Enhancement of computed tomography liver contrast using iomeprol-containing liposomes and detection of small liver tumors in rats.
OBJECTIVE
We evaluated iomeprol-containing liposomes (Lipiom), a new contrast medium for computed tomography (CT) liver scanning, in an animal model of chemically induced hepatocellular carcinomas and other liver tumors in rats.


METHODS
Liver tumors were induced by administration of carcinogens to rats, either 0.55% (w/w) 1'-hydroxysafrole in the diet or induction by 3'-methyl-4-diethylaminoazobenzene followed by promotion with carbon tetrachloride. CT scanning was performed 1-3 hr after intravenous injection of iomeprol-containing liposomes.


RESULTS
After injection of iomeprol-containing liposomes at a dose of 70 mg of liposome-entrapped iodine per kilogram of body weight, the normal liver parenchyma showed a contrast enhancement, in Hounsfield units, of more than 60% over the control value before bolus. Liver tumors with no or few Kupffer cells were not enhanced and appeared as dark areas within the normal parenchyma. Tumors and pretumoral lesions devoid of Kupffer cells, as small as 3 mm in diameter, could be distinguished using this non-invasive method.


CONCLUSIONS
CT liver scanning after injection of iomeprol-containing liposomes appears to be promising method for detecting liver tumors and focal liver lesions.
Fouillet
X
X
Bracco Research SA, Geneva, Switzerland.
Tournier
H
H
Khan
H
H
Sabitha
S
S
Burkhardt
S
S
Terrier
F
F
Schneider
M
M
D000818:Animals; D006528:Carcinoma, Hepatocellular / Q000000981:diagnostic imaging* / Q000473:pathology; D003287:Contrast Media; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D004337:Drug Carriers; D005260:Female; D007275:Injections, Intravenous; D007479:Iopamidol / Q000031:analogs & derivatives*; D007728:Kupffer Cells / Q000473:pathology; D008081:Liposomes; D008114:Liver Neoplasms, Experimental / Q000000981:diagnostic imaging* / Q000473:pathology; D008297:Male; D011856:Radiographic Image Enhancement / Q000379:methods*; D051381:Rats; D017207:Rats, Sprague-Dawley; D014057:Tomography, X-Ray Computed
D003287:Contrast Media; D004337:Drug Carriers; D008081:Liposomes; C057937:iomeprol; D007479:Iopamidol