title: Time-resolved contrast-enhanced three-dimensional pulmonary MR-angiography: 1.0 M gadobutrol vs. 0.5 M gadopentetate dimeglumine.
abstract: OBJECTIVE
  To compare contrast characteristics and image quality of 1.0 M gadobutrol with 0.5 M Gd-DTPA for time-resolved three-dimensional pulmonary magnetic resonance angiography (MRA).
  
  
  METHODS
  Thirty-one patients and five healthy volunteers were examined with a contrast-enhanced time-resolved pulmonary MRA protocol (fast low-angle shot [FLASH] three-dimensional, TR/TE = 2.2/1.0 msec, flip angle: 25 degrees, scan time per three-dimensional data set = 5.6 seconds). Patients were randomized to receive either 0.1 mmol/kg body weight (bw) or 0.2 mmol/kg bw gadobutrol, or 0.2 mmol/kg bw Gd-DTPA. Volunteers were examined three times, twice with 0.2 mmol/kg bw gadobutrol using two different flip angles and once with 0.2 mmol/kg bw Gd-DTPA. All contrast injections were performed at a rate of 5 mL/second. Image analysis included signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) measurements in lung arteries and veins, as well as a subjective analysis of image quality.
  
  
  RESULTS
  In patients, significantly higher SNR and CNR were observed with Gd-DTPA compared to both doses of gadobutrol (SNR: 35-42 vs.17-25; CNR 33-39 vs. 16-23; P < or = 0.05). No relevant differences were observed between 0.1 mmol/kg bw and 0.2 mmol/kg bw gadobutrol. In volunteers, gadobutrol and Gd-DTPA achieved similar SNR and CNR. A significantly higher SNR and CNR was observed for gadobutrol-enhanced MRA with an increased flip angle of 40 degrees. Image quality was rated equal for both contrast agents.
  
  
  CONCLUSIONS
  No relevant advantages of 1.0 M gadobutrol over 0.5 M Gd-DTPA were observed for time-resolved pulmonary MRA in this study. Potential explanations are T2/T2*-effects caused by the high intravascular concentration when using high injection rates.
authors.affiliation: Department of Radiology, Deutsches Krebsforschungszentrum, Heidelberg, Germany. c.fink@dkfz.de
authors.forename: Christian
authors.initials: C
authors.lastname: Fink
authors.forename: Michael
authors.initials: M
authors.lastname: Bock
authors.forename: Fabian
authors.initials: F
authors.lastname: Kiessling
authors.forename: Matthias Philipp
authors.initials: MP
authors.lastname: Lichy
authors.forename: Radko
authors.initials: R
authors.lastname: Krissak
authors.forename: Ivan
authors.initials: I
authors.lastname: Zuna
authors.forename: Astrid
authors.initials: A
authors.lastname: Schmähl
authors.forename: Stefan
authors.initials: S
authors.lastname: Delorme
authors.forename: Hans-Ulrich
authors.initials: HU
authors.lastname: Kauczor
mesh_terms: D000328:Adult; D000368:Aged; D003287:Contrast Media / Q000008:administration & dosage; D004305:Dose-Response Relationship, Drug; D005260:Female; D019786:Gadolinium DTPA / Q000008:administration & dosage; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D007275:Injections, Intravenous; D008171:Lung Diseases / Q000175:diagnosis; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009942:Organometallic Compounds / Q000008:administration & dosage; D011651:Pulmonary Artery / Q000033:anatomy & histology; D011652:Pulmonary Circulation / Q000502:physiology*; D011667:Pulmonary Veins / Q000033:anatomy & histology; D012016:Reference Values; D018709:Statistics, Nonparametric; D013997:Time Factors
chemical_list: D003287:Contrast Media; D009942:Organometallic Compounds; C090600:gadobutrol; D019786:Gadolinium DTPA