Magnetic resonance imaging of focal liver lesions. Comparison of the superparamagnetic iron oxide resovist versus gadolinium-DTPA in the same patient.
OBJECTIVE
The authors assess the efficacy of static and dynamic magnetic resonance (MR) imaging using the superparamagnetic iron oxide SHU-555A (Resovist) versus standard dose of gadolinium (Gd)-DTPA in patients with focal liver lesions.


METHODS
Magnetic resonance imaging was performed in 30 patients suffering from histopathologically verified malignant (n = 22) and benign (n = 8) liver lesions. T2-weighted conventional and fat-suppressed as well as T1-weighted sequences were used before, during, and after fast intravenous administration of Resovist (1 mL/minute) at three doses of 4, 8, and 16 mumol/kg body weight. One week before the Resovist-enhanced MR imaging study 20 patients underwent Gd-DTPA-enhanced MR imaging.


RESULTS
Detection rate was improved for metastatic lesions revealing 36 lesions unenhanced versus 53 focal lesions using Resovist-enhanced MR imaging. Gadolinium-DTPA-enhanced scans showed no additional lesion versus unenhanced and Resovist-enhanced MR imaging. Static and dynamic imaging demonstrated no measurable percentage signal intensity loss (PSIL) using Resovist-enhanced MR imaging versus a percentage enhancement of 79.7% in Gd-DTPA enhanced scans. In the dynamic T2-weighted sequences, hepatocellular carcinoma nodules (n = 4) showed a rapid decrease in signal intensity starting at 44 seconds. Postinfusion of Resovist followed by a low, constant increase in signal intensity. Gadolinium-DTPA enhanced scans showed a percentage enhancement of 73.4 focal nodular hyperplasia (FNH) and hemangioma revealed a strong and early dose-dependent PSIL 44 to 60 seconds postinfusion with a prolonged signal loss for the FNH in the late study. Statistical evaluation revealed a statistically significant superiority of Resovist-enhanced MR imaging concerning the detection and delineation of focal liver lesions compared with unenhanced and Gd-DTPA enhanced scans (P < 0.05).


CONCLUSIONS
The fast infusion of the new superparamagnetic contrast agent Resovist shows advantages for dynamic and static MR imaging of focal liver lesions.
Department of Radiology, Humboldt University of Berlin, Rudolf Virchow Hospital, Germany.
T J
TJ
Vogl
R
R
Hammerstingl
W
W
Schwarz
S
S
Kümmel
P K
PK
Müller
T
T
Balzer
M J
MJ
Lauten
J O
JO
Balzer
M G
MG
Mack
C
C
Schimpfky
H
H
Schrem
W O
WO
Bechstein
P
P
Neuhaus
R
R
Felix
D006528:Carcinoma, Hepatocellular / Q000175:diagnosis; D003287:Contrast Media; D003911:Dextrans; D052203:Ferrosoferric Oxide; D005500:Follow-Up Studies; D005682:Gadolinium; D019786:Gadolinium DTPA; D006391:Hemangioma / Q000175:diagnosis; D006801:Humans; D007501:Iron; D008107:Liver Diseases / Q000175:diagnosis*; D008113:Liver Neoplasms / Q000175:diagnosis*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D058185:Magnetite Nanoparticles; D009942:Organometallic Compounds; D010087:Oxides; D004369:Pentetic Acid / Q000031:analogs & derivatives*; D011446:Prospective Studies; D013535:Suspensions
D003287:Contrast Media; D003911:Dextrans; D058185:Magnetite Nanoparticles; D009942:Organometallic Compounds; D010087:Oxides; D013535:Suspensions; D004369:Pentetic Acid; D005682:Gadolinium; D007501:Iron; C065507:ferumoxides; D019786:Gadolinium DTPA; D052203:Ferrosoferric Oxide