title: Relationship between carotid artery remodeling and plaque vulnerability with T1-weighted magnetic resonance imaging.
abstract: BACKGROUND
  The aim of this study was to validate the relationship between carotid artery remodeling defined as the carotid remodeling index (CRI) and plaque vulnerability by comparing the degree of outward remodeling calculated using 3-dimensional inversion recovery-based T1-weighted imaging (magnetization-prepared rapid acquisition gradient echo [MPRAGE]) with the symptomatology and histology of plaques extracted during carotid endarterectomy.
  
  
  METHODS
  Sixty-one patients with 50% stenosis or more (North American Symptomatic Carotid Endarterectomy Trial criteria) were included. The average rate of stenosis was 79.8%. The CRI was determined by measuring the external cross-sectional vessel area (CSVA) at the maximum stenosis of the internal carotid artery (ICA) and dividing it by the external CSVA at the distal ICA (unaffected by atherosclerosis) using MPRAGE imaging.
  
  
  RESULTS
  The CRI was significantly higher in symptomatic patients compared with asymptomatic patients (1.98±.26 versus 1.68±.24, P<.0001). A higher CRI positively correlated with the necrotic core area (r=.57, P<.0001) and negatively correlated with the fibrous cap thickness (r=-.33, P=.01). It was also significantly associated with severe intraplaque hemorrhage (P<.0001) and the prevalence of cap inflammation with macrophage (P=.03) and lymphocyte (P=.01) infiltration.
  
  
  CONCLUSIONS
  The larger outward remodeling of the carotid artery on MPRAGE imaging had symptomatic carotid plaques and histologically vulnerable plaques. This study indicates that MPRAGE imaging is useful for the assessment of carotid artery remodeling.
authors.affiliation: Department of Neurosurgery, National Cerebral and Cardiovascular Center, Osaka, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Fukuda
authors.affiliation: Department of Neurosurgery, National Cerebral and Cardiovascular Center, Osaka, Japan. Electronic address: kiihara@ns.med.kyushu-u.ac.jp.
authors.forename: Koji
authors.initials: K
authors.lastname: Iihara
authors.affiliation: Department of Neurosurgery, National Cerebral and Cardiovascular Center, Osaka, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Maruyama
authors.affiliation: Department of Radiology, National Cerebral and Cardiovascular Center, Osaka, Japan.
authors.forename: Naoaki
authors.initials: N
authors.lastname: Yamada
authors.affiliation: Department of Pathology, National Cerebral and Cardiovascular Center, Osaka, Japan.
authors.forename: Hatsue
authors.initials: H
authors.lastname: Ishibashi-Ueda
mesh_terms: D000368:Aged; D002339:Carotid Arteries / Q000473:pathology* / Q000601:surgery; D016893:Carotid Stenosis / Q000473:pathology* / Q000601:surgery; D003430:Cross-Sectional Studies; D016894:Endarterectomy, Carotid; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D058226:Plaque, Atherosclerotic / Q000473:pathology* / Q000601:surgery
keywords: Carotid artery stenosis; MR imaging; carotid remodeling index; outward remodeling; plaque vulnerability