title: Transvenous hemodynamic assessment of arteriovenous malformations and fistulas. Preliminary clinical experience in Doppler guidewire monitoring of embolotherapy.
abstract: OBJECTIVE
  Transvenous monitoring of blood flow through intracranial vascular malformations was performed with an intravascular Doppler guidewire to assess hemodynamic changes during endovascular embolotherapy.
  
  
  METHODS
  Flow velocity was assessed in the intracranial venous sinuses of two patients with arteriovenous malformations and seven patients with dural arteriovenous fistulas. In all cases, the Doppler guidewire was positioned in the dural sinuses coaxially through a 2.1F microcatheter. The Doppler guidewire was then advanced to the site of arteriovenous shunting for sampling of venous average peak velocity (APV) and pulsatility index. In two cases, simultaneous feeding artery flow velocity was monitored by transcranial color-coded duplex sonography.
  
  
  RESULTS
  Before embolotherapy, the flow pattern in the venous sinuses was pulsatile, with a mean (+/-SD) APV of 39.0 +/- 22.5 cm/s. Total or near-total embolization was achieved in six of the nine cases. After embolization, the flow pattern became less pulsatile and the APV was reduced to a mean of 21.2 +/- 14.6 cm/s (P = .0123, one-tailed paired t test). The pulsatility index was used to calculate the maximum minus the minimum peak velocity (MxPV-MnPV). This was reduced from an average of 27.0 +/- 8.7 cm/s to 13.5 +/- 8.3 cm/s after treatment (P = .0456). A parallel reduction in APV of the feeding arteries was observed with embolization.
  
  
  CONCLUSIONS
  Preliminary clinical experience indicates that transvenous assessment of two parameters, APV and MxPV-MnPV, is useful in the hemodynamic evaluation of intracranial arteriovenous shunts. This valuable hemodynamic information may be used for objective and quantitative monitoring during embolotherapy of intracranial vascular malformations.
authors.affiliation: Department of Neurosurgery, Jikei University School of Medicine, Tokyo, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Murayama
authors.forename: S
authors.initials: S
authors.lastname: Usami
authors.forename: Y
authors.initials: Y
authors.lastname: Hata
authors.forename: F
authors.initials: F
authors.lastname: Ganaha
authors.forename: Y
authors.initials: Y
authors.lastname: Hasegawa
authors.forename: T
authors.initials: T
authors.lastname: Terao
authors.forename: S
authors.initials: S
authors.lastname: Abe
authors.forename: H
authors.initials: H
authors.lastname: Furuhata
authors.forename: T
authors.initials: T
authors.lastname: Abe
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000792:Angiography; D001164:Arteriovenous Fistula / Q000000981:diagnostic imaging* / Q000628:therapy; D001165:Arteriovenous Malformations / Q000000981:diagnostic imaging* / Q000628:therapy; D002560:Cerebrovascular Circulation / Q000502:physiology; D004621:Embolization, Therapeutic; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic; D011673:Pulsatile Flow / Q000502:physiology; D014463:Ultrasonography