Effect of injection rate of contrast medium on pancreatic and hepatic helical CT.
OBJECTIVE
To assess the effect of the injection rate of contrast medium on pancreatic and hepatic enhancement at abdominal helical computed tomography (CT).


METHODS
Sixty-four contrast medium-enhanced abdominal helical CT scans (64 adult patients) were obtained with 150 mL of contrast medium. The injection rate was 2.5 mL/sec for the first 32 scans and 5.0 mL/sec for the remaining 32. Scans were obtained at 5-sec intervals, with an intermediate 8-sec breathing interval. Hepatic and pancreatic enhancement levels were measured and averaged, and time-attenuation curves were plotted for both groups. Differences in weight, age, time to peak pancreatic and hepatic enhancement, and peak enhancement were assessed with the Student t test.


RESULTS
Both peak enhancement and time to peak enhancement were significantly different between the two injection rates (P < or = .002), with faster, more intense hepatic and pancreatic enhancement at the higher rate. At 2.5 mL/sec, the pancreas reached a peak attenuation level of 65 HU at 69 sec, and the liver reached a peak of 58 HU at 87 sec. At 5.0 mL/sec, the pancreas reached a peak attenuation of 84 HU at 43 sec, and the liver reached a peak of 75 HU at 63 sec.
Tublin
M E
ME
Department of Radiology, Albany Medical Center, Albany, NY 12208, USA.
Tessler
F N
FN
Cheng
S L
SL
Peters
T L
TL
McGovern
P C
PC
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003287:Contrast Media / Q000008:administration & dosage*; D003974:Diatrizoate Meglumine / Q000008:administration & dosage; D005260:Female; D006801:Humans; D007275:Injections, Intravenous / Q000379:methods; D007472:Iohexol / Q000008:administration & dosage; D008099:Liver / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D010179:Pancreas / Q000000981:diagnostic imaging*; D011446:Prospective Studies; D014057:Tomography, X-Ray Computed
D003287:Contrast Media; D003974:Diatrizoate Meglumine; D007472:Iohexol