title: T1-Weighted Magnetic Resonance Carotid Plaque Imaging: a Comparison between Conventional and Fast Spin-Echo Techniques.
abstract: BACKGROUND
  Magnetic resonance imaging is widely used to evaluate the intraplaque components of the cervical carotid artery. The non-gated T1-weighted spin-echo (SE) technique has been reported to have an excellent ability for discriminating stable and unstable plaques. However, the diagnostic performance of various SE-based techniques remains unclear. Hence, we compared plaque signals obtained by 3 kinds of SE-based methods with histological findings.
  
  
  METHODS
  We prospectively examined 40 patients who underwent carotid endarterectomy by using 1.5-T scanners and obtained 2-dimensional (2D) conventional spin-echo (CSE), 2D fast spin-echo (FSE), and 3-dimensional (3D)-FSE images with identical repetition times. We calculated contrast ratios (CRs) of the plaques against adjacent muscles and compared these values with the pathological classification of the specimens.
  
  
  RESULTS
  The CRs of type VII-VIII (calcific/fibrous), IV-V (lipid-rich/necrotic), and VI (complex/hemorrhagic) plaques were significantly different between all the methods (P <.001) and were discriminated from each other at sensitivities of 83%-100% and specificities of 94%-100%. The CRs of type IV-V plaques significantly differed between the methods (low to high, 2D-FSE, 2D-CSE, and 3D-FSE; P <.05); those of the type VI plaques were significantly lower with the 2D-FSE method than with the other methods (P <.01).
  
  
  CONCLUSIONS
  The SE-based T1-weighted images can readily discriminate plaque characteristics with high sensitivities and specificities, although the signal intensity of unstable plaques was significantly high on the 3D-FSE images and significantly low on the 2D-FSE images.
authors.affiliation: Department of Neurology and Gerontology, Iwate Medical University, Iwate, Japan. Electronic address: snarumi@iwate-med.ac.jp.
authors.forename: Shinsuke
authors.initials: S
authors.lastname: Narumi
authors.affiliation: Institute for Biomedical Sciences, Iwate Medical University, Iwate, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Sasaki
authors.affiliation: Department of Neurology and Gerontology, Iwate Medical University, Iwate, Japan.
authors.forename: Haruna
authors.initials: H
authors.lastname: Miyazawa
authors.affiliation: Department of Neurology and Gerontology, Iwate Medical University, Iwate, Japan.
authors.forename: Tatsunori
authors.initials: T
authors.lastname: Natori
authors.affiliation: Department of Neurology and Gerontology, Iwate Medical University, Iwate, Japan.
authors.forename: Kohei
authors.initials: K
authors.lastname: Ito
authors.affiliation: Department of Neurosurgery, Iwate Medical University, Iwate, Japan.
authors.forename: Kuniaki
authors.initials: K
authors.lastname: Ogasawara
authors.affiliation: Department of Neurosurgery, Iwate Medical University, Iwate, Japan.
authors.forename: Masakazu
authors.initials: M
authors.lastname: Kobayashi
authors.affiliation: Department of Anatomy, Iwate Medical University, Iwate, Japan.
authors.forename: Jiro
authors.initials: J
authors.lastname: Hitomi
authors.affiliation: Department of Neurology and Gerontology, Iwate Medical University, Iwate, Japan.
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Terayama
mesh_terms: D000368:Aged; D002339:Carotid Arteries / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D002340:Carotid Artery Diseases / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D003251:Constriction, Pathologic / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery; D003937:Diagnosis, Differential; D016894:Endarterectomy, Carotid; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D058226:Plaque, Atherosclerotic / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D011446:Prospective Studies; D012680:Sensitivity and Specificity
keywords: Carotid plaque; T1-weighted image; carotid endarterectomy; magnetic resonance imaging