title: Childhood posterior circulation arterial ischemic stroke.
abstract: OBJECTIVE
  Limited data exist on childhood posterior circulation arterial ischemic stroke (PCAIS). We describe clinical and radiological features of childhood PCAIS to determine whether there are differences in infarct topography, vascular abnormalities, risk factors, and stroke subtypes when compared to adults.
  
  
  METHODS
  Children with radiologically confirmed PCAIS were prospectively identified from August 2002 to February 2008. Infarcts were divided into proximal, middle, and distal posterior circulation segments utilizing an adult topographical classification system. Vascular abnormalities were described in terms of location, severity, and evolution over time. A pediatric modification of the TOAST classification system was used to define stroke subtypes.
  
  
  RESULTS
  Twenty seven (37%) of 73 children recruited to our registry had 34 radiologically confirmed PCAIS events. Infarct location was distal (25), middle (2), proximal (1), and multiple segments (6). Fourteen events were associated with single infarcts and 20 were associated with multiple infarcts. Magnetic resonance angiography was abnormal in 16 of 25 children with PCAIS at presentation with stenosis (8) or occlusion (8). Vascular lesions progressed (5), transiently worsened before stabilizing (2), remained stable or improved (8), or normalized (1) over 12 months. Stroke subtypes included nonprogressive steno-occlusive cerebral arteriopathy (9), cardioembolic (4), dissection (3), Moyamoya syndrome (3), other determined (4), probable (1), and undetermined etiology (3). Fifty-two percent of children had recurrent posterior (6) or anterior (8) strokes.
  
  
  CONCLUSIONS
  Nonprogressive arteriopathies are the most common cause of childhood PCAIS, usually affecting distal segments. Atherosclerosis-related risk factors do not play an important role in stroke causation. PCAIS is frequently associated with recurrent events.
authors.affiliation: Children's Neuroscience Centre, Royal Children’s Hospital Melbourne, Melbourne, Australia. mark.mackay@rch.org.au
authors.forename: Mark T
authors.initials: MT
authors.lastname: Mackay
authors.forename: Sanjay P
authors.initials: SP
authors.lastname: Prabhu
authors.forename: Lee
authors.initials: L
authors.lastname: Coleman
mesh_terms: D000293:Adolescent; D020520:Brain Infarction / Q000209:etiology* / Q000473:pathology; D002560:Cerebrovascular Circulation; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D020765:Intracranial Arterial Diseases / Q000150:complications* / Q000473:pathology; D018810:Magnetic Resonance Angiography; D008297:Male; D012042:Registries; D012307:Risk Factors; D012720:Severity of Illness Index