title: Patterns of cerebral ischemia in children with moyamoya.
abstract: BACKGROUND
  Moyamoya disease is characterized by progressive cerebrovascular stenosis with recurrent cerebral ischemic events. Transient ischemic attacks are often associated with hyperventilation in children with moyamoya, suggesting hypoperfusion rather than thrombotic vaso-occlusion as a prominent mechanism. The patterns of ischemia and severity of steno-occlusive disease in such children may elucidate these mechanisms.
  
  
  METHODS
  Children, 1 month to 18 years, with moyamoya, observed over 11 years were analyzed. A study neuroradiologist reviewed all presurgical neuroimaging. Ischemic injury was categorized into cortical, subcortical, and watershed infarction. Angiographic findings were staged using a standardized method.
  
  
  RESULTS
  Twenty children, 15 girls, median age 6.4 years, were included. All children had magnetic resonance imaging and angiography, and in 16, conventional angiography was available. All 40 hemispheres, in 20 children, were evaluated. The initial clinical presentation included neurological deficits in 17, recurrent transient ischemic attacks in 7, headache in 8, seizures in 8, and alteration in consciousness in 4 children. Infarcts were bilateral in 13 (65%) children (ischemia alone in 14, ischemic stroke with hemorrhagic transformation in two, and primary hemorrhage in two). Infarcts were cortical and/or subcortical in 13 (65%), both deep and cortical watershed in 11 (55%), and cortical watershed alone in 5 (25%) children. The predominant vascular territory involved was the middle cerebral artery. The internal carotid arterial system was involved in all, with stage IV being the most frequent angiographic stage.
  
  
  CONCLUSIONS
  Ischemic injury in deep watershed zones is common in childhood moyamoya and may reflect non-vaso-occlusive ischemic mechanisms. Location and severity of vascular involvement may correlate with various patterns of ischemic infarction in moyamoya disease and requires further study.
authors.affiliation: Section of Pediatric Neurology, Department of Pediatrics and Child Health, Childrens Hospital Winnipeg, University of Manitoba, Winnipeg, Manitoba, Canada. Electronic address: mubeen.rafay@utoronto.ca.
authors.forename: Mubeen F
authors.initials: MF
authors.lastname: Rafay
authors.affiliation: Department of Radiology, Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Derek
authors.initials: D
authors.lastname: Armstrong
authors.affiliation: Department of Surgery, Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Peter
authors.initials: P
authors.lastname: Dirks
authors.affiliation: Division of Neurology, Department of Pediatrics, Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Daune L
authors.initials: DL
authors.lastname: MacGregor
authors.affiliation: Division of Neurology, Department of Pediatrics, Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada; Population Health Sciences Program, Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Gabrielle
authors.initials: G
authors.lastname: deVeber
mesh_terms: D000293:Adolescent; D001921:Brain / Q000098:blood supply / Q000473:pathology*; D002545:Brain Ischemia / Q000473:pathology* / Q000503:physiopathology* / Q000628:therapy; D002533:Cerebral Angiography; D002648:Child; D002675:Child, Preschool; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008279:Magnetic Resonance Imaging; D008297:Male; D009072:Moyamoya Disease / Q000473:pathology* / Q000503:physiopathology* / Q000628:therapy; D020521:Stroke / Q000473:pathology / Q000503:physiopathology / Q000628:therapy; D014057:Tomography, X-Ray Computed
keywords: cognition; ischemic infarction; moyamoya; outcome; pathogenesis; pattern of injury; pediatric