title: Middle cerebral artery intraplaque hemorrhage: prevalence and clinical relevance.
abstract: OBJECTIVE
  Little is known about the composition of middle cerebral artery (MCA) plaques and how they relate to clinical status. Using high-resolution magnetic resonance imaging (HR-MRI), we aimed to examine the occurrence of high signal on T1-weighted fat-suppressed images (HST1) of MCA plaques, which are highly suggestive of fresh or recent intraplaque hemorrhage.
  
  
  METHODS
  We retrospectively analyzed the HR-MRI and clinical data of 107 adult patients with high-grade (>70%) MCA stenosis. On HR-MRI, HST1 within an MCA plaque was defined as an area with an intensity >150% of the signal of adjacent muscles. The relationship between HST1 and clinical presentations was analyzed.
  
  
  RESULTS
  A total of 109 stenotic MCAs (46 symptomatic and 63 asymptomatic) on 981 image slices were analyzed. HST1 was revealed on HR-MRI in 11 vessels (10.1%, 9 symptomatic and 2 asymptomatic). The occurrence rate of HST1 between symptomatic and asymptomatic MCAs was significantly different (19.6% vs 3.2%, p = 0.01).
  
  
  CONCLUSIONS
  HST1 within MCA plaque on HR-MRI is associated with ipsilateral stroke. Our results provide new insight into the vascular biology of MCA atherosclerosis.
authors.affiliation: Department of Neurology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China. xuwhpumch@yahoo.com.cn
authors.forename: Wei-Hai
authors.initials: WH
authors.lastname: Xu
authors.forename: Ming-Li
authors.initials: ML
authors.lastname: Li
authors.forename: Shan
authors.initials: S
authors.lastname: Gao
authors.forename: Jun
authors.initials: J
authors.lastname: Ni
authors.forename: Ming
authors.initials: M
authors.lastname: Yao
authors.forename: Li-Xin
authors.initials: LX
authors.lastname: Zhou
authors.forename: Bin
authors.initials: B
authors.lastname: Peng
authors.forename: Feng
authors.initials: F
authors.lastname: Feng
authors.forename: Zheng-Yu
authors.initials: ZY
authors.lastname: Jin
authors.forename: Li-Ying
authors.initials: LY
authors.lastname: Cui
mesh_terms: D003251:Constriction, Pathologic / Q000453:epidemiology / Q000473:pathology*; D006470:Hemorrhage / Q000453:epidemiology* / Q000473:pathology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D020768:Middle Cerebral Artery / Q000473:pathology*; D058226:Plaque, Atherosclerotic / Q000453:epidemiology / Q000473:pathology*; D015995:Prevalence; D012189:Retrospective Studies; D012720:Severity of Illness Index