title: Contrast bolus optimization for cardiac 16-slice computed tomography: comparison of contrast medium formulations containing 300 and 400 milligrams of iodine per milliliter.
abstract: OBJECTIVE
  The aims of our study were to compare contrast injection protocols with contrast media containing 300 and 400 mg iodine per milliliter for optimal contrast enhancement in cardiac multidector row computed tomography (CT) and to evaluate the correlation of test bolus curve parameters with the final contrast density of the main bolus.
  
  
  METHODS
  Sixty patients with known or suspected coronary artery disease were included in a prospective double-blind study. Patients were randomized to 2 groups. Group 1 received 83 mL of a contrast medium (CM) containing 300 mg of iodine (Iomeron 300, Bracco Imaging SpA, Milan, Italy) at a flow rate of 3.3 mL/s, whereas group 2 received 63 mL of the same agent containing 400 mg of iodine (Iomeron 400) at a flow rate of 2.5 mL/s. The test bolus volumes were 20 mL and 15 mL, respectively. Imaging was performed using a 16-slice CT system (16DCT; Somatom Sensation 16, Siemens Medical Solutions, Forchheim, Germany). Contrast densities (Hounsfield Units [HU]) were determined in the cardiac chambers and in the main coronary arteries. The peak density and area under the curve of the test bolus were calculated for each patient.
  
  
  RESULTS
  The mean contrast densities of the coronary arteries were 259.1 +/- 46.7 HU for group 1 and 251.6 +/- 51.0 HU, for group 2. No noteworthy differences between groups were noted for density measurements in the cardiac chambers or for the ratio of right-to-left ventricle density. Whereas a positive correlation was noted for both groups between the area under the curve of the test bolus and the mean density of the main bolus, a positive correlation between peak density of the test bolus and mean density of the main bolus was noted only for group 1.
  
  
  CONCLUSIONS
  Equivalent homogenous enhancement of the ventricular cavities and coronary arteries to that obtained using a CM with standard iodine concentration (Iomeron 300) can be achieved with lower overall volumes of administered CM and reduced injection flow rates when a CM with high iodine concentration (Iomeron 400) is used.
authors.affiliation: Department of Clinical Radiology, University Hospitals--Grosshadern, Ludwig-Maximilians University, Munich, Germany. carsten.rist@med.uni-muenchen.de
authors.forename: Carsten
authors.initials: C
authors.lastname: Rist
authors.forename: Konstantin
authors.initials: K
authors.lastname: Nikolaou
authors.forename: Miles A
authors.initials: MA
authors.lastname: Kirchin
authors.forename: Roland
authors.initials: R
authors.lastname: van Gessel
authors.forename: Kyongtae Ty
authors.initials: KT
authors.lastname: Bae
authors.forename: Franz
authors.initials: F
authors.lastname: von Ziegler
authors.forename: Andreas
authors.initials: A
authors.lastname: Knez
authors.forename: Bernd J
authors.initials: BJ
authors.lastname: Wintersperger
authors.forename: Maximilian F
authors.initials: MF
authors.lastname: Reiser
authors.forename: Christoph R
authors.initials: CR
authors.lastname: Becker
mesh_terms: D000328:Adult; D003287:Contrast Media / Q000008:administration & dosage* / Q000009:adverse effects; D017023:Coronary Angiography / Q000379:methods*; D003327:Coronary Disease / Q000000981:diagnostic imaging*; D003331:Coronary Vessels / Q000473:pathology*; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007275:Injections, Intravenous; D007479:Iopamidol / Q000008:administration & dosage / Q000009:adverse effects / Q000031:analogs & derivatives*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D003287:Contrast Media; C057937:iomeprol; D007479:Iopamidol