title: Staged bilateral vertebral artery occlusion for ruptured dissecting aneurysms of the basilar artery: a report of 2 cases.
abstract: BACKGROUND
  Dissecting aneurysm of the basillary artery BA is rare. Although mortality rate is high, management remains controversial. We report 2 cases of dissecting aneurysm of the BA presenting with subarachnoid hemorrhage (SAH), both of which were successfully treated using staged occlusion of bilateral vertebral arteries (VAs).
  
  
  METHODS
  A 64-year-old man and a 34-year-old woman presented with SAH associated with ruptured dissecting aneurysm of the BA. After endovascular occlusion of a single VA, blood flow in the dissected lumen was reduced. However, one aneurysm rebled and the bleb of the other did not change. Vertebral arteries were also occluded using endovascular techniques at 4 and 2 weeks after initial treatment, respectively. On the second intervention, stump pressure ratios of VAs intended for occlusion were 62.5% and 50.6%, respectively. The patients tolerated temporary occlusion of bilateral VAs well. Subsequent permanent occlusion of bilateral VAs resulted in no neurological complication. Complete obliteration of the aneurysmal lumen was demonstrated on magnetic resonance angiography performed 72 and 5 months later, respectively.
  
  
  CONCLUSIONS
  Staged bilateral VA occlusion might be the last recourse to prevent further hemorrhage from BA dissecting aneurysm. The technique can be safely applied when the stump pressure ratio is 50.6% or greater and when the patient tolerates temporary occlusion, which suggests the existence of sufficient collateral flow from the anterior circulation.
authors.affiliation: Department of Neurosurgery, Hiroshima University Graduate School of Biomedical Sciences, Hiroshima 734-8551, Japan. sakamoto@hiroshima-u.ac.jp
authors.forename: Shigeyuki
authors.initials: S
authors.lastname: Sakamoto
authors.forename: Shinji
authors.initials: S
authors.lastname: Ohba
authors.forename: Masaaki
authors.initials: M
authors.lastname: Shibukawa
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Kiura
authors.forename: Takahito
authors.initials: T
authors.lastname: Okazaki
authors.forename: Kazunori
authors.initials: K
authors.lastname: Arita
authors.forename: Kaoru
authors.initials: K
authors.lastname: Kurisu
mesh_terms: D000328:Adult; D000784:Aortic Dissection / Q000145:classification / Q000150:complications / Q000473:pathology* / Q000628:therapy*; D017542:Aneurysm, Ruptured / Q000145:classification / Q000150:complications / Q000473:pathology* / Q000628:therapy*; D004621:Embolization, Therapeutic; D005260:Female; D006801:Humans; D002532:Intracranial Aneurysm / Q000145:classification / Q000150:complications / Q000473:pathology* / Q000628:therapy*; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged; D012039:Regional Blood Flow; D013345:Subarachnoid Hemorrhage / Q000209:etiology; D013997:Time Factors; D016896:Treatment Outcome