Low- versus high-osmolality contrast media.
OBJECTIVE
To evaluate the effects of contrast media pharmokinetic differences on aortic enhancement at abdominal CT angiography and to determine whether these effects are of clinical relevance.


METHODS
Two hundred and twelve patients referred for abdominal CT angiography were included in the study. All abdominal CT angiograms were performed with the same parameters (collimation 3 mm, pitch ratio 1.7, scan delay 30 s) after i.v. injection of 120 ml of contrast medium at 3 ml/s. After randomization, patients received either iobitridol 300 (low-osmolar, 300 mg I/ml), iobitridol 350 (low-osmolar, 350 mg I/ml) or ioxithalamate 350 (high-osmolar, 350 mg I/ml). The time attenuation curves obtained with the three contrast media were compared.


RESULTS
The time attenuation curve obtained with ioxithalamate 350 was not parallel to those obtained with iobitridol 300 and iobitridol 350. Mean peak enhancements obtained with iobitridol 350 and ioxithalamate 350 were not significantly different but iobitridol 350 provided higher mean peak enhancement than iobitridol 300. Mean delays of the peak enhancements were the same with the three contrast media. After peak enhancement, the decrease of aortic opacification under a selected threshold of 200 HU was significantly slower with iobitridol 350 than with iobitridol 300 and ioxithalamate 350, whereas iobitridol 300 and ioxithalamate 350 showed no significant differences.


CONCLUSIONS
For a given iodine concentration, low-osmolality contrast media provide longer aortic opacification and may be recommended for CT angiography when long acquisition times are needed.
Rouvière
O
O
Department of Vascular and Genitourinary Radiology, Hôital E. Herriot, Lyon, France.
Ecochard
R
R
Berger
P
P
Pangaud
C
C
Fontaine
B
B
Lyonnet
D
D
D000328:Adult; D001011:Aorta / Q000473:pathology*; D001018:Aortic Diseases / Q000000981:diagnostic imaging; D001027:Aortography; D003287:Contrast Media / Q000008:administration & dosage / Q000737:chemistry* / Q000493:pharmacokinetics; D005260:Female; D006801:Humans; D007083:Iliac Artery / Q000000981:diagnostic imaging; D007275:Injections, Intravenous; D007455:Iodine / Q000008:administration & dosage / Q000737:chemistry / Q000493:pharmacokinetics; D007472:Iohexol / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000737:chemistry / Q000493:pharmacokinetics; D007483:Iothalamic Acid / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000737:chemistry / Q000493:pharmacokinetics; D007674:Kidney Diseases / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D009994:Osmolar Concentration; D016491:Peripheral Vascular Diseases / Q000000981:diagnostic imaging; D011856:Radiographic Image Enhancement; D011860:Radiography, Abdominal; D013997:Time Factors; D014057:Tomography, X-Ray Computed
D003287:Contrast Media; D007483:Iothalamic Acid; C093233:iobitridol; D007472:Iohexol; D007455:Iodine; C002587:ioxitalamic acid