Eva Maria Fallenberg MD, Presenter: Research grant, Bayer AG Research grant, Siemens AG Research grant, General Electric Company Speaker, Siemens AG Speaker, General Electric Company Speaker, Bayer AG Travel support, Bayer AG

Tahir Durmus MD, Abstract Co-Author: Nothing to Disclose

Felix Diekmann MD, Abstract Co-Author: Research Grant, Bayer AG Research Grant, Koninklijke Philips Electronics NV

Diane Miriam Renz MD, Abstract Co-Author: Nothing to Disclose

Florian Engelken MD, MBChB, Abstract Co-Author: Nothing to Disclose

Angela Reles MD, Abstract Co-Author: Nothing to Disclose

Ulrich Bick MD, Abstract Co-Author: Travel support, General Electric Company Travel support, Carestream Health, Inc Speaker, General Electric Company Speaker, Carestream Health, Inc Equipment support, Hologic, Inc Equipment support, MeVis BreastCare GmbH & Co KG Equipment support, Toshiba Corporation License agreement, Hologic, Inc Royalties, Hologic, Inc

Matthias Taupitz MD, PhD, Abstract Co-Author: Nothing to Disclose

There is evidence that macrocyclic MR contrast agents have negligible propensity to release gadolinium in contrast to linear MR contrast media. Therefore, they are recommended by the FDA and EMA to reduce side effects, e.g. NSF, esp. in renally impaired patients. Most dynamic breast MRI studies are performed using linear contrast agents. Our aim was to intra-individually compare two low-risk macrocyclic contrast agents with respect to dynamic and quantitative assessment of peak enhancement/signal intensity in benign and malignant breast lesions.

52 female patients referred to breast MRI for evaluation of focal lesions were included in a intraindividually controlled, randomized crossover study. Both contrast media were injected into the same cubital vein at a flow of 2 ml/sec using a dose of 0.1mmol/kg BW. The two examinations were done with minimum 24h up to 7 days in between. Dynamic T1 weighted 3D gradient echo sequences were performed under identical conditions using a 1.5T MR-Scanner and a 4-channel breast coil (Siemens Avanto, Erlangen). Quantitative evaluations to determine signal differences were performed. Differences between the two examinations were evaluated at analysis of covariance and tested for significance using the Wilcoxon Test. All lesions were histologically proven.

10 benign and 31 malignant lesions were assessed. The mean relative peak enhancement of all lesions and for the malignant lesions was statistically significantly higher for gadobutrol (264.84 vs. 204.29 all, p=0.0077; 265.02 vs. 203.97 malignant, p=0.024). Gadovist had significantly higher signal intensity values over the whole time period (p<.0001*) for all lesions and the malignant lesions. The shape of curves were not found to differ significantly (p=0.7860) Benign Lesions showed no significant differences.

Both contrast agents have reliable enhancement with a significantly stronger enhancement of gadobutrol. There is no difference in the shape of the timecurves. Thresholds of signal intensities regarding initial enhancement may have to be adjusted when using macrocyclic agents compared to linear agents. The impact on clinical outcome will be the focus of future research.

Due to NSF linear gadolinium containing agents are classified as high/medium risk and should be avoided esp. in renally impaired patients, macrocyclic agents are recommended but not tested in breast.

Fallenberg, E, Durmus, T, Diekmann, F, Renz, D, Engelken, F, Reles, A, Bick, U, Taupitz, M, Intra-Individual, Randomized Comparison of the MRI Contrast Agents Gadobutrol vs Gadoterate Meglumine in Breast MR Imaging.  Radiological Society of North America 2011 Scientific Assembly and Annual Meeting, November 26 - December 2, 2011 ,Chicago IL. http://archive.rsna.org/2011/11014968.html