title: Can MR fluoroscopic triggering technique and slow rate injection provide appropriate arterial phase images with reducing artifacts on gadoxetic acid-DTPA (Gd-EOB-DTPA)-enhanced hepatic MR imaging?
abstract: OBJECTIVE
  To evaluate whether using MR fluoroscopic triggering technique and slow rate injection improves the quality of arterial phase images in gadoxetic acid-DTPA-enhanced (Gd-EOB-DTPA) MR imaging because of proper acquisition timing and reduction of artifacts.
  
  
  METHODS
  Two hundred sixteen patients undergoing examination for liver diseases were retrospectively reviewed. All MR images were obtained with two Gd-EOB-DTPA injection protocols: (i) a combination protocol, in which the MR fluoroscopic triggering technique and slow rate injection (1 mL/s) were used; and for comparison, (ii) a conventional protocol, in which adjusted fixed scan delay and ordinary rate injection (2 mL/s) were adopted. Signal-to-noise ratio (SNR) of aorta, portal vein, and liver parenchyma on arterial phase images were calculated. Two blinded readers independently evaluated the obtained arterial phase images in terms of acquisition timing and degree of artifacts.
  
  
  RESULTS
  The SNRs of aorta and portal vein on arterial phase images were significantly higher in the combination protocol group (aorta/portal: 221.9 +/- 91.9/197.1 +/- 89.8) than that in the conventional protocol group (aorta/portal: 169.8 +/- 97.4/92.7 +/- 48.5) (P < 0.05). The acquisition timing for arterial phase images with the combination protocol was significantly better than that with the conventional protocol (P < 0.01). The image quality of the combination protocol was significantly higher than that of the conventional protocol (P < 0.01). The occurrence rate of moderate or severe degree of artifacts in the conventional protocol (38.0%) was more prominent than that in the combination protocol (18.5%).
  
  
  CONCLUSIONS
  The combination of the MR fluoroscopic triggering technique and slow rate injection provides proper arterial phase images and reduces the artifacts in Gd-EOB-DTPA MR imaging.
authors.affiliation: Department of Radiology, University of Brescia, Spedali Civili di Brescia, Italy. karate.b@gmail.com
authors.forename: Hiroki
authors.initials: H
authors.lastname: Haradome
authors.forename: Luigi
authors.initials: L
authors.lastname: Grazioli
authors.forename: Mika
authors.initials: M
authors.lastname: Tsunoo
authors.forename: Rita
authors.initials: R
authors.lastname: Tinti
authors.forename: Barbara
authors.initials: B
authors.lastname: Frittoli
authors.forename: Sebastiana
authors.initials: S
authors.lastname: Gambarini
authors.forename: Mario
authors.initials: M
authors.lastname: Morone
authors.forename: Utaroh
authors.initials: U
authors.lastname: Motosugi
authors.forename: Stefano
authors.initials: S
authors.lastname: Colagrande
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001158:Arteries / Q000473:pathology*; D016477:Artifacts; D003287:Contrast Media / Q000494:pharmacology*; D005260:Female; D005471:Fluoroscopy / Q000379:methods*; D019786:Gadolinium DTPA / Q000494:pharmacology*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D015203:Reproducibility of Results
chemical_list: D003287:Contrast Media; C073590:gadolinium ethoxybenzyl DTPA; D019786:Gadolinium DTPA