title: Effect of the rate of gadolinium injection on magnetic resonance pulmonary perfusion imaging.
abstract: OBJECTIVE
  To determine whether the injection rate of contrast agent affects the dynamics of enhancement of the pulmonary parenchyma on magnetic resonance (MR) pulmonary perfusion imaging.
  
  
  METHODS
  Fifteen healthy volunteers underwent enhanced MR pulmonary perfusion imaging to evaluate the effects of different injection rates. Injection rates were 1, 3, or 5 mL/second. Regions of interest (ROIs) were chosen in the lung and aorta to analyze the change in signal intensity over time.
  
  
  RESULTS
  As the injection rate increased, the peak enhancement occurred significantly earlier (P = 0.0012), but the peak enhancement signal-to-noise ratio (SNR) value was not affected (P = 0.25). With the 3- and 5-mL/second injection rates, images of both the pulmonary circulation and systemic circulation were obtained separately. However, with 1 mL/second, higher enhancement of the aorta was overlapped with peak enhancement of the lung tissue.
  
  
  CONCLUSIONS
  The injection rate affects the enhancement profiles of the pulmonary parenchyma.
authors.affiliation: Department of Radiology, Teikyo University School of Medicine, Ichihara Hospital, Anesaki Ichihara Chiba, Japan. shinma@d9.dion.ne.jp
authors.forename: Shin
authors.initials: S
authors.lastname: Matsuoka
authors.forename: Katsuhiro
authors.initials: K
authors.lastname: Uchiyama
authors.forename: Hideki
authors.initials: H
authors.lastname: Shima
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Terakoshi
authors.forename: Sonomi
authors.initials: S
authors.lastname: Oishi
authors.forename: Yoko
authors.initials: Y
authors.lastname: Nojiri
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Ogata
mesh_terms: D000328:Adult; D003287:Contrast Media / Q000008:administration & dosage* / Q000493:pharmacokinetics; D019786:Gadolinium DTPA / Q000008:administration & dosage* / Q000493:pharmacokinetics; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007275:Injections, Intravenous / Q000379:methods*; D008168:Lung / Q000098:blood supply*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D018709:Statistics, Nonparametric; D013997:Time Factors
chemical_list: D003287:Contrast Media; C064925:gadodiamide; D019786:Gadolinium DTPA