title: Late clinical and radiological complications of stereotactical radiosurgery of arteriovenous malformations of the brain.
abstract: BACKGROUND
  Post-radiation injury of patients with brain arteriovenous malformations (AVM) include blood-brain barrier breakdown (BBBB), edema, and necrosis. Prevalence, clinical relevance, and response to treatment are poorly known. We present a series of consecutive brain AVM treated with stereotactic radiosurgery describing the appearance of radiation injury and clinical complications.
  
  
  METHODS
  Consecutive patients with annual clinical and radiological follow-up (median length 63 months). Edema and BBBB were classified in four groups (minimal, perilesional, moderate, or severe), and noted together with necrosis. Clinical symptoms of interest were intracranial hypertension, new neurological deficits, new seizures, and brain hemorrhages.
  
  
  RESULTS
  One hundred two cases, median age 34 years, 52% male. Median irradiated volume 3.8 cc, dose to the margin of the nidus 18.5 Gy. Nineteen patients underwent a second radiosurgery. Only 42.2% patients remained free from radiation injury. Edema was found in 43.1%, blood-brain barrier breakdown in 20.6%, necrosis in 6.9%. Major injury (moderate or severe edema, moderate or severe BBBB, or necrosis) was found in 20 of 102 patients (19.6%). AVM diameter >3 cm and second radiosurgery were independent predictors. Time to the worst imaging was 60 months. Patients with major radiation injury had a hazard ratio for appearance of focal deficits of 7.042 (p = 0.04), of intracranial hypertension 2.857 (p = 0.025), hemorrhage into occluded nidus 9.009 (p = 0.079), appearance of new seizures not significant.
  
  
  CONCLUSIONS
  Major radiation injury is frequent and increases the risk of neurological complications. Its late appearance implies that current follow-up protocols need to be extended in time.
authors.affiliation: Department of Neurology, Hospital Universitario la Fe, Valencia, Spain. parkhutik_ver@yahoo.com
authors.forename: Vera
authors.initials: V
authors.lastname: Parkhutik
authors.forename: Aida
authors.initials: A
authors.lastname: Lago
authors.forename: Fernando
authors.initials: F
authors.lastname: Aparici
authors.forename: Juan Francisco
authors.initials: JF
authors.lastname: Vazquez
authors.forename: Jose Ignacio
authors.initials: JI
authors.lastname: Tembl
authors.forename: Lourdes
authors.initials: L
authors.lastname: Guillen
authors.forename: Esperanza
authors.initials: E
authors.lastname: Mainar
authors.forename: Victor
authors.initials: V
authors.lastname: Vazquez
mesh_terms: D000293:Adolescent; D000328:Adult; D001929:Brain Edema / Q000209:etiology* / Q000473:pathology*; D002648:Child; D005260:Female; D006801:Humans; D002538:Intracranial Arteriovenous Malformations / Q000150:complications / Q000175:diagnosis / Q000601:surgery*; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D011832:Radiation Injuries / Q000209:etiology* / Q000473:pathology*; D016634:Radiosurgery / Q000009:adverse effects*; D016896:Treatment Outcome; D055815:Young Adult