title: Contrast-enhanced high resolution MRI for atherosclerotic carotid artery tissue characterization.
abstract: OBJECTIVE
  To determine if a gadolinium-based contrast agent provides additional information for characterization of human plaque tissues, particularly neovasculature. Although high-resolution magnetic resonance imaging (MRI) has been used to identify plaque constituents in advanced atherosclerosis, some constituents, such as neovascularized tissue, defy detection.
  
  
  METHODS
  Non-contrast-enhanced carotid artery images from 18 patients scheduled for carotid endarterectomy and two normal volunteers were used to identify regions of fibrous tissue, necrotic core, or calcification, using established criteria. Then, the percent change in T1-weighted images after contrast enhancement was calculated for each region.
  
  
  RESULTS
  There were statistically significant differences in mean intensity change between tissues, with the largest increase for fibrous tissue (79.5%) and the smallest for necrotic core (28.6%). Additionally, histological analysis showed that a subset of fibrous regions rich in plaque neovascularization could be identified using a threshold of 80% enhancement (sensitivity = 76%, specificity = 79%).
  
  
  CONCLUSIONS
  The ability of contrast-enhanced MRI to identify neovascularization and potentially improve differentiation of necrotic core from fibrous tissue further establishes MRI as a viable tool for in vivo study of atherosclerotic plaque.
authors.affiliation: University of Washington, School of Medicine, Seattle, Washington 98195-7115, USA. cyuan@u.washington.edu
authors.forename: Chun
authors.initials: C
authors.lastname: Yuan
authors.forename: William S
authors.initials: WS
authors.lastname: Kerwin
authors.forename: Marina S
authors.initials: MS
authors.lastname: Ferguson
authors.forename: Nayak
authors.initials: N
authors.lastname: Polissar
authors.forename: Shaoxiong
authors.initials: S
authors.lastname: Zhang
authors.forename: Jianming
authors.initials: J
authors.lastname: Cai
authors.forename: Thomas S
authors.initials: TS
authors.lastname: Hatsukami
mesh_terms: D000704:Analysis of Variance; D001161:Arteriosclerosis / Q000473:pathology*; D002340:Carotid Artery Diseases / Q000473:pathology* / Q000601:surgery; D016022:Case-Control Studies; D003287:Contrast Media / Q000008:administration & dosage; D016894:Endarterectomy, Carotid; D019786:Gadolinium DTPA / Q000008:administration & dosage; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods*; D009389:Neovascularization, Pathologic / Q000473:pathology; D012680:Sensitivity and Specificity
chemical_list: D003287:Contrast Media; C064925:gadodiamide; D019786:Gadolinium DTPA