Computed tomography of experimental liver metastases using an iodinated hepatocyte-specific lipid emulsion. A correlative study in the nude rat.
OBJECTIVE
A hepatocyte-specific iodinated lipid emulsion, NRI 757, was used for detection of experimental hepatic metastases.


METHODS
The study was performed in a correlative model of multiple hepatic metastases from a human colonic cancer implanted in the nude rat.


RESULTS
After intravenous injection, normal liver parenchyma remained enhanced for several hours, whereas the uptake in hepatic metastases was negligible. A liver-to-lesion contrast of 45 Hounsfield units (HU) was obtained at a dose of 1 mL NRI 757/kg body weight (BW). In a lesion-by-lesion analysis of 177 metastases ranging in size from 1 to 32 mm, the mean +/- standard deviation overall detection rate for native scanning and contrast-enhanced scanning in vivo and post mortem, 20 +/- 0.4%, 53 +/- 5.2%, and 55 +/- 4.0%, respectively and 28%, 84%, and 82%, retrospectively. When metastatic size also was considered, for native scanning the maximum detection rate of 61% was reached for 8- to 10-mm lesions, whereas for contrast-enhanced computed tomography scanning, 100% of the 5- to 7-mm lesions and 42% of the 1- to 2-mm nodules were detected.


CONCLUSIONS
The use of NRI 757 improved the diagnostic yield considerably.
Sundin
A
A
Department of Diagnostic Radiology, Uppsala University, Akademiska Sjukhuset, Sweden.
Ahlström
H
H
Graf
W
W
Magnusson
A
A
D000230:Adenocarcinoma / Q000000981:diagnostic imaging* / Q000473:pathology / Q000556:secondary*; D000818:Animals; D002784:Cholesterol / Q000008:administration & dosage; D003110:Colonic Neoplasms; D003287:Contrast Media / Q000008:administration & dosage; D004655:Emulsions; D005217:Fat Emulsions, Intravenous / Q000008:administration & dosage; D005260:Female; D006801:Humans; D007275:Injections, Intravenous; D007459:Iodized Oil / Q000008:administration & dosage; D008099:Liver / Q000166:cytology / Q000000981:diagnostic imaging; D008113:Liver Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology / Q000556:secondary*; D008297:Male; D009368:Neoplasm Transplantation; D010743:Phospholipids; D011856:Radiographic Image Enhancement / Q000379:methods; D051381:Rats; D011923:Rats, Nude; D013997:Time Factors; D014057:Tomography, X-Ray Computed / Q000379:methods; D014407:Tumor Cells, Cultured
D003287:Contrast Media; D004655:Emulsions; D005217:Fat Emulsions, Intravenous; D010743:Phospholipids; C092563:iodized oil, phospholipid, cholesterol emulsion; D007459:Iodized Oil; D002784:Cholesterol