title: [Basilar artery occlusion with benign outcome--two case reports and a review on the role of collateral circulation and therapeutic time window].
abstract: We reported two cases of acute basilar artery occlusion (BAO) with favorable prognosis and discussed the role of collateral circulation. Patient 1 presented with minor brainstem dysfunction for 24 hours due to a short-segment embolic BAO at the mid-pontine level. Carotid angiogram demonstrated reversed basilar flow through the posterior communicating artery distal to the occlusion. Subsequently, the patient suddenly went into coma and developed tetraplegia due to spontaneous displacement and lodging of the embolus to the top of the basilar artery. Immediate recanalization was achieved by intra-arterial thrombolysis, and she recovered and was independent at 3 months after onset. Patient 2 developed progressive brainstem and cerebellar dysfunction due to thrombotic occlusion of the intracranial vertebral and the proximal basilar artery. Angiographic studies demonstrated that reversed basilar flow from the carotid system and meningeal anastomosis arising from the proximal vertebral artery filled the basilar artery distal to the occlusion. The patient recovered after conservative treatment leaving only residual signs of lateral medullary infarction. Recent case series show varied prognosis of BAO. Individual differences in the effectiveness of collateral circulation may be one of the reasons that accounts for this variability. The interval of reversible brainstem ischemia supported by the collaterals may widen the therapeutic time window up to recanalization following acute basilar artery occlusion.
authors.affiliation: Department of Neurology, Tokyo Rosai Occupational Diseases and Injuries Hospital, Ohta-ku, Tokyo, Japan.
authors.forename: Hideki
authors.initials: H
authors.lastname: Ohno
authors.forename: Masashi
authors.initials: M
authors.lastname: Nakajima
authors.forename: Ryuta
authors.initials: R
authors.lastname: Fukuya
authors.forename: Shinsuke
authors.initials: S
authors.lastname: Fujioka
authors.forename: Kohnosuke
authors.initials: K
authors.lastname: Iwamoto
authors.forename: Shigeru
authors.initials: S
authors.lastname: Kadoyama
authors.forename: Takayuki
authors.initials: T
authors.lastname: Tachizawa
authors.forename: Kazuaki
authors.initials: K
authors.lastname: Sugiura
mesh_terms: D000208:Acute Disease; D000368:Aged; D000925:Anticoagulants / Q000008:administration & dosage*; D003097:Collateral Circulation / Q000502:physiology*; D003952:Diagnostic Imaging; D005260:Female; D006493:Heparin / Q000008:administration & dosage; D006801:Humans; D007261:Infusions, Intra-Arterial; D008297:Male; D015912:Thrombolytic Therapy; D013997:Time Factors; D016896:Treatment Outcome; D014568:Urokinase-Type Plasminogen Activator / Q000008:administration & dosage; D014715:Vertebrobasilar Insufficiency / Q000175:diagnosis / Q000628:therapy*; D014859:Warfarin / Q000008:administration & dosage
chemical_list: D000925:Anticoagulants; D014859:Warfarin; D006493:Heparin; D014568:Urokinase-Type Plasminogen Activator