Southern Medical University, No.305, ZhongShan East Road, Nanjing, Jiangsu 210002, China; Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210002, China. Electronic address: kevinzhlj@163.com.
authors.forename: Long Jiang
authors.initials: LJ
authors.lastname: Zhang
authors.affiliation: Department of Medical Imaging, Jinling Hospital, Nanjing Clinical School, Southern Medical University, No.305, ZhongShan East Road, Nanjing, Jiangsu 210002, China; Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210002, China. Electronic address: cjr.luguangming@vip.163.com.
authors.forename: Guang Ming
authors.initials: GM
authors.lastname: Lu
mesh_terms: D000328:Adult; D000368:Aged; D000792:Angiography / Q000379:methods*; D003287:Contrast Media / Q000008:administration & dosage; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011651:Pulmonary Artery / Q000000981:diagnostic imaging; D011655:Pulmonary Embolism / Q000175:diagnosis*; D011829:Radiation Dosage; D011857:Radiographic Image Interpretation, Computer-Assisted; D012815:Signal Processing, Computer-Assisted; D059629:Signal-To-Noise Ratio; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D003287:Contrast Media
keywords: Computed tomography pulmonary angiography; Contrast material; Iterative reconstruction; Pulmonary embolism; Radiation dose