Jochen Martin Grimm MD, Presenter: Nothing to Disclose

Andreas Schindler, Abstract Co-Author: Nothing to Disclose

Tobias Freilinger, Abstract Co-Author: Nothing to Disclose

Clemens Christian Joachim Cyran MD, Abstract Co-Author: Research grant, Bayer AG

Chun Yuan PhD, Abstract Co-Author: Research grant, Koninklijke Philips Electronics NV

Konstantin Nikolaou MD, Abstract Co-Author: Speakers Bureau, Siemens AG Speakers Bureau, Bracco Group Speakers Bureau, Bayer AG

Martin Dichgans, Abstract Co-Author: Nothing to Disclose

Maximilian F. Reiser MD, Abstract Co-Author: Nothing to Disclose

Tobias Saam MD, Abstract Co-Author: Research grant, Diamed Medizintechnik GmbH

To determine if high-resolution 3T magnetic resonance imaging (hr-MRI) can depict differences between symptomatic and asymptomatic carotid atherosclerotic plaques.

In this prospective monocentric observational study 34 patients (7 females; 70±9.3 years) with acute symptomatic carotid disease defined as ischemic brain lesions in one carotid artery territory on diffusion weighted images underwent a carotid black-blood hr-MRI at 3.0-Tesla with fat-saturated pre- and post-contrast T1w-, PDw-, T2w- and TOF images using surface coils and Parallel Imaging techniques (PAT factor=2) within 7 days after symptom onset. All patients underwent extensive clinical workup (lab, brain MRI, duplex sonography, 24-hour ECG, transoesophageal echocardiography) to exclude other causes of ischemic stroke. Prevalence of American Heart Association lesion type VI (AHA-LT6) and thrombus, status of the fibrous cap, presence and type of hemorrhage were qualitatively and quantitatively determined in both carotid arteries based on previously published MRI criteria by two reviewers in consensus who were blinded to the clinical information. The Mc Nemar Test was used for statistical comparison. A p-value <0.05 was considered statistically significant.

Symptomatic plaques, compared to asymptomatic plaques, had a higher prevalence of AHA-LT6 (65.5% vs. 10.3%; P<0.001), ruptured/ulcerated fibrous caps (34.5% vs. 3.5%; P=0.012), plaque hemorrhage (58.6% vs. 10.3%; P=0.001), early subacute hemorrhage (27.6% vs. 0%; P=0.008) and juxtaluminal thrombus (10.3% vs. 0%; p=n.s.). Quantitatively, maximum necrotic core and hemorrhage area were greater in symptomatic than in asymptomaitc plaques (13.6 mm² vs. 5.5 mm² and 8.0 mm² vs. 1.3 mm² with p<0.01), while mean vessel and lumen areas did not significantly differ between both groups.  

3T hr-MRI is able to differentiate between symptomatic and asymptomatic carotid plaques, demonstrating the high potential of hr-MRI to differentiate between stable and vulnerable lesions and ultimately to identify patients with low versus high risk for cardiovascular complications.

3T hr-MRI is a potent tool in the differentiation between stable and vulnerable lesions and can ultimately help identify patients who are likely to benefit from interventional or surgical therapy.

Grimm, J, Schindler, A, Freilinger, T, Cyran, C, Yuan, C, Nikolaou, K, Dichgans, M, Reiser, M, Saam, T, Comparison of Symptomatic and Asymptomatic Atherosclerotic Carotid Plaques Using Parallel Imaging and 3 T High-Resolution in Vivo MR Imaging.  Radiological Society of North America 2011 Scientific Assembly and Annual Meeting, November 26 - December 2, 2011 ,Chicago IL. http://archive.rsna.org/2011/11004087.html