Influence of osmolarity of contrast medium and saline flush on computed tomography angiography: comparison of monomeric and dimeric iodinated contrast media with different iodine concentrations at an identical iodine delivery rate.
OBJECTIVE
To evaluate the influence of osmolarity of iodinated contrast media and saline flush on the contrast effect in thoracic computed tomography angiography (CTA) at an identical iodine delivery rate (IDR).


METHODS
Seven beagles were used in a cross-over experiment. The contrast media used were iohexol 350 mgI/ml (IOH350; osmolarity 844 mmol/kg) and iodixanol 320 mgI/ml (IDX320; osmolarity 290 mmol/kg). Each contrast medium was administered to groups with and without saline flush at 40.0 mgI/kg/s for all experiments. Dynamic CT scanning was performed at the ninth thoracic vertebra level. The peak value, area under the curve (AUC), and time to peak (TTP) were calculated from the time attenuation curves of the pulmonary artery and aorta.


RESULTS
There was no significant difference between IOH350 and IDX320 with or without saline flush in the peak values for the pulmonary artery and aorta. AUC was significantly higher in groups with saline flush for both contrast media and arteries (p<0.05) with no significant difference between contrast media. TTP was significantly longer in groups with saline flush than without saline flush for both contrast media and arteries (p<0.05), with no significant difference between contrast media.


CONCLUSIONS
There were no significant differences in the contrast effects of monomeric IOH350 and dimeric IDX320 in thoracic CTA when used at an identical IDR. Moreover, saline flush prolonged the peak duration at 600 mgI/kg.
Kishimoto
Miori
M
Department of Clinical Veterinary Science, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Japan. miori@mx6.et.tiki.ne.jp
Doi
Shoko
S
Shimizu
Junichiro
J
Lee
Ki-Ja
KJ
Iwasaki
Toshiroh
T
Miyake
Yoh-Ichi
Y
Yamada
Kazutaka
K
D000792:Angiography; D000818:Animals; D001011:Aorta; D019540:Area Under Curve; D003287:Contrast Media / Q000737:chemistry*; D018592:Cross-Over Studies; D004285:Dogs; D007472:Iohexol / Q000737:chemistry*; D009994:Osmolar Concentration; D011651:Pulmonary Artery; D013902:Radiography, Thoracic; D012965:Sodium Chloride / Q000008:administration & dosage; D018709:Statistics, Nonparametric; D014057:Tomography, X-Ray Computed; D014283:Triiodobenzoic Acids / Q000737:chemistry*
D003287:Contrast Media; D014283:Triiodobenzoic Acids; D007472:Iohexol; D012965:Sodium Chloride; C044834:iodixanol