title: High-Intensity Signal in Carotid Plaque on Routine 3D-TOF-MRA Is a Risk Factor of Ischemic Stroke.
abstract: BACKGROUND
  Carotid atherosclerotic disease is recognized as an important risk factor for brain ischemic events. However, high-grade stenosis does not always cause ischemic strokes, whereas moderate-grade stenosis may often cause ischemic strokes. It has been reported that there is an association between carotid intraplaque hemorrhage (IPH) and new cerebral ischemic events. The purpose of this study was to elucidate the relationship between high-intensity signals (HIS) on maximum intensity projection (MIP) images from routine 3-dimensional time-of-flight magnetic resonance angiography (3D-TOF-MRA) and prior ischemic strokes in the patients with moderate carotid stenosis.
  
  
  METHODS
  Sixty-one patients with moderate carotid artery stenosis (50-69% stenosis based on North American Symptomatic Carotid Endarterectomy Trial criteria) were included. Carotid IPH was defined as the presence of HIS in carotid plaques on MIP images detected by 3D-TOF-MRA using criteria we previously reported. We analyzed the relationship between the presence of HIS in plaques and prior ischemic strokes defined as ischemic lesions on diffusion-weighted brain images.
  
  
  RESULTS
  HIS in carotid plaques were present in 27 (44%) of 61 patients. Prior ipsilateral ischemic strokes occurred more frequently in the HIS-positive group than the HIS-negative group (67 vs. 9%, p < 0.001). Furthermore, there were more smokers in the group with ischemic stroke than without it (62 vs. 25%, p = 0.005). In multivariate logistic regression analysis, HIS in carotid plaque (OR 23.4, 95% CI 4.62-118.3, p < 0.001) and smoking (OR 5.44, 95% CI 1.20-24.6, p = 0.028) were independent determinants of prior ischemic strokes after adjustment for age.
  
  
  CONCLUSIONS
  HIS in carotid plaques on 3D-TOF-MRA MIP images are independent determinants of prior ischemic strokes in patients with moderate carotid artery stenosis, and they can potentially provide a reliable risk stratification of patients with moderate carotid artery stenosis.
authors.affiliation: Department of Neurosurgery, Sato Daiichi Hospital, Oita, Japan.
authors.forename: Kiyofumi
authors.initials: K
authors.lastname: Yamada
authors.forename: Masanori
authors.initials: M
authors.lastname: Kawasaki
authors.forename: Shinichi
authors.initials: S
authors.lastname: Yoshimura
authors.forename: Manabu
authors.initials: M
authors.lastname: Shirakawa
authors.forename: Kazutaka
authors.initials: K
authors.lastname: Uchida
authors.forename: Seigo
authors.initials: S
authors.lastname: Shindo
authors.forename: Shuji
authors.initials: S
authors.lastname: Nishida
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Iwamoto
authors.forename: Shigehiro
authors.initials: S
authors.lastname: Nakahara
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Sato
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002545:Brain Ischemia / Q000150:complications / Q000453:epidemiology*; D016893:Carotid Stenosis / Q000453:epidemiology* / Q000473:pathology; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D016015:Logistic Models; D018810:Magnetic Resonance Angiography; D008297:Male; D017853:Phosphotransferases (Alcohol Group Acceptor); D012189:Retrospective Studies; D012307:Risk Factors; D012907:Smoking / Q000453:epidemiology; D020521:Stroke / Q000453:epidemiology* / Q000209:etiology
chemical_list: C492429:AGK protein, human; D017853:Phosphotransferases (Alcohol Group Acceptor)