Niels Zorger MD, Presenter: Nothing to Disclose

Andreas G Schreyer MD, Abstract Co-Author: Nothing to Disclose

Ernst Michael Jung MD, Abstract Co-Author: Nothing to Disclose

Thomas Herold MD, Abstract Co-Author: Nothing to Disclose

Stefan G.E. Feuerbach MD, Abstract Co-Author: Nothing to Disclose

Florian Poschenrieder MD, Abstract Co-Author: Nothing to Disclose

The aim of this study was to compare the accuracy of a new developed intraarterial MR angiography with iv. MR angiography for the detection of infrainguinal stenoses.

Twenty patients underwent digital substraction angiography (DSA), iv MR angiography, and intraarterial MR angiography before balloon angioplasty. For intraarterial MR angiography, 30 mL of diluted contrast agent (5 mL of gadodiamide diluted in 55 mL of 0.9% saline solution) was injected through a sheath in the superficial femoral artery using a flow rate of 2.5 mL/sec. For iv MR angiography 27 mL undiluted contrast agent (gadopentetate) was injected through a venous access using a flow rate of 1.0 mL/sec and a care bolus technique. A 3D gradient-echo sequence was performed in both. Three blinded observers assessed differences in the quantitative measurement of stenoses and localization of lesions between itraarterial and iv MR angiography. The overall impression was documented on a 4-point scale (1=excellent, 4=poor). DSA was used as reference standard. Interobserver variability was calculated.

For detection of significant stenoses (> 50% stenosis), the overall sensitivity/specificity for the femoropopliteal and crural vessels were 85%/83% and 92%/75% using intraarterial MR angiograpy and 82%/87% and 87%/87% using iv MR angiography. The mean overall impression of all segments was 1.35 (SD, 0.68) for intaarterial and 1.58 (SD, 0.72) for iv MR angiography. The differences between the kappa values of all observers for the intraarterial and intravenous technique was not statistically significant when assessed with the two-tailed Wilcoxon´s rank sum test.

Intraarterial MR angiography of the infrainguinal arteries provides a sensitivity and specificity comparable to the intravenous technique with an improved assessment of the infrapopliteal arteries using only a very low dosage of contrast agent.

The new developed intraarterial MRA of the infrainguinal arteries provides a sensitivity/specificity comparable to the iv MRA. This technique may play a key role in MR-guided endovascular interventions.

Zorger, N, Schreyer, A, Jung, E, Herold, T, Feuerbach, S, Poschenrieder, F, Intraarterial versus Intravenous Gadolinium-enhanced MR Angiography in Humans for the Detection of Infrainguinal Arterial Stenoses.  Radiological Society of North America 2007 Scientific Assembly and Annual Meeting, November 25 - November 30, 2007 ,Chicago IL. http://archive.rsna.org/2007/5011098.html