title: Headache following cervical sympathectomy and results of a blood flow study in the cat.
abstract: BACKGROUND
  A patient developed severe, continuous, unilateral headache that was "vascular" in nature, following cervical sympathectomy.
  
  
  OBJECTIVE
  To determine the changes in cranial blood flow in the cat following lesioning and stimulation of the cervical sympathetic nerve.
  
  
  METHODS
  Carotid blood flow was determined by electromagnetic flowmetry and its tissue distribution by intra-arterial injection of 15-microm radioactive microspheres.
  
  
  RESULTS
  Following sympathetic lesioning, an increase in carotid blood flow was observed and reversed with stimulation. The distribution of carotid blood flow changed for the brain only, maintaining relatively constant tissue perfusion.
  
  
  CONCLUSIONS
  An increase in cerebral blood flow could not have accounted for the sympathectomy-induced headache. Dilation of major cerebral arteries and cranial noncerebral vasodilation probably constitutes its mechanism.
authors.affiliation: Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
authors.forename: Egilius L H
authors.initials: EL
authors.lastname: Spierings
mesh_terms: D000818:Animals; D001783:Blood Flow Velocity; D002339:Carotid Arteries / Q000503:physiopathology*; D002415:Cats; D002560:Cerebrovascular Circulation; D006801:Humans; D008297:Male; D008863:Microspheres; D008875:Middle Aged; D012019:Reflex Sympathetic Dystrophy / Q000601:surgery; D013562:Sympathectomy / Q000009:adverse effects*; D014653:Vascular Headaches / Q000209:etiology / Q000503:physiopathology*