title: Comparison of half-dose and full-dose gadolinium MR contrast on the enhancement of bone and soft tissue tumors.
abstract: OBJECTIVE
  To evaluate the effect of half-dose intravenous gadolinium contrast on the enhancement of bone and soft tissue tumors.
  
  
  METHODS
  This study is HIPAA compliant and informed consent was waived by the institutional review board. An institutional database search was performed over a 1-year period for patients with full- and half-dose MR examinations performed for musculoskeletal oncologic indications. Examination pairs that were identical with regard to field strength and presence or absence of fat saturation were included, resulting in 29 paired examinations. When multiple, the lesion that was best delineated and enhanced well on the first examination in the pair was chosen, yielding 17 bone and 12 soft tissue. Five musculoskeletal radiologists blinded to dosages were asked to assess for a difference in enhancement when comparing the lesion on both examinations and to rate the degree of difference on a three-point scale. They were also asked to identify the examination on which the lesion enhanced less (tallied as low dose). Results were analyzed with the exact binomial test.
  
  
  RESULTS
  The readers perceived an enhancement difference in 41% (59/145) of studies (p = 0.03) and the majority were rated as "mild" (66%, 39/59). The readers did not accurately identify the low-dose examinations (54% correctly identified, 32/59, p = 0.60).
  
  
  CONCLUSIONS
  Half-dose gadolinium enhancement of lesions could not be accurately distinguished from full-dose enhancement upon review of the same lesion imaged at both concentrations.
authors.affiliation: Department of Diagnostic Radiology, University of Texas M. D. Anderson Cancer Center, Houston, Texas, USA. ccostelloe@di.mdacc.tmc.edu
authors.forename: Colleen M
authors.initials: CM
authors.lastname: Costelloe
authors.forename: William A
authors.initials: WA
authors.lastname: Murphy
authors.forename: Tamara M
authors.initials: TM
authors.lastname: Haygood
authors.forename: Rajendra
authors.initials: R
authors.lastname: Kumar
authors.forename: Kevin W
authors.initials: KW
authors.lastname: McEnery
authors.forename: R Jason
authors.initials: RJ
authors.lastname: Stafford
authors.forename: Anjali
authors.initials: A
authors.lastname: Roy
authors.forename: Roland L
authors.initials: RL
authors.lastname: Bassett
authors.forename: Robyn K
authors.initials: RK
authors.lastname: Harrell
authors.forename: John E
authors.initials: JE
authors.lastname: Madewell
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001859:Bone Neoplasms / Q000473:pathology*; D003287:Contrast Media / Q000008:administration & dosage; D004305:Dose-Response Relationship, Drug; D005260:Female; D005682:Gadolinium / Q000008:administration & dosage*; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012983:Soft Tissue Neoplasms / Q000473:pathology*
chemical_list: D003287:Contrast Media; D005682:Gadolinium