title: Surgery for Unruptured Spetzler-Martin Grade 3 Brain Arteriovenous Malformations: A Prospective Surgical Cohort.
abstract: BACKGROUND
  There is uncertainty regarding the management of unruptured Spetzler-Martin grade 3 brain arteriovenous malformations (SMG3 ubAVM).
  
  
  OBJECTIVE
  To analyze our series of patients treated by surgery.
  
  
  METHODS
  A single-surgeon database of consecutively enrolled bAVMs (between 1989 and 2014) was analyzed. Adverse outcomes due to surgery were assigned within the first 6 weeks following surgery and outcome was prospectively recorded and assigned at the last follow-up visit by using modified Rankin Scale (mRS) score.
  
  
  RESULTS
  Of the 137 reviewed patients, 112 (82%) were treated by surgery, 15 (11%) were treated elsewhere or by radiosurgery, and 10 (7%) were recommended for conservative management. Surgery for SMG3 ubAVM was associated with adverse outcomes with a new permanent neurological deficit of mRS >1 in 23 of 112 (21%) patients. Permanent neurological deficit leading to a mRS >2 from surgery was 3.6% (95% confidence interval, 1.1%-9.1%). Late recurrence of a bAVM occurred in 3 of 103 (2.9%) patients who had complete obliteration of bAVM confirmed immediately after surgery and who were subsequently later followed with radiological studies during the mean follow-up period of 3.0 years (range, 6 days to 18.8 years).
  
  
  CONCLUSIONS
  When discussing surgical options for SMG3 ubAVM, a thorough understanding of the significance and incidence of adverse events and outcomes is required to fully inform patients. For our series, the additional subclassification of SMG ubAVM (based on variables contributing to the SMG or age) would not have been of use.
authors: *Australian School of Advanced Medicine, Macquarie University, Sydney, NSW, Australia; ‡Department of Neurosurgery, Helsinki University Central Hospital, Helsinki, Finland.
authors: Michael Kerin
authors: MK
authors: Morgan
authors: Nazih
authors: N
authors: Assaad
authors: Miikka
authors: M
authors: Korja
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001921:Brain / Q000601:surgery*; D002648:Child; D002675:Child, Preschool; D004621:Embolization, Therapeutic / Q000379:methods*; D005260:Female; D006801:Humans; D002538:Intracranial Arteriovenous Malformations / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D016634:Radiosurgery / Q000379:methods*; D012008:Recurrence; D016896:Treatment Outcome; D055815:Young Adult