title: Embolization of cerebral arteriovenous malformations achieved with polyvinyl alcohol particles: angiographic reappearance and complications.
abstract: OBJECTIVE
  The appropriate choice of embolic materials with respect to the permanency of obliterated nidi after embolization and complications related to the procedure is essential for safe and effective embolization of cerebral arteriovenous malformations (AVMs). Our purpose was to ascertain the recanalization and complication rates after AVM treatment with polyvinyl alcohol (PVA) particles.
  
  
  METHODS
  Between 1988 and 1994, 36 AVMs were embolized with PVA particles at our institution. Follow-up angiographic findings and occurrence of complications during the embolization procedures were analyzed retrospectively.
  
  
  RESULTS
  Complete obliteration of the nidus immediately after embolization was achieved in five patients, and 80% to 99% obliteration was attained in 12 patients. Fifty-one follow-up angiographic examinations were performed 1 week to 60 months (mean, 7 months) after embolization in 31 patients. An increase in nidal size was seen on 15 follow-up angiograms (29%) and a decrease was seen in seven (14%). In 28 of the 51 angiograms obtained more than 1 month after follow up (mean, 13 months), 12 (43%) showed AVM enlargement. In four (80%) of five cases of complete obliteration, nidi reappeared on follow-up angiograms. Hemorrhagic complications occurred in three cases and ischemic ones in seven. One patient (3%) died and five (14%) suffered persistent neurologic deficits.
  
  
  CONCLUSIONS
  Embolization with PVA particles can produce significant volume reduction in AVM nidal size, but recanalization is a distinct possibility.
authors.affiliation: Department of Neurosurgery, Brain Research Institute, Niigata University, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Sorimachi
authors.forename: T
authors.initials: T
authors.lastname: Koike
authors.forename: S
authors.initials: S
authors.lastname: Takeuchi
authors.forename: T
authors.initials: T
authors.lastname: Minakawa
authors.forename: H
authors.initials: H
authors.lastname: Abe
authors.forename: K
authors.initials: K
authors.lastname: Nishimaki
authors.forename: Y
authors.initials: Y
authors.lastname: Ito
authors.forename: R
authors.initials: R
authors.lastname: Tanaka
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002533:Cerebral Angiography; D004621:Embolization, Therapeutic / Q000009:adverse effects; D005260:Female; D006801:Humans; D002538:Intracranial Arteriovenous Malformations / Q000000981:diagnostic imaging / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D011142:Polyvinyl Alcohol / Q000008:administration & dosage*; D015641:Radiography, Interventional; D012008:Recurrence; D012189:Retrospective Studies
chemical_list: D011142:Polyvinyl Alcohol