Antoine Millon1, Jean-Louis Mathevet1, Loic Boussel1, Zahi Fayad2, Peter Faries2, Patrick Feugier1, Philippe Douek1
1University Hospital of Lyon, France, Lyon, France; 2Mount Sinai Hospital, New York, NY.
OBJECTIVES: Carotid Magnetic Resonance Imaging (MRI) may be a useful tool to characterize carotid plaque vulnerability, but large studies are still lacking. The purpose of this study is to assess carotid MRI features of vulnerable plaque in a large study and assess changes in carotid plaque morphology with time since neurologic event.
METHODS: We included 161 patients with carotid plaque. All underwent a carotid MRI using 3T High Resolution MR sequences. Stenosis degree, plaque thickness, plaque type (lipidic, fibrotic, calcified), Intra-plaque hemorrhage (IPH), fibrous cap rupture (FCR) and gadolinium enhancement (GE) were assessed. Plaque type was classified on the basis of the predominant component of the plaque. IPH, FCR and GE were classified as absent or present.
RESULTS: Seven patients were excluded because of poor image quality. In the 154 remaining patients, 52 were symptomatic (41 strokes, 7 transient ischemic attacks and 4 amaurosis in the last 6 months) and 102 asymptomatic. IPH (39 vs. 16% ; p=0.002), FCR (30 vs. 9% ; p<0.0001), GE (77 vs. 55% ; p=0.014) were significantly higher in symptomatic vs. asymptomatic plaque. No difference were observed for stenosis degree or plaque thickness. Plaques with extensive calcification were observed more frequently in asymptomatic patients (43 vs. 22% ; p=0.014). IPH is significantly higher in symptomatic plaque regardless of the time since the neurologic event. For FCR difference between symptomatic and asymptomatic are significant only during the first 15 days following the neurological event.
CONCLUSIONS: Carotid MRI can identify plaque features that are associated with symptomatic presentation and may be indicative of plaque vulnerability. These features may ultimately be utilized in the management of extracranial carotid stenosis.
AUTHOR DISCLOSURES: L. Boussel, Nothing to disclose, P. Douek: Nothing to disclose, P. Faries, Nothing to disclose; Z. Fayad, Nothing to disclose; P. Feugier, Nothing to disclose; J. Mathevet, Nothing to disclose; A. Millon, Nothing to disclose.
Posted April 2012