title: Fistula component of cerebral arteriovenous malformations: morphologic change after stereotactic radiosurgery and outcome of embolisation.
abstract: BACKGROUND
  The angioarchitecture of arteriovenous fistulas (AVFs) of cerebral arteriovenous malformation (CAVM) after stereotactic radiosurgery (SRS) remain unclear. The purpose of this study is to report the angiographic change of AVF components of CAVMs after SRS and outcomes of endovascular embolisation.
  
  
  METHODS
  From 2002 to 2012, a total of 523 CAVMs had been treated primarily by SRS with more than 3-year latency. Among these databases, there were 19 patients with 21 AVFs undergoing embolization after SRS. We retrospectively analyzed the angioarchitecture of the CAVM to identify AVFs, morphologic change and outcomes of AVFs after SRS and embolisation.
  
  
  RESULTS
  Eight AVFs were in the periphery of CAVMs, the other 13 were in a central location. Eighteen of 21 AVFs remained constant in morphology after SRS, while three feeders of AVFs were associated with radiation arteritis. The causes of failure to identify AVFs before SRS were overlooked (n = 7) or there was superimposition with feeders, nidus and/or venous drains of CAVMs (n = 14). Total fistula occlusion was achieved in all 21 AVFs; residual CAVMs was totally obliterated by embolisation and/or additional SRS in 12 patients. One patient had a small procedure-related intracerebral hemorrhage. Mean follow-up period was 26 months.
  
  
  CONCLUSIONS
  Early detection of AVF components of CAVMs prior to SRS may be difficult, particularly those in a central location. However, most AVFs became evident and showed consistency in angiographic morphology after obliteration of the majority nidus parts of CAVMs. Endovascular embolisation is effective in managing these AVF components.
authors.affiliation: Department of Radiology, Taipei Veterans General Hospital, 201, Section 2, Shih-Pai Road, Taipei 112, Taiwan, Republic of China, cbluo@vghtpe.gov.tw.
authors.forename: Chao-Bao
authors.initials: CB
authors.lastname: Luo
authors.forename: Wan-Yuo
authors.initials: WY
authors.lastname: Guo
authors.forename: Feng-Chi
authors.initials: FC
authors.lastname: Chang
authors.forename: Hsiu-Mei
authors.initials: HM
authors.lastname: Wu
authors.forename: Michael M H
authors.initials: MM
authors.lastname: Teng
authors.forename: Chung-Jung
authors.initials: CJ
authors.lastname: Lin
authors.forename: David H C
authors.initials: DH
authors.lastname: Pan
authors.forename: Wen-Yuh
authors.initials: WY
authors.lastname: Chung
authors.forename: Cheng-Yen
authors.initials: CY
authors.lastname: Chang
mesh_terms: D000328:Adult; D000368:Aged; D001164:Arteriovenous Fistula / Q000453:epidemiology / Q000473:pathology / Q000628:therapy*; D002533:Cerebral Angiography / Q000379:methods; D002543:Cerebral Hemorrhage / Q000473:pathology / Q000532:radiotherapy / Q000601:surgery*; D004621:Embolization, Therapeutic / Q000379:methods; D005260:Female; D006801:Humans; D002538:Intracranial Arteriovenous Malformations / Q000473:pathology / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D016896:Treatment Outcome