Detection of liver metastases: comparison of gadobenate dimeglumine-enhanced and ferumoxides-enhanced MR imaging examinations.
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.
del Frate
Chiara
C
Institute of Radiology, Udine University, Policlinico Universitario a Gestione diretta, via Colugna 50, 33100 Udine, Italy. iaiacdf@hotmail.com
Bazzocchi
Massimo
M
Mortele
Koenraad J
KJ
Zuiani
Chiara
C
Londero
Viviana
V
Como
Giuseppe
G
Zanardi
Romeo
R
Ros
Pablo R
PR
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
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