Marco Rengo MD, Presenter: Nothing to Disclose

Damiano Caruso MD, Abstract Co-Author: Nothing to Disclose

Anoeshka Shashikala Dharampal MD, Abstract Co-Author: Nothing to Disclose

Alexia Rossi MD, Abstract Co-Author: Nothing to Disclose

Koen Nieman MD, Abstract Co-Author: Nothing to Disclose

Nico R. Mollet MD, Abstract Co-Author: Nothing to Disclose

Pim J. De Feyter MD, PhD, Abstract Co-Author: Nothing to Disclose

Andrea Laghi MD, Abstract Co-Author: Speaker, Bracco Group Research Consultant, General Electric Company

Gabriel P. Krestin MD, PhD, Abstract Co-Author: Consultant, General Electric Company Research Grant, General Electric Company Research Grant, Bayer AG Research Grant, Siemens AG

To explore the relative impacts of iodine concentration versus iodine delivery rate on intra-coronary attenuation. To describe the effect of iodine concentration on contrast bolus characteristics.

Two hundred Fifty patients were prospectively randomized in 4 groups and underwent CT Coronary Angiography (CTCA). Four CM with different iodine concentrations (300, 350, 370, 400 mgI/ml) were delivered at a fix iodine delivery rate (2.0 mgI/s). Intracoronary attenuation values were measured and grouped on a per-vessel and per-segment bases. Time-to-peak, and pressure curves during CM injection were evaluated and compared.

Injection fluxes were 6.7 ml/sec, 5.7 ml/sec, 5.4 ml/sec and 5 ml/sec for group A, B, C and D respectively. Group A [300] and C [370] provided significantly higher intravascular attenuation values compared to group B [350] and D [400] (P<0.05) in both per segment and per vessel analysis. Time-to-peak was significantly earlier in group A (15.3 sec) than in the other three groups. The injection peak pressure was significantly lower in group A (185.16 psi) and C (189.05 psi) than in group B (215.89 psi) and D (243.33 psi). No extravasations were noted in all groups.

Despite the four CM were injected at the same IDR intravascular attenuation values were not equal. The influence of chemico-physical characteristics influenced also the other injection parameters. In particular a non correspondence between the injection flux and the injection pressure was observed among groups.

Contrast media injection protocols should not be optimized according the iodine concentration only, but also to the chemico-physical characteristics of each compound.

Rengo, M, Caruso, D, Dharampal, A, Rossi, A, Nieman, K, Mollet, N, De Feyter, P, Laghi, A, Krestin, G, CT Coronary Angiography: Effect of Iodine Concentration on Vascular Attenuation–The CT-CON Multicentric Study Preliminary Results.  Radiological Society of North America 2012 Scientific Assembly and Annual Meeting, November 25 - November 30, 2012 ,Chicago IL. http://archive.rsna.org/2012/12037599.html