title: Focal liver lesions: whether a standard dose (0.05 mmol/kg) gadobenate dimeglumine can provide the same diagnostic data as the 0.1 mmol/kg dose.
abstract: OBJECTIVE
  Gadobenate dimeglumine (Gd-BOPTA) is a liver-specific contrast agent also showing a distribution in the extracellular compartment which is recommended to be used at standard dose (0.05 mmol/kg) in magnetic resonance imaging (MRI) of liver lesions. However, its use at 0. 1mmol/kg is gradually increasing in recent clinical practice. Which dose should we use in routine MRI of liver lesions from now on? This study investigated the efficacy of Gd-BOPTA at a standard dose versus 0.1 mmol/kg dose in demonstrating diagnostic data in MRI of focal liver lesions.
  
  
  METHODS
  The study included 47 patients with focal liver lesions. Twenty-two patients received standard dose and 25 patients received 0.1 mmol/kg dose Gd-BOPTA intravenously. MRI of both groups was carried out with T1-A FLASH-2D and T2-A TURBO spin echo before contrast injection and T1-A FLASH-2D sequences in dynamic and late phase (90th minute) after the contrast injection. The lesion conspicuity for each image was evaluated qualitatively. Liver signal to noise ratio (SNR), absolute lesion-liver contrast to noise ratio (CNR), mean lesion-liver CNR and contrast enhancement rate of the liver obtained from both groups were compared quantitatively.
  
  
  RESULTS
  While liver contrast enhancement rate in the group receiving standard dose Gd-BOPTA were 41%+/-42 in the arterial phase, 66%+/-58 in the portal phase, 45%+/-45 in the venous phase and 42%+/-88 in the late phase, these values were 43%+/-59, 86%+/-73, 63%+/-75 and 61%+/-105, respectively, in the group receiving the dose of 0.1 mmol/kg. There were no statistically significant differences between the means of both groups. While the absolute lesion-liver CNR values were 18+/-15 precontrast, 22+/-18 in the arterial phase, 19+/-17 in the portal phase, 15+/-10 in the venous phase and 24+/-26 in the late phase in the group receiving the standard dose Gd-BOPTA, these values were 13+/-11, 18+/-15, 15+/-15, 13+/-13 and 19+/-21, respectively, in the group receiving the 0.1 mmol/kg dose. There were no statistically significant differences between the means of both groups (p>0.05). However, when the mean lesion-liver CNR values were compared, there was statistically significant difference between each arterial and portal phases of metastases in both groups (p<0.05). There was no statistical difference found in other lesions. When lesion conspicuity scores were compared, there were no significant differences between the two groups.
  
  
  CONCLUSIONS
  In liver lesions, similar diagnostic data are obtained in dynamic and late phase MRI with either standard dose Gd-BOPTA or with a dose of 0.1 mmol/kg. Because there was a difference in only metastases in both groups, in oncological patients who are being investigated for liver metastasis, it is expedient to use a dose of 0.1 mmol/kg.
authors.affiliation: Ondokuz Mayis University, Faculty of Medicine, Department of Radiology, Samsun, Turkey.
authors.forename: Mehmet Selim
authors.initials: MS
authors.lastname: Nural
authors.forename: Erkan
authors.initials: E
authors.lastname: Gokce
authors.forename: Murat
authors.initials: M
authors.lastname: Danaci
authors.forename: Ilkay Koray
authors.initials: IK
authors.lastname: Bayrak
authors.forename: H Baris
authors.initials: HB
authors.lastname: Diren
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003287:Contrast Media / Q000008:administration & dosage* / Q000493:pharmacokinetics; D005260:Female; D006801:Humans; D008107:Liver Diseases / Q000175:diagnosis*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008536:Meglumine / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000493:pharmacokinetics; D008875:Middle Aged; D009942:Organometallic Compounds / Q000008:administration & dosage* / Q000493:pharmacokinetics; D018709:Statistics, Nonparametric
chemical_list: D003287:Contrast Media; D009942:Organometallic Compounds; C064572:gadobenic acid; D008536:Meglumine