Contrast Enhancement in Chest Multidetector Computed Tomography: Intraindividual Comparison of 300 mg/ml versus 400 mg/ml Iodinated Contrast Medium

Abstract

We sought to intraindividually compare intravascular contrast enhancement in multidector computed tomography (MDCT) of the chest using contrast media (CM) containing 300 and 400 mg iodine/ml. Seventy-one patients underwent repeated MDCT scanning of the chest at baseline and follow-up. CM with standard iodine (protocol A: 300 mg iodine/ml; Iopromide 300) and high iodine concentration (protocol B: 400 mg iodine/ml; Iomeprol 400) were used. The iodine delivery rate (1.29 g iodine/s) and total iodine load (37 g iodine) were identical for the two protocols. Contrast enhancement was measured in the right and left ventricles, pulmonary trunk, right and left pulmonary arteries, and ascending and descending aortas. Results were compared using paired t-tests; P values were adjusted using Bonferroni correction (P <or= .005). Contrast enhancement values showed no statistically significant differences between the two protocols at all anatomic sites (all P > .005). In the right ventricle, pulmonary trunk, and right and left pulmonary arteries, higher attenuation values for protocol A were detected compared to protocol B (379.0 +/- 110.5 vs. 349.8 +/- 117.6, 354.5 +/- 112.2 vs 330.9 +/- 118.3, 348.6 +/- 106.0 vs. 321.8 +/- 109.9, and 347.9 +/- 102.4 vs. 321.0 +/- 104.9 HU, respectively). After the lung circulation (left ventricle, ascending aorta, and descending aorta), attenuation values were marginally higher for protocol B. Using both protocols resulted in suitable contrast enhancement with a mean pulmonary attenuation higher than 300 HU. Using an adapted injection protocol, the administration of 300 and 400 mg iodine CM resulted in a suitable intravascular contrast enhancement in the chest. The use of 400 mg iodine CM does not lead to a statistically significant improvement in contrast enhancement compared to the 300 mg iodine CM.