Contrast material injection for hepatic helical computed tomography. Comparative study of five protocols.
OBJECTIVE
The authors develop and compare contrast material injection protocols suitable for hepatic helical computed tomography.


METHODS
One hundred twenty-one patients who underwent contrast-enhanced computed tomography (CT) of the liver with spiral CT imaging were evaluated for enhancement of the liver parenchyma and for post-enhancement attenuation of the aorta and portal vein with iohexol. Patients were assigned randomly to five protocols with different flow rates, volume of contrast material, and scan delays.


RESULTS
Mean parenchymal contrast enhancement was statistically significantly higher with protocol 5 (biphasic injection of 100 mL of iohexol 300 (g/100 mL) at a flow rate of 1.5 mL/second followed by 25 mL at 2 mL/second; total iodine load = 37.5 g, with a scan delay of 70 seconds). The highest aortic enhancement and the second highest portal vein enhancement were obtained with this protocol.


CONCLUSIONS
The authors suggest an easily tolerated injection protocol able to ensure high parenchymal liver enhancement and satisfactory aortic and portal vein enhancement. This protocol includes a long scan delay (70 seconds), biphasic low flow injection rate, and a relatively low iodine load.
Hoeffel
C
C
Department of Radiology, Cochin Hospital, Paris, France.
Legmann
P
P
Girardot
C
C
Bunouf
P
P
Mezzi
K
K
Bonnin
A
A
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001011:Aorta; D001027:Aortography; D003287:Contrast Media / Q000008:administration & dosage*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007275:Injections, Intravenous; D007455:Iodine / Q000008:administration & dosage; D007472:Iohexol / Q000008:administration & dosage; D008099:Liver / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D011169:Portal Vein / Q000000981:diagnostic imaging; D011856:Radiographic Image Enhancement / Q000379:methods; D014057:Tomography, X-Ray Computed / Q000379:methods*
D003287:Contrast Media; D007472:Iohexol; D007455:Iodine