title: Individually adapted tube current selection and contrast medium injection protocol of coronary CT angiography based on test bolus parameters: a feasibility study.
abstract: BACKGROUND
  Test bolus is mostly used to determine the starting point of a full cardiac scanning with respect to injection of a larger bolus of contrast material. So far there are limited data demonstrating the feasibility of using information obtained from a test bolus to adjust contrast delivery protocols and tube current individually during coronary computed tomography angiography (CCTA).
  
  
  OBJECTIVE
  To evaluate the feasibility of individually adapted tube current selection and contrast injection protocols of CCTA based on test bolus parameters.
  
  
  METHODS
  Test bolus followed by CCTA was performed in 93 patients at 100 kV and in 81 patients at 120 kV, respectively. Simulated attenuation of the descending aorta (SimDA) of CCTA was calculated at a fixed contrast injection rate of 4 mL/s. Univariate and multivariate comparisons were performed to identify associations of SimDA and image noise of CCTA (NoiseCCTA) with test bolus information and patient-related factors including body weight (BW), body mass index (BMI), and body surface area (BSA).
  
  
  RESULTS
  Compared with BW, BMI, and BSA, SimDA was more closely related to the peak time of left ventricle and peak enhancement of right ventricle obtained from test bolus (r = 0.495 and r = 0.642 for 100 and 120 kV protocol, respectively). Similarly, NoiseTB was much more closely related to NoiseCCTA (r = 0.740 and r = 0.630 for 100 and 120 kV protocol, respectively) when compared with BW, BMI, and BSA.
  
  
  CONCLUSIONS
  It is feasible to individually adapt tube current and contrast injection protocol of CCTA based on the information of test bolus.
authors.affiliation: Department of Radiology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, PR China.
authors.forename: Xiaomei
authors.initials: X
authors.lastname: Zhu
authors.affiliation: Department of Radiology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, PR China.
authors.forename: Zhaofei
authors.initials: Z
authors.lastname: Shi
authors.affiliation: Department of Radiology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, PR China.
authors.forename: Yinsu
authors.initials: Y
authors.lastname: Zhu
authors.affiliation: Department of Radiology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, PR China.
authors.forename: Wangyan
authors.initials: W
authors.lastname: Liu
authors.affiliation: Laboratory of Image Science & Technology, School of Computer Science and Engineering, Southeast University, Nanjing, Jiangsu, PR China.
authors.forename: Guanyu
authors.initials: G
authors.lastname: Yang
authors.affiliation: Department of Radiology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, PR China.
authors.forename: Tongfu
authors.initials: T
authors.lastname: Yu
authors.affiliation: Department of Radiology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, PR China Lijun.tang@hotmail.com.
authors.forename: Lijun
authors.initials: L
authors.lastname: Tang
authors.affiliation: Department of Radiology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, PR China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Xu
mesh_terms: D015992:Body Mass Index; D001835:Body Weight; D002985:Clinical Protocols; D003287:Contrast Media / Q000008:administration & dosage*; D017023:Coronary Angiography / Q000379:methods*; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D007267:Injections; D008297:Male; D008875:Middle Aged; D057285:Precision Medicine; D011446:Prospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D003287:Contrast Media
keywords: Coronary CT angiography; contrast enhancement; descending aorta; image noise; test bolus