title: Superparamagnetic iron oxide (SPIO) enhancement in the cirrhotic liver: a comparison of two doses of ferumoxides in patients with advanced disease.
abstract: The aim of this study was to establish whether enhancement of the liver by the MRI contrast agent ferumoxides could be effectively achieved at a reduced dose of 7.5 micromol/kg in patients with advanced liver cirrhosis. Forty-two liver transplant candidates with end-stage cirrhosis underwent SPIO-enhanced MRI at 1.5T, using either 15 micromol/kg or 7.5 micromol/kg ferumoxides. The lower dose of ferumoxides was also used in 21 non-cirrhotic patients with colorectal liver metastases who acted as a control group. The percentage signal intensity loss (PSIL) after SPIO was measured in all patients, and in those patients with tumors the post-SPIO contrast-to-noise ratio (CNR) was measured. The median PSIL after SPIO in the high dose cirrhotic (HDLC), low dose non-cirrhotic (LDNC) and low dose cirrhotic (LDLC) patients was 86.3%, 74.6%, and 64.2% respectively. These differences were significant using the Mann-Whitney U test. Tumors were found in 8 patients in the high dose cirrhotic group, 9 in the low dose cirrhotic group, and all 21 of the control group. No significant differences were found between the CNR values after SPIO in the 3 groups (median values HDLC 15.1, LDNC 23.7, LDLC 19.5). In patients with late-stage cirrhosis the PSIL after SPIO was significantly less at 7.5 micromol/kg than at 15 micromol/kg, but both doses produced a substantial loss of signal. Lesion to liver CNR was not adversely affected by using the lower dose, so when imaging at 1.5T the authors would recommend using 7.5 micromol/kg in patients with liver cirrhosis.
authors.affiliation: Clinical Radiology, St. James's University Hospital, Beckett Street, Leeds, LS9 7TF, UK.
authors.forename: Paul
authors.initials: P
authors.lastname: Arnold
authors.forename: Janice
authors.initials: J
authors.lastname: Ward
authors.forename: Daniel
authors.initials: D
authors.lastname: Wilson
authors.forename: J
authors.initials: J
authors.lastname: Ashley Guthrie
authors.forename: Philip J
authors.initials: PJ
authors.lastname: Robinson
mesh_terms: D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D003287:Contrast Media / Q000008:administration & dosage*; D003911:Dextrans; D005260:Female; D052203:Ferrosoferric Oxide; D006801:Humans; D007501:Iron / Q000008:administration & dosage*; D008099:Liver / Q000473:pathology; D008103:Liver Cirrhosis / Q000473:pathology*; D008113:Liver Neoplasms / Q000473:pathology / Q000556:secondary; D016031:Liver Transplantation; D008279:Magnetic Resonance Imaging; D058185:Magnetite Nanoparticles; D008297:Male; D008875:Middle Aged; D010087:Oxides / Q000008:administration & dosage*; D013535:Suspensions
chemical_list: D003287:Contrast Media; D003911:Dextrans; D058185:Magnetite Nanoparticles; D010087:Oxides; D013535:Suspensions; D007501:Iron; C065507:ferumoxides; D052203:Ferrosoferric Oxide