Lale Umutlu MD, Presenter: Consultant, Bayer AG

Karsten Wrede, Abstract Co-Author: Nothing to Disclose

Christoph Moenninghoff MD, Abstract Co-Author: Nothing to Disclose

Philipp Dammann, Abstract Co-Author: Nothing to Disclose

Soren Johst, Abstract Co-Author: Nothing to Disclose

Michael Forsting MD, Abstract Co-Author: Nothing to Disclose

Marc U. Schlamann, Abstract Co-Author: Nothing to Disclose

With digital subtraction angiography remaining to be the gold-standard, 1.5 Tesla TOF MRA is known to offer high-quality, non-invasive assessment of AVM. Nevertheless, 1.5 TOF MRA shows limitations due to its restricted spatial resolution. Hence, the aim of this trial was to compare the diagnostic competence of ultra-high-resolution 7 Tesla TOF MRA with digital subtraction angiography (DSA) for assessment of AVM.

17 patients with known AVM underwent pretreatment DSA and a 7T MR examination (Magnetom 7T, Siemens Healthcare) obtaining an ultra-high-resolution TOF MRA (voxel size of 0.2 x 0.2 x 0.2mm3). Two readers in consensus evaluated the delineation of the AVM regarding the (1) nidus, (2) feeder, (3) drainer, (4) relationship between AVM and the adjacent brain structures, (5) vessel-tissue contrast as well as (6) artifact impairment for both datasets using a 5-point scoring system. Wilcoxon rank test was applied for assessment of statistical significance.

Both imaging modalities provided high-quality vessel delineation, showing comparably high ratings for the assessed features (DSA: mean nidus = 4.7; 7T: mean nidus = 4.6 // DSA: mean feeder vessel = 4.9; 7T mean feeder = 4.8). Furthermore, 7T TOF MRA allowed for high-quality assessment of the relationship between AVM and adjacent brain structures. Signal variations led to minor non-significant impairments of TOF MRA (mean 4.5).

Based on high vessel-tissue contrast and high spatial resolution, 7T TOF MRA bears the potential to be an equivalent non-invasive alternative to DSA with the benefit of sparing ionizing radiation and the application of contrast agent. Furthermore, it offers additional diagnostics of the relationship between AVM and adjacent brain structures.

7T TOF MRA may serve as a high-quality non-invasive alternative for assessment, pretherapeutic planning and follow-up of AVM, sparing ionizing radiation and the application of iodinated contrast agent.

Umutlu, L, Wrede, K, Moenninghoff, C, Dammann, P, Johst, S, Forsting, M, Schlamann, M, Competing with the Gold-standard: Ultra-high-Resolution TOF MRA at 7T versus DSA for Assessment of Arteriovenous Malformations.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14013107.html