Detection of focal liver lesions at biphasic spiral CT: randomized double-blind study of the effect of iodine concentration in contrast materials.
OBJECTIVE
To evaluate the effect of iodine concentration on the detection of focal liver lesions at biphasic spiral computed tomography (CT).


METHODS
One hundred two patients (64 men, 38 women) with neoplastic (n = 85) and nonneoplastic focal lesions (n = 17) were prospectively assigned to biphasic injection group A or B and received 180 mL of iopromide containing 370 or 300 mg of iodine per milliliter, respectively, during spiral CT. Comparison included assessment of quantitative and qualitative parameters.


RESULTS
Hepatic time-attenuation curves and mean hepatic enhancement in the portal venous phase and aortic time-attenuation curves in both arterial and portal venous phases were statistically superior in group A compared with group B. There was no significant difference in the mean enhancement in all lesions in either group. In contrast, among patients with hepatocellular carcinoma, mean contrast enhancement in lesions in the arterial phase was significantly superior in group A compared with group B. Blinded readers classified hepatic attenuation and lesion visibility as very good and as improved significantly more often in group A than in group B.


CONCLUSIONS
A decrease in iodine concentration significantly affects aortic and hepatic contrast enhancement and may impair the detectability of focal liver lesions during biphasic spiral CT.
Department of Radiology, Charité Medical University Center, Campus Virchow Clinic, Humboldt University, D-13344 Berlin, Germany. elh@charite.de
E L
EL
Hänninen
T J
TJ
Vogl
R
R
Felfe
W
W
Pegios
J
J
Balzer
W
W
Clauss
R
R
Felix
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001011:Aorta; D006528:Carcinoma, Hepatocellular / Q000000981:diagnostic imaging; D003287:Contrast Media / Q000008:administration & dosage; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D007275:Injections, Intravenous; D007455:Iodine / Q000008:administration & dosage; D007472:Iohexol / Q000008:administration & dosage / Q000031:analogs & derivatives*; D008099:Liver / Q000000981:diagnostic imaging; D008107:Liver Diseases / Q000000981:diagnostic imaging*; D008113:Liver Neoplasms / Q000000981:diagnostic imaging* / Q000556:secondary; D008297:Male; D008875:Middle Aged; D011169:Portal Vein; D011446:Prospective Studies; D011856:Radiographic Image Enhancement / Q000379:methods; D013997:Time Factors; D014057:Tomography, X-Ray Computed / Q000379:methods*
D003287:Contrast Media; D007472:Iohexol; C038192:iopromide; D007455:Iodine