Bernhard Meyer MD, Presenter: Research Consultant, Pro Medicus Limited Research grant, Siemens AG Research grant, Bracco Group Research grant, Bayer AG

Bernd B. Frericks MD, Abstract Co-Author: Nothing to Disclose

Matthias Taupitz MD, PhD, Abstract Co-Author: Investigator, Copenhagen Malmo Contrast AB, Lund, Sweden

Karl-Juergen Wolf MD, Abstract Co-Author: Nothing to Disclose

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

Vasovist (gadofosveset trisodium, Bayer-Schering, Germany) is a blood pool agent for MRA. In addition to conventional first pass arterial phase MRA (FP), high resolution steady state (SS) imaging is performed during the blood pool phase of Vasovist. This prospective study was performed to assess if FP combined with SS imaging provides relevant additional information compared to FP alone.

82 patients with peripheral arterial occlusive disease were included. After bolus tracking, step-by-step FP was performed (9 ml Vasovist at 1ml/s and 30 ml normal saline at 0.5ml/s) using an Avanto scanner (Siemens) and 3D T1w sequences at 0.9x0.9x1.5 voxel size followed by high resolution SS imaging at 0.65x0.65x0.65mm voxel size. In 14 patients, additional DSA was performed within 4 weeks of MRA. Two off-site blinded reader first assessed first pass MRA and then first pass MRA combined with steady state imaging in terms of diagnostic confidence and maximum degree of segmental stenosis if DSA was available. DSA served as gold standard (one blinded reader).

813 below knee arterial segments were assessed (excluding pedal arteries). On FP, 97.5%(reader1) and 87.5%(reader2) of segments were considered diagnostic. FP+SS provided diagnostic images in 99.1%( p<0.05) and 98.0%(p<0.05). Above the knee, 97% and 95% of 401 arterial levels were diagnostic on FP and 100%(p<0.05) and 99%(P<0.05) on FP+SS. In 9.8% and 18.7% of segments/levels, additional information was provided by SS (better assessment of lesion morphology or lumen in stent). A total of 117 vessels were covered by MRA and DSA. Grading of these showed complete agreement in 79%(reader1) and 80%(reader2) between DSA and FP and in 78% and in 81% between FP+SS and DSA. Sensitivity for the detection of relevant stenoses (>50%) was 80% and 73% on FP and 77% and 78% on FP+SS; specificity was 96% and 97% for FP and did not change on FP+SS.  

The addition of SS to FP pass imaging increased the number of diagnostic segments in a relatively small but significant proportion for both readers.

Combined FP+SS MRA with Vasovist increases the number of assessable vessels and improves the validity of the examination.

Meyer, B, Frericks, B, Taupitz, M, Wolf, K, Albrecht, T, Peripheral MRA with a Blood Pool Contrast Agent Comparison of First Pass MRA Alone and Combined First Pass and Blood Pool MRA.  Radiological Society of North America 2009 Scientific Assembly and Annual Meeting, November 29 - December 4, 2009 ,Chicago IL. http://archive.rsna.org/2009/8016150.html