title: Horner's syndrome resulting from agenesis of the internal carotid artery: report of a third case.
abstract: BACKGROUND
  Only two previous reports of agenesis of the internal carotid artery with a coexistent Horner's syndrome are to be found in the medical literature.
  
  
  METHODS
  We report a case of a male child seen initially for what was presumed to be a traumatic superficial temporal artery aneurysm. MRA incidentally revealed ipsilateral agenesis of the internal carotid artery. This child's physical exam included ipsilateral Horner's syndrome.
  
  
  CONCLUSIONS
  This case report illustrates that agenesis of the internal carotid artery does indeed cause Horner's syndrome in some cases. The clinician who diagnoses a patient with Horner's syndrome should remember that agenesis of the internal carotid artery may be the cause as this entity can be associated in itself with other pathologies of the central nervous system.
authors.affiliation: Department of Cell Biology, University of Alabama at Birmingham, Birmingham, Alabama, USA. richard.tubbs@ccc.uab.edu
authors.forename: R Shane
authors.initials: RS
authors.lastname: Tubbs
authors.forename: W Jerry
authors.initials: WJ
authors.lastname: Oakes
mesh_terms: D000783:Aneurysm / Q000150:complications / Q000473:pathology; D002340:Carotid Artery Diseases / Q000150:complications*; D002533:Cerebral Angiography / Q000379:methods; D002648:Child; D006732:Horner Syndrome / Q000209:etiology* / Q000473:pathology; D006801:Humans; D018810:Magnetic Resonance Angiography / Q000379:methods; D008297:Male; D014057:Tomography, X-Ray Computed / Q000379:methods