title: Image Quality and Radiation Dose of CT Coronary Angiography with Automatic Tube Current Modulation and Strong Adaptive Iterative Dose Reduction Three-Dimensional (AIDR3D).
abstract: OBJECTIVE
  To investigate image quality and radiation dose of CT coronary angiography (CTCA) scanned using automatic tube current modulation (ATCM) and reconstructed by strong adaptive iterative dose reduction three-dimensional (AIDR3D).
  
  
  METHODS
  Eighty-four consecutive CTCA patients were collected for the study. All patients were scanned using ATCM and reconstructed with strong AIDR3D, standard AIDR3D and filtered back-projection (FBP) respectively. Two radiologists who were blinded to the patients' clinical data and reconstruction methods evaluated image quality. Quantitative image quality evaluation included image noise, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR). To evaluate image quality qualitatively, coronary artery is classified into 15 segments based on the modified guidelines of the American Heart Association. Qualitative image quality was evaluated using a 4-point scale. Radiation dose was calculated based on dose-length product.
  
  
  RESULTS
  Compared with standard AIDR3D, strong AIDR3D had lower image noise, higher SNR and CNR, their differences were all statistically significant (P<0.05); compared with FBP, strong AIDR3D decreased image noise by 46.1%, increased SNR by 84.7%, and improved CNR by 82.2%, their differences were all statistically significant (P<0.05 or 0.001). Segments with diagnostic image quality for strong AIDR3D were 336 (100.0%), 486 (96.4%), and 394 (93.8%) in proximal, middle, and distal part respectively; whereas those for standard AIDR3D were 332 (98.8%), 472 (93.7%), 378 (90.0%), respectively; those for FBP were 217 (64.6%), 173 (34.3%), 114 (27.1%), respectively; total segments with diagnostic image quality in strong AIDR3D (1216, 96.5%) were higher than those of standard AIDR3D (1182, 93.8%) and FBP (504, 40.0%); the differences between strong AIDR3D and standard AIDR3D, strong AIDR3D and FBP were all statistically significant (P<0.05 or 0.001). The mean effective radiation dose was (2.55±1.21) mSv.
  
  
  CONCLUSIONS
  Compared with standard AIDR3D and FBP, CTCA with ATCM and strong AIDR3D could significantly improve both quantitative and qualitative image quality.
authors.affiliation: Department of Radiology, The Sixth Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China.|Department of Radiology, Chongqing Cancer Institute, Chongqing, China.
authors.forename: Hesong
authors.initials: H
authors.lastname: Shen
authors.affiliation: Imaging Center, The First People's Hospital of Kashi Area, Xinjiang, China.
authors.forename: Guochao
authors.initials: G
authors.lastname: Dai
authors.affiliation: Department of Radiology, The Sixth Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China.
authors.forename: Mingyue
authors.initials: M
authors.lastname: Luo
authors.affiliation: Research Center of Biomedical Engineering, Graduate School at Shenzhen, Tsinghua University, Shenzhen, Guangdong, China.
authors.forename: Chaijie
authors.initials: C
authors.lastname: Duan
authors.affiliation: Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States.
authors.forename: Wenli
authors.initials: W
authors.lastname: Cai
authors.affiliation: Department of Radiology, The Sixth Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China.
authors.forename: Dan
authors.initials: D
authors.lastname: Liang
authors.affiliation: Department of Radiology, The Sixth Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China.
authors.forename: Xinhua
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Radiology, The Sixth Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China.
authors.forename: Dongyun
authors.initials: D
authors.lastname: Zhu
authors.affiliation: Department of Radiology, The Sixth Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China.
authors.forename: Wenru
authors.initials: W
authors.lastname: Li
authors.affiliation: Department of Radiology, The Sixth Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China.
authors.forename: Jianping
authors.initials: J
authors.lastname: Qiu
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D001331:Automation; D003287:Contrast Media / Q000737:chemistry; D017023:Coronary Angiography / Q000379:methods*; D003331:Coronary Vessels / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D011446:Prospective Studies; D011829:Radiation Dosage; D011857:Radiographic Image Interpretation, Computer-Assisted; D011871:Radiology / Q000379:methods*; D059629:Signal-To-Noise Ratio; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D003287:Contrast Media