title: Repeat radiosurgery for intracranial arteriovenous malformations.
abstract: BACKGROUND
  Despite a high success rate in the stereotactic radiosurgical treatment of intracranial arteriovenous malformations (AVMs) that cannot be safely resected with microsurgery, some patients must be managed after treatment failure.
  
  
  OBJECTIVE
  To provide an update on the use of repeat linear accelerator radiosurgery as a treatment for failed AVM radiosurgery at the University of Florida.
  
  
  METHODS
  We reviewed 103 patients who underwent repeat radiosurgical treatment for residual AVM at the University of Florida between December 1991 and December 2007. Each of these patients had at least 2 radiosurgical treatments for the same AVM. Patient information, including AVM nidus volume, prescription dose, age, and sex, was collected at the time of initial treatment and again at the time of retreatment. Patients were followed up after treatment with magnetic resonance, computed tomography, and angiographic imaging at standard intervals to determine the status of their AVM. The median follow-up after retreatment was 31 months.
  
  
  RESULTS
  Between the first and second treatments, the median AVM nidus volume was decreased by 69% (from a median volume of 12.7 to 4.0 cm), allowing the median prescribed dose to be increased from 1500 cGy on initial treatment to 1750 cGy on retreatment. The final obliteration rate on retreatment was 65.3%. After salvage retreatment, 5 patients (4.9%) experienced radiation-induced complications, and 6 patients (5.8%) experienced posttreatment hemorrhage.
  
  
  CONCLUSIONS
  Repeat radiosurgery is a safe and effective salvage treatment for AVMs.
authors: Department of Neurosurgery, University of Florida, Gainesville, Florida 32610, USA.
authors: John M
authors: JM
authors: Stahl
authors: Yueh-Yun
authors: YY
authors: Chi
authors: William A
authors: WA
authors: Friedman
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002533:Cerebral Angiography / Q000379:methods; D002648:Child; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D002538:Intracranial Arteriovenous Malformations / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D016634:Radiosurgery / Q000009:adverse effects*; D019233:Retreatment; D012189:Retrospective Studies; D017211:Treatment Failure; D016896:Treatment Outcome; D055815:Young Adult