title: Enhancement in a brain glioma model: a comparison of half-dose gadobenate dimeglumine versus full-dose gadopentetate dimeglumine at 1.5 and 3 T.
abstract: OBJECTIVE
  To examine dose reduction comparing enhancement with full-dose gadopentetate dimeglumine (0.1 mmol/kg) to half-dose gadobenate dimeglumine in a rat brain glioma model.
  
  
  METHODS
  Intra-axial parenchymal brain tumors were implanted in 17 experimental animals. The 13 surviving animals were imaged at 1.5 or 3 T. Either gadopentetate dimeglumine or gadobenate dimeglumine was injected in random order on consecutive days. Tumor signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and contrast enhancement (CE) for each agent were obtained with region of interest analyses and compared. Lesions were confirmed histopathologically.
  
  
  RESULTS
  Statistically significantly lower SNR, CNR, and CE parameters were found at both 1.5 and 3 T with half-dose gadobenate dimeglumine relative to full-dose gadopentetate dimeglumine (P < 0.05). SNR on average at 3 T was 70.0 ± 14.4 for gadopentetate dimeglumine and 57.0 0 ± 4.8 for gadobenate dimeglumine (P < 0.02).
  
  
  CONCLUSIONS
  Improved r1 relaxivity with gadobenate dimeglumine does not produce adequate half-dose contrast-enhancement relative to full-dose gadopentetate dimeglumine.
authors.affiliation: Department of Radiology, Scott & White Clinic and Hospital, Texas A&M University Health Science Center. Temple, Texas, USA. Dr.john.morelli@gmail.com
authors.forename: John N
authors.initials: JN
authors.lastname: Morelli
authors.forename: Clint M
authors.initials: CM
authors.lastname: Gerdes
authors.forename: Wei
authors.initials: W
authors.lastname: Zhang
authors.forename: Jonathon M
authors.initials: JM
authors.lastname: Williams
authors.forename: Megan R
authors.initials: MR
authors.lastname: Saettele
authors.forename: Fei
authors.initials: F
authors.lastname: Ai
mesh_terms: D000818:Animals; D001932:Brain Neoplasms / Q000473:pathology*; D003287:Contrast Media / Q000008:administration & dosage; D004305:Dose-Response Relationship, Drug; D019786:Gadolinium DTPA / Q000008:administration & dosage*; D005910:Glioma / Q000473:pathology*; D007089:Image Enhancement / Q000379:methods*; D051381:Rats; D011916:Rats, Inbred F344; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA
keywords: 3 T; MRI; dose reduction; gadobenate dimeglumine