title: A prospective study comparing different iodine concentrations for triphasic multidetector row CT of the upper abdomen.
abstract: OBJECTIVE
  To investigate the effect of different iodine concentrations at either constant injection or iodine administration rates but constant total iodine load on contrast enhancement of liver, pancreas and spleen by multidetector row CT.
  
  
  METHODS
  One hundred and twenty consecutive patients (70+/-6 years) underwent triphasic liver CT at a four-channel multidetector-row CT using the non-ionic contrast medium iopromide. Patients were divided into six equal groups-I: 150 ml, 240 mg/ml at 4 ml/s; II: 120 ml, 300 mg/ml at 4 ml/s; III: 97.3 ml, 370 mg/ml at 4 ml/s; IV: 150 ml, 240 mg/ml at 5 ml/s; V: 120 ml, 300 mg/ml, 60 ml at 6 ml/s, 60 ml at 3 ml/s; VI: 97.3 ml, 370 mg/ml at 3.3 ml/s. ROIs were measured in the liver, the pancreas, and the spleen in unenhanced, arterial, portal venous, and equilibrium phase.
  
  
  RESULTS
  At a constant injection rate of 4 ml/s, pancreatic enhancement over baseline only in the arterial phase was significantly higher at 370 mg/ml (58+/-15 HU versus 59+/-18 HU versus 74+/-20 HU for groups I-III, respectively (p<0.02)). Comparison of different iodine concentrations at constant iodine administration rate (groups II, IV and VI) and of all six protocols revealed no significant differences at either phase.
  
  
  CONCLUSIONS
  At a constant iodine load and constant injection rates, the high-iodinated contrast agent iopromide at 370 mg/ml improves pancreatic enhancement in the arterial phase. At constant iodine load and constant iodine administration rates, there is no significant effect of different iodine concentrations.
authors.affiliation: Department of Radiology, University of Wuerzburg, Josef-Schneider-Strasse 2, Wuerzburg, Germany. sandstede@web.de
authors.forename: Joern J W
authors.initials: JJ
authors.lastname: Sandstede
authors.forename: Alexander
authors.initials: A
authors.lastname: Werner
authors.forename: Christine
authors.initials: C
authors.lastname: Kaupert
authors.forename: Anne
authors.initials: A
authors.lastname: Roth
authors.forename: Manfred
authors.initials: M
authors.lastname: Jenett
authors.forename: Cornelia
authors.initials: C
authors.lastname: Harz
authors.forename: Dietbert
authors.initials: D
authors.lastname: Hahn
mesh_terms: D000368:Aged; D003287:Contrast Media; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D007472:Iohexol / Q000008:administration & dosage / Q000031:analogs & derivatives*; D008297:Male; D011446:Prospective Studies; D011856:Radiographic Image Enhancement / Q000379:methods*; D011860:Radiography, Abdominal / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000295:instrumentation* / Q000379:methods*
chemical_list: D003287:Contrast Media; D007472:Iohexol; C038192:iopromide