title: "Brush Sign" on susceptibility-weighted MR imaging indicates the severity of moyamoya disease.
abstract: OBJECTIVE
  SWI is a high spatial resolution MR imaging technique showing magnetic inhomogeneity that could demonstrate increased oxygen extraction in focal cerebral ischemia. The aim of this study was to investigate the characteristics in the signal intensity of DMVs by using SWI and to determine whether this method could indicate the severity of the hemodynamics in MMD by evaluating the correlation between SWI stage and hemodynamics on SPECT.
  
  
  METHODS
  Consecutive MMD patients were prospectively analyzed before treatment. Routine MR imaging including SWI was performed, and the number of the conspicuous DMVs draining into the subependymal veins was classified: stage 1, mild (< 5); stage 2, moderate (5-10); and stage 3, severe (> 10). The SWI stage was evaluated in correlation with clinical presentations, and CBF and CVR were quantified by using a SPECT iodine 123 N-isopropyl-p-iodoamphetamine split-dose method.
  
  
  RESULTS
  Patients were 12 males and 21 females (range, 8-66 years), consisting of 4 asymptomatic patients, 13 patients with TIA, 9 patients with infarct, and 7 patients with hemorrhage. There was a significant difference in CVR among clinical presentations, though there was no difference in age, Suzuki stage, or CBF. Conversely, SWI stage was significantly higher in patients with TIA and infarct than asymptomatic patients (P < .01). Higher SWI stage significantly had lower CBF and CVR in the middle cerebral artery area (P < .05).
  
  
  CONCLUSIONS
  SWI stage strongly correlates with ischemic presentations in MMD and also correlates with hemodynamics on SPECT, especially CVR. Increased conspicuity of DMVs, known as "brush sign", could predict the severity of MMD.
authors.affiliation: Department of Neurosurgery, Nagasaki University School of Medicine, Nagasaki, Japan. nobstanford@gmail.com
authors.forename: N
authors.initials: N
authors.lastname: Horie
authors.forename: M
authors.initials: M
authors.lastname: Morikawa
authors.forename: A
authors.initials: A
authors.lastname: Nozaki
authors.forename: K
authors.initials: K
authors.lastname: Hayashi
authors.forename: K
authors.initials: K
authors.lastname: Suyama
authors.forename: I
authors.initials: I
authors.lastname: Nagata
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002543:Cerebral Hemorrhage / Q000000981:diagnostic imaging / Q000473:pathology / Q000503:physiopathology; D002544:Cerebral Infarction / Q000000981:diagnostic imaging / Q000473:pathology / Q000503:physiopathology; D002560:Cerebrovascular Circulation; D002648:Child; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009072:Moyamoya Disease / Q000000981:diagnostic imaging / Q000473:pathology* / Q000503:physiopathology*; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012720:Severity of Illness Index; D015899:Tomography, Emission-Computed, Single-Photon; D055815:Young Adult