title: Transvenous to arterial Onyx embolization.
abstract: OBJECTIVE
  Transarterial infusion of Onyx is now widely used in the treatment of arteriovenous malformations (AVMs) and dural arteriovenous fistulas (DAVFs). Transvenous Onyx embolization is rarely performed, and usually in cases of carotid cavernous fistulas. We describe a novel technique of transvenous Onyx embolization in the treatment of three high risk DAVFs and one vein of Galen (VOG) AVM.
  
  
  METHODS
  Cases were evaluated with specific attention to technical caveats, clinical indications, and complications. Patients were treated during 2011-2012 by two operators (FCA and CGM). Standard transfemoral venous approaches were employed in order to obtain access into the draining venous system in all cases.
  
  
  RESULTS
  Four female patients, aged 5 months to 68 years, were treated. Two patients, one presenting with headache and the other with a bruit, demonstrated high risk DAVFs involving the transverse-sigmoid sinuses. One patient, who was asymptomatic, manifested a high risk ethmoidal DAVF that was discovered incidentally during treatment of a basilar aneurysm. The final patient presented with symptoms of a pineal region mass and was found to have a VOG AVM. In all cases, a microcatheter was navigated through the draining venous pouch and into the ostium of an arterial feeder. A single Onyx infusion from this position filled multiple arterial feeders and resulted in cures in the first three patients and a significant reduction in AVM nidus in the fourth patient. No complications occurred.
  
  
  CONCLUSIONS
  Transvenous Onyx infusion into a single arterial feeder can produce retrograde embolization of numerous other arterial feeders supplying high risk DAVFs and complex cerebral AVMs. This technique appears to be safe and potentially curative in select cases.
authors.affiliation: Division of Neurological Surgery, Barrow Neurological Institute, St Joseph's Hospital and Medical Center, Phoenix, Arizona, USA.
authors.forename: Felipe C
authors.initials: FC
authors.lastname: Albuquerque
authors.forename: Andrew F
authors.initials: AF
authors.lastname: Ducruet
authors.forename: R Webster
authors.initials: RW
authors.lastname: Crowley
authors.forename: Ruth E
authors.initials: RE
authors.lastname: Bristol
authors.forename: Azam
authors.initials: A
authors.lastname: Ahmed
authors.forename: Cameron G
authors.initials: CG
authors.lastname: McDougall
mesh_terms: D000368:Aged; D017536:Carotid Artery, Common / Q000002:abnormalities / Q000000981:diagnostic imaging; D002343:Carotid Artery, Internal / Q000002:abnormalities / Q000000981:diagnostic imaging; D020785:Central Nervous System Vascular Malformations / Q000000981:diagnostic imaging / Q000628:therapy*; D002533:Cerebral Angiography; D004621:Embolization, Therapeutic / Q000379:methods*; D005260:Female; D006801:Humans; D007223:Infant; D054080:Vein of Galen Malformations / Q000628:therapy
keywords: Liquid Embolic Material; Navigation; Technique; Vein