title: Diffuse cerebrovascular dilation: Case report of amezinium metilsulfate-induced reversible cerebral vasoconstriction syndrome.
abstract: BACKGROUND
  Reversible cerebral vasoconstriction syndrome (RCVS) is characterized by recurrent thunderclap headaches with reversible cerebral vasoconstriction, and often precipitated by the postpartum state and vasoactive medications. We describe a case of a patient with RCVS induced by amezinium metilsulfate, a sympathomimetic drug, in whom magnetic resonance angiography (MRA) initially revealed diffusely dilated cerebral arteries.
  
  
  METHODS
  A 34-year-old woman was prescribed amezinium metilsulfate for hypotension. Twelve days later, she suffered from abrupt severe headaches and was referred to our department. She had no neurological deficits; however, MRA revealed diffusely dilated anterior, middle, and posterior cerebral arteries with vasoconstriction. She was tentatively diagnosed with RCVS and successfully treated with verapamil for headache. Nevertheless, follow-up MRAs disclosed widespread segmental vasoconstriction that resolved in two months.
  
  
  CONCLUSIONS
  Diffuse cerebrovascular dilation has not been addressed but may be associated with RCVS pathophysiology. In addition, physicians should bear in mind that amezinium metilsulfate can potentially induce RCVS.
authors.affiliation: Department of Neurology, Asahi General Hospital, Japan ma-ko@pg7.so-net.ne.jp.
authors.forename: Makoto
authors.initials: M
authors.lastname: Kobayashi
mesh_terms: D000328:Adult; D001921:Brain / Q000098:blood supply*; D005260:Female; D051270:Headache Disorders, Primary / Q000139:chemically induced*; D006801:Humans; D007022:Hypotension / Q000188:drug therapy; D018810:Magnetic Resonance Angiography; D011724:Pyridazines / Q000009:adverse effects*; D013566:Sympathomimetics / Q000009:adverse effects*; D014661:Vasoconstriction / Q000502:physiology; D014664:Vasodilation / Q000502:physiology; D020301:Vasospasm, Intracranial / Q000139:chemically induced*
chemical_list: D011724:Pyridazines; D013566:Sympathomimetics; C027784:amezinium
keywords: Amezinium metilsulfate; cerebrovascular dilation; magnetic resonance angiography; reversible cerebral vasoconstriction syndrome