title: Is a fetal origin of the posterior cerebral artery a risk factor for TIA or ischemic stroke? A study with 16-multidetector-row CT angiography.
abstract: OBJECTIVE
  Fetal origin of the posterior cerebral artery (PCA) is not uncommon. Whether patients with this anomaly have a higher risk of ischemic stroke in the territory of the PCA is not known. The clinical benefit of screening for a fetal origin in patients with TIA or stroke in the territory of the PCA and an ipsilateral atherosclerotic carotid stenosis is not clear. This study assessed the frequency of a fetal origin of the PCA in patients with a TIA or infarct in the territory of the PCA with 16-multidetector-row CT angiography (CTA).
  
  
  METHODS
  82 patients (52 male; mean age = 64; range 19 to 90 years) with isolated homonymous hemianopia and/or a PCA infarct underwent CTA of the carotid artery and circle of Willis.
  
  
  RESULTS
  A fetal origin of the PCA at the symptomatic side was present in 14 patients (17 %) and at the asymptomatic side in 18 patients (22%) (OR: 0.7; 95 % CI: 0.3 to 1.7). Severity of stenosis (NASCET criteria) of the ICA at the symptomatic side was < 30%, 30-49% and > or = 50% in 72, 2 and 8 patients, respectively. Number and frequency of a fetal origin in these groups were 12 (17 %), 0 (0%) and 2 (25 %), respectively. There was no association between a severe carotid stenosis and a fetal origin of the PCA at the symptomatic side.
  
  
  CONCLUSIONS
  This study does not provide arguments for an increased risk of ischemic stroke in the territory of the PCA in patients with a fetal origin of the PCA. A few patients with a TIA or infarct in the territory of the PCA have a fetal origin of the PCA in combination with a high-grade stenosis of the ipsilateral ICA, but not more often than one would expect from chance. Nevertheless, these patients may benefit from carotid endarterectomy.
authors.affiliation: Department of Radiology, Erasmus MC, University Medical Center, 's Gravendijkwal 230, Rotterdam, The Netherlands.
authors.forename: Cécile
authors.initials: C
authors.lastname: de Monyé
authors.forename: Diederik W J
authors.initials: DW
authors.lastname: Dippel
authors.forename: Theodora A M
authors.initials: TA
authors.lastname: Siepman
authors.forename: Marcel L
authors.initials: ML
authors.lastname: Dijkshoorn
authors.forename: Hervé L J
authors.initials: HL
authors.lastname: Tanghe
authors.forename: Aad
authors.initials: A
authors.lastname: van der Lugt
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D050197:Atherosclerosis / Q000209:etiology; D002545:Brain Ischemia / Q000150:complications* / Q000453:epidemiology* / Q000473:pathology; D002533:Cerebral Angiography; D003627:Data Interpretation, Statistical; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D020762:Infarction, Posterior Cerebral Artery / Q000473:pathology; D002546:Ischemic Attack, Transient / Q000150:complications* / Q000000981:diagnostic imaging / Q000453:epidemiology*; D008297:Male; D008875:Middle Aged; D020769:Posterior Cerebral Artery / Q000002:abnormalities* / Q000000981:diagnostic imaging; D012189:Retrospective Studies; D012307:Risk Factors; D020521:Stroke / Q000453:epidemiology* / Q000209:etiology* / Q000473:pathology; D014057:Tomography, X-Ray Computed