title: Stereotactic radiosurgery for cerebral arteriovenous malformations: evaluation of long-term outcomes in a multicenter cohort.
abstract: OBJECTIVE In this multicenter study, the authors reviewed the results following Gamma Knife radiosurgery (GKRS) of cerebral arteriovenous malformations (AVMs), determined predictors of outcome, and assessed predictive value of commonly used grading scales based upon this large cohort with long-term follow-up. METHODS Data from a cohort of 2236 patients undergoing GKRS for cerebral AVMs were compiled from the International Gamma Knife Research Foundation. Favorable outcome was defined as AVM obliteration and no posttreatment hemorrhage or permanent symptomatic radiation-induced complications. Patient and AVM characteristics were assessed to determine predictors of outcome, and commonly used grading scales were assessed. RESULTS The mean maximum AVM diameter was 2.3 cm, with a mean volume of 4.3 cm3. A mean margin dose of 20.5 Gy was delivered. Mean follow-up was 7 years (range 1-20 years). Overall obliteration was 64.7%. Post-GRKS hemorrhage occurred in 165 patients (annual risk 1.1%). Radiation-induced imaging changes occurred in 29.2%; 9.7% were symptomatic, and 2.7% had permanent deficits. Favorable outcome was achieved in 60.3% of patients. Patients with prior nidal embolization (OR 2.1, p < 0.001), prior AVM hemorrhage (OR 1.3, p = 0.007), eloquent location (OR 1.3, p = 0.029), higher volume (OR 1.01, p < 0.001), lower margin dose (OR 0.9, p < 0.001), and more isocenters (OR 1.1, p = 0.011) were more likely to have unfavorable outcomes in multivariate analysis. The Spetzler-Martin grade and radiosurgery-based AVM score predicted outcome, but the Virginia Radiosurgery AVM Scale provided the best assessment. CONCLUSIONS GKRS for cerebral AVMs achieves obliteration and avoids permanent complications in the majority of patients. Patient, AVM, and treatment parameters can be used to predict long-term outcomes following radiosurgery.
authors.affiliation: Department of Neurosurgery, University of Virginia, Charlottesville, Virginia.
authors.forename: Robert M
authors.initials: RM
authors.lastname: Starke
authors.affiliation: Department of Neurosurgery, University of Pittsburgh.
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Kano
authors.affiliation: Department of Neurosurgery, University of Virginia, Charlottesville, Virginia.
authors.forename: Dale
authors.initials: D
authors.lastname: Ding
authors.affiliation: Gamma Knife Center, University of Pennsylvania, Philadelphia, Pennsylvania.
authors.forename: John Y K
authors.initials: JY
authors.lastname: Lee
authors.affiliation: Department of Neurosurgery, University of Sherbrooke, Quebec, Canada.
authors.forename: David
authors.initials: D
authors.lastname: Mathieu
authors.affiliation: Gamma Knife Center, University of Pennsylvania, Philadelphia, Pennsylvania.
authors.forename: Jamie
authors.initials: J
authors.lastname: Whitesell
authors.affiliation: Gamma Knife Center, University of Pennsylvania, Philadelphia, Pennsylvania.
authors.forename: John T
authors.initials: JT
authors.lastname: Pierce
authors.affiliation: Gamma Knife Center, New York University, New York, New York.
authors.forename: Paul P
authors.initials: PP
authors.lastname: Huang
authors.affiliation: Gamma Knife Center, New York University, New York, New York.
authors.forename: Douglas
authors.initials: D
authors.lastname: Kondziolka
authors.affiliation: Department of Neurosurgery, University of Virginia, Charlottesville, Virginia.
authors.forename: Chun-Po
authors.initials: CP
authors.lastname: Yen
authors.affiliation: Department of Neurosurgery, University of Puerto Rico, San Juan, Puerto Rico.
authors.forename: Caleb
authors.initials: C
authors.lastname: Feliciano
authors.affiliation: Department of Neurosurgery, University of Puerto Rico, San Juan, Puerto Rico.
authors.forename: Rafael
authors.initials: R
authors.lastname: Rodgriguez-Mercado
authors.affiliation: Department of Neurosurgery, University of Puerto Rico, San Juan, Puerto Rico.
authors.forename: Luis
authors.initials: L
authors.lastname: Almodovar
authors.affiliation: Gamma Knife Center, Beaumont Health System, Royal Oak, Michigan; and.
authors.forename: Daniel R
authors.initials: DR
authors.lastname: Pieper
authors.affiliation: Gamma Knife Center, Beaumont Health System, Royal Oak, Michigan; and.
authors.forename: Inga S
authors.initials: IS
authors.lastname: Grills
authors.affiliation: Department of Neurosurgery, Cleveland Clinic Foundation, Cleveland, Ohio.
authors.forename: Danilo
authors.initials: D
authors.lastname: Silva
authors.affiliation: Department of Neurosurgery, Cleveland Clinic Foundation, Cleveland, Ohio.
authors.forename: Mahmoud
authors.initials: M
authors.lastname: Abbassy
authors.affiliation: Department of Neurosurgery, Cleveland Clinic Foundation, Cleveland, Ohio.
authors.forename: Symeon
authors.initials: S
authors.lastname: Missios
authors.affiliation: Department of Neurosurgery, Cleveland Clinic Foundation, Cleveland, Ohio.
authors.forename: Gene H
authors.initials: GH
authors.lastname: Barnett
authors.affiliation: Department of Neurosurgery, University of Pittsburgh.
authors.forename: L Dade
authors.initials: LD
authors.lastname: Lunsford
authors.affiliation: Department of Neurosurgery, University of Virginia, Charlottesville, Virginia.
authors.forename: Jason P
authors.initials: JP
authors.lastname: Sheehan
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D005260:Female; D006801:Humans; D002538:Intracranial Arteriovenous Malformations / Q000453:epidemiology / Q000532:radiotherapy*; D008297:Male; D008875:Middle Aged; D016634:Radiosurgery; D016896:Treatment Outcome; D055815:Young Adult
keywords: ARUBA = A Randomized Trial of Unruptured Brain AVMs; AUC = area under the receiver operating characteristic curve; AVM = arteriovenous malformation; GKRS = Gamma Knife radiosurgery; Gamma Knife; RBAS = radiosurgery-based AVM score (modified version); SAIVM = Scottish Audit of Intracranial Vascular Malformations; VRAS = Virginia Radiosurgery AVM Scale; arteriovenous malformation; complication; embolization; grading; hemorrhage; mHR = hazard ratio in the presence of mortality risk; outcome; radiation; scale; stereotactic radiosurgery; surgery; visual disorders