title: Comparison of two different injection rates of gadoxetic acid for arterial phase MRI of the liver.
abstract: OBJECTIVE
  To compare two different injection rates for gadoxetic acid-enhanced hepatic arterial phase images on hepatic dynamic MRI.
  
  
  METHODS
  Hepatic arterial phase images were obtained after an intravenous bolus injection of gadoxetic acid at a rate of 1 mL/second in 62 patients and 2 mL/second in 64 patients on a 3 Tesla MR scanner using a test-bolus injection method. The signal-to-noise ratios (SNR) of the liver, portal vein, hepatic vein, aorta, spleen and pancreas were measured. The contrast-to-noise ratio (CNR) of hypervascular hepatic tumors was calculated. Two radiologists independently scored items to evaluate image quality of hepatic arterial phase and detected hypervascular hepatocellular carcinoma (HCC).
  
  
  RESULTS
  The SNR of the aorta on the arterial phase images was significantly higher in the 1 mL/second group (235.43 +/- 82.59) than in the 2 mL/second group (190.94 +/- 96.90, P < 0.05). The SNRs of the liver, spleen and pancreas, the CNRs of hypervascular hepatic tumors, the detection rate of hypervascular HCC and subjective ratings for the optimal arterial enhancement were comparable between the two groups.
  
  
  CONCLUSIONS
  Injection rates of 2 mL/second and 1 mL/second provided comparable image qualities on arterial phase images of hepatic dynamic MRI using gadoxetic acid.
authors.affiliation: Department of Radiology and Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Sang-Hoon
authors.initials: SH
authors.lastname: Chung
authors.forename: Myeong-Jin
authors.initials: MJ
authors.lastname: Kim
authors.forename: Jin-Young
authors.initials: JY
authors.lastname: Choi
authors.forename: Hye-Suk
authors.initials: HS
authors.lastname: Hong
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003287:Contrast Media / Q000008:administration & dosage; D005260:Female; D019786:Gadolinium DTPA / Q000008:administration & dosage*; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007269:Injections, Intra-Arterial; D008099:Liver / Q000473:pathology*; D008113:Liver Neoplasms / Q000473:pathology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D003287:Contrast Media; C073590:gadolinium ethoxybenzyl DTPA; D019786:Gadolinium DTPA