title: Detection of liver metastases: comparison of gadobenate dimeglumine-enhanced and ferumoxides-enhanced MR imaging examinations.
abstract: OBJECTIVE
  To compare gadobenate dimeglumine (Gd-BOPTA)-enhanced magnetic resonance (MR) imaging with ferumoxides-enhanced MR imaging for detection of liver metastases.
  
  
  METHODS
  Twenty consecutive patients known to have malignancy and suspected of having focal liver lesions at ultrasonography (US) underwent 1.0-T MR imaging with gradient-recalled-echo T1-weighted breath-hold sequences before, immediately after, and 60 minutes after Gd-BOPTA injection. Subsequently, MR imaging was performed with turbo spin-echo short inversion time inversion-recovery T2-weighted sequences before and 60 minutes after ferumoxides administration. All patients subsequently underwent intraoperative US within 15 days, and histopathologic analysis of their resected lesion-containing specimens was performed. Separate qualitative analyses were performed to assess lesion detection with each contrast agent. Quantitative analyses were performed by measuring signal-to-noise and contrast-to-noise ratios (CNRs) on pre- and postcontrast Gd-BOPTA and ferumoxides MR images. Statistical analyses were performed with Wilcoxon signed rank and Monte Carlo tests.
  
  
  RESULTS
  Sensitivity of ferumoxides-enhanced MR imaging was superior to that of Gd-BOPTA-enhanced MR imaging for liver metastasis detection (P <.05). Ferumoxides MR images depicted 36 (97%) of 37 metastases detected at intraoperative US, whereas Gd-BOPTA MR images depicted 30 (81%) metastases during delayed phase and 20 (54%) during dynamic phase. All six metastases identified only at ferumoxides-enhanced MR imaging were 5-10 mm in diameter. There was a significant increase in CNR between the lesion and liver before and after ferumoxides administration (from 3.8 to 6.8, P <.001) but not before or after Gd-BOPTA injection (from -4.8 to -5.5, P >.05).
  
  
  CONCLUSIONS
  Ferumoxides-enhanced MR imaging seems to be superior to Gd-BOPTA-enhanced MR imaging for liver metastasis detection.
authors.affiliation: Institute of Radiology, Udine University, Policlinico Universitario a Gestione diretta, via Colugna 50, 33100 Udine, Italy. iaiacdf@hotmail.com
authors.forename: Chiara
authors.initials: C
authors.lastname: del Frate
authors.forename: Massimo
authors.initials: M
authors.lastname: Bazzocchi
authors.forename: Koenraad J
authors.initials: KJ
authors.lastname: Mortele
authors.forename: Chiara
authors.initials: C
authors.lastname: Zuiani
authors.forename: Viviana
authors.initials: V
authors.lastname: Londero
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Como
authors.forename: Romeo
authors.initials: R
authors.lastname: Zanardi
authors.forename: Pablo R
authors.initials: PR
authors.lastname: Ros
mesh_terms: D015179:Colorectal Neoplasms / Q000473:pathology; D003287:Contrast Media; D003911:Dextrans; D005260:Female; D052203:Ferrosoferric Oxide; D005682:Gadolinium; D006801:Humans; D007501:Iron; D008113:Liver Neoplasms / Q000175:diagnosis* / Q000556:secondary*; D008279:Magnetic Resonance Imaging; D058185:Magnetite Nanoparticles; D008297:Male; D008536:Meglumine / Q000031:analogs & derivatives*; D008875:Middle Aged; D009942:Organometallic Compounds; D010087:Oxides; D013535:Suspensions
chemical_list: D003287:Contrast Media; D003911:Dextrans; D058185:Magnetite Nanoparticles; D009942:Organometallic Compounds; D010087:Oxides; D013535:Suspensions; C064572:gadobenic acid; D008536:Meglumine; D005682:Gadolinium; D007501:Iron; C065507:ferumoxides; D052203:Ferrosoferric Oxide