title: Bolus shaping of contrast medium to adapt k-space sampling: adjusting injection protocol of magnetic resonance angiography for optimal images in a 3-T system.
abstract: OBJECTIVE
  To explore the possibility of shaping bolus of contrast medium to adapt k-space sampling to improve image quality in a 3-T system.
  
  
  METHODS
  Eighty patients suspected of having renal arterial disease or atherosclerosis were divided into four groups and underwent imaging with different high-spatial-resolution three-dimensional contrast-enhanced magnetic resonance angiography (MRA) scanning and injection protocol combinations. A group of 20 patients were injected single-dose contrast medium with a centric view ordering for k-space filling. Another group of 20 patients underwent MRA with double-dose and centric-view ordering. The bolus of contrast medium was shaped by adjusting injection protocol to adapt centric and sequential view ordering of sampling k-space, respectively, for other two groups. Then, the quality of image got with different protocols combination was compared, and the dose of contrast medium used in latter two groups was compared with single- and double-dose prescription basing on body weight.
  
  
  RESULTS
  Bolus shaped adapting to centric view ordering and sequential view ordering brings more homogeneous vessel signal. Individualized dose is lower than the double dose but higher than the single dose. Dose does not necessarily correlate with body weight.
  
  
  CONCLUSIONS
  Under certain scanning protocol, appropriate shape of contrast medium passing through target vessel leads to higher-quality image and save contrast medium.
authors.affiliation: Department of Radiology, Beijing Institute of Heart Lung and Blood Vessel Disease & Beijing Anzhen Hospital of Capital University of Medical Science, Anding men wai, Chaoyang District, Beijing 100029, China.
authors.forename: Biao
authors.initials: B
authors.lastname: Lu
authors.forename: Zhao-Qi
authors.initials: ZQ
authors.lastname: Zhang
authors.forename: Zhan-Ming
authors.initials: ZM
authors.lastname: Fan
authors.forename: Kai
authors.initials: K
authors.lastname: Lin
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003287:Contrast Media / Q000008:administration & dosage*; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007269:Injections, Intra-Arterial / Q000379:methods; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008875:Middle Aged; D016491:Peripheral Vascular Diseases / Q000175:diagnosis*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D003287:Contrast Media