title: Effect of injection rate of contrast medium on pancreatic and hepatic helical CT.
abstract: 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.
authors.affiliation: Department of Radiology, Albany Medical Center, Albany, NY 12208, USA.
authors.forename: M E
authors.initials: ME
authors.lastname: Tublin
authors.forename: F N
authors.initials: FN
authors.lastname: Tessler
authors.forename: S L
authors.initials: SL
authors.lastname: Cheng
authors.forename: T L
authors.initials: TL
authors.lastname: Peters
authors.forename: P C
authors.initials: PC
authors.lastname: McGovern
mesh_terms: 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
chemical_list: D003287:Contrast Media; D003974:Diatrizoate Meglumine; D007472:Iohexol