title: Multidisciplinary care of occipital arteriovenous malformations: effect on nonhemorrhagic headache, vision, and outcome in a series of 135 patients. Clinical article.
abstract: OBJECTIVE
  In this study, the authors evaluated how an appropriate allocation of patients with occipital arteriovenous malformations (AVMs) who were treated according to different strategies would affect nonhemorrhagic headache, visual function, and hemorrhage risk levels.
  
  
  METHODS
  Of the 712 patients with brain AVMs in the Toronto Western Hospital prospective database, 135 had occipital AVMs. The treatment decision was based on patients' characteristics, presentation, and morphology of the AVM. The management modalities were correlated with their outcomes.
  
  
  RESULTS
  The mean follow-up period was 6.78 years. Nonhemorrhagic headache was the most frequent symptom (82 [61%] of 135 patients). Ninety-four patients underwent treatment with one or a combination of embolization, surgery, or radiosurgery, and 41 were simply observed. Of the 40 nontreated patients with nonhemorrhagic headache, only 12 (30%) showed improvement. In the observation group 2 patients (22%) had worsening of visual symptoms, and 2 experienced hemorrhage, for an annual hemorrhage rate of 0.7% per year; 1 patient died. In the treatment group, the improvement in nonhemorrhagic headache in 35 patients (83%) was significant (p < 0.0001). Visual deficit at presentation worsened in 2 (8%), and there were 8 new visual field deficits (9%). The visual worsening was not significantly different. There were 2 other neurological deficits (2%) and 2 deaths (2%) related to the AVM treatment. One AVM hemorrhaged. The annual hemorrhage rate was 0.1% per year. The hemorrhage risk in the observation and treatment groups was lower than the observed hemorrhage risk of all patients with AVMs (4.6%) at the authors' institution.
  
  
  CONCLUSIONS
  Appropriate selection of patients with occipital AVMs for one or a combination of treatment modalities yields a significant decrease in nonhemorrhagic headache without significant visual worsening. The multidisciplinary care of occipital AVMs can aim for an apparent decrease in hemorrhage risk.
authors.affiliation: Division of Neurosurgery, Department of Medical Imaging, Toronto Western Hospital, University of Toronto, Ontario, Canada. ardehdashti@geisinger.edu
authors.forename: Amir R
authors.initials: AR
authors.lastname: Dehdashti
authors.forename: Laurent
authors.initials: L
authors.lastname: Thines
authors.forename: Robert A
authors.initials: RA
authors.lastname: Willinsky
authors.forename: Karel G
authors.initials: KG
authors.lastname: terBrugge
authors.forename: Michael L
authors.initials: ML
authors.lastname: Schwartz
authors.forename: Michael
authors.initials: M
authors.lastname: Tymianski
authors.forename: M Christopher
authors.initials: MC
authors.lastname: Wallace
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002543:Cerebral Hemorrhage / Q000209:etiology; D015331:Cohort Studies; D003131:Combined Modality Therapy; D004621:Embolization, Therapeutic; D005260:Female; D005500:Follow-Up Studies; D006261:Headache / Q000209:etiology / Q000628:therapy*; D006801:Humans; D002538:Intracranial Arteriovenous Malformations / Q000150:complications / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D009422:Nervous System Diseases / Q000628:therapy; D009778:Occipital Lobe / Q000473:pathology*; D016634:Radiosurgery; D016896:Treatment Outcome; D014786:Vision Disorders / Q000209:etiology / Q000628:therapy*; D055815:Young Adult