title: Stereotactic Radiosurgery Treatment of Trigeminal Neuralgia: Clinical Outcomes and Prognostic Factors.
abstract: BACKGROUND
  Stereotactic radiosurgery (SRS) is a minimally invasive surgical option for the treatment of trigeminal neuralgia (TN). Here we review our institutional experience to identify prognostic factors associated with pain relief after SRS.
  
  
  METHODS
  263 patients with TN treated at the University of California, San Diego/San Diego Gamma Knife (2001-2013) were followed for more than 6 months. Univariate and multivariate Cox proportional hazard models analysis of factors associated with outcome was performed.
  
  
  RESULTS
  Of the 263 patients, 229 (87%) presented with classical idiopathic TN, 31 (12%) presented with atypical TN, and 4 (1%) presented with secondary TN. 143 (54%) had undergone prior treatment. Most patients were treated with 85 (52%) or 90 Gy (42%). 79% of the SRS treated patients experienced a favorable response (defined as Barrow Neurological Institute Pain Scale <3 pain relief), with a median time to relief of 2.5 months. In a multivariate analysis, diagnosis of classical TN, previous percutaneous procedures, and age older than 70 years were associated with favorable responses; classical TN was associated with sustained pain relief. Dose prescription >85 Gy and prior SRS were associated with bothersome facial numbness posttreatment. For patients presenting with classical TN, diagnosis of multiple sclerosis (MS) did not decrease the likelihood of pain relief after SRS.
  
  
  CONCLUSIONS
  Excellent TN pain relief was achieved with the delivery of 85 Gy in a single-shot, 4-mm isocenter SRS targeting the dorsal root entry zone. Patients with classical TN, with age older than 70 years, or who underwent previous percutaneous procedures were more likely to benefit from SRS. SRS is efficacious in patients with classical TN despite concurrent diagnosis of MS.
authors.affiliation: Department of Neurosurgery, Center for Translational and Applied Neuro-Oncology, University of California, San Diego, California, USA.
authors.forename: Zachary J
authors.initials: ZJ
authors.lastname: Taich
authors.affiliation: San Diego Gamma Knife Center, San Diego, California, USA.
authors.forename: Steven J
authors.initials: SJ
authors.lastname: Goetsch
authors.affiliation: San Diego Gamma Knife Center, San Diego, California, USA.
authors.forename: Elsa
authors.initials: E
authors.lastname: Monaco
authors.affiliation: Department of Neurosurgery, Center for Translational and Applied Neuro-Oncology, University of California, San Diego, California, USA.
authors.forename: Bob S
authors.initials: BS
authors.lastname: Carter
authors.affiliation: San Diego Gamma Knife Center, San Diego, California, USA.
authors.forename: Kenneth
authors.initials: K
authors.lastname: Ott
authors.affiliation: Department of Neurosurgery, Center for Translational and Applied Neuro-Oncology, University of California, San Diego, California, USA.
authors.forename: John F
authors.initials: JF
authors.lastname: Alksne
authors.affiliation: Department of Neurosurgery, Center for Translational and Applied Neuro-Oncology, University of California, San Diego, California, USA. Electronic address: clarkchen@ucsd.edu.
authors.forename: Clark C
authors.initials: CC
authors.lastname: Chen
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002140:California / Q000453:epidemiology; D015897:Comorbidity; D005157:Facial Pain / Q000453:epidemiology* / Q000517:prevention & control*; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D010147:Pain Measurement / Q000706:statistics & numerical data; D015995:Prevalence; D011379:Prognosis; D011832:Radiation Injuries / Q000453:epidemiology* / Q000517:prevention & control; D016634:Radiosurgery / Q000706:statistics & numerical data*; D012189:Retrospective Studies; D012307:Risk Factors; D016896:Treatment Outcome; D014277:Trigeminal Neuralgia / Q000453:epidemiology* / Q000532:radiotherapy*
keywords: Stereotactic radiosurgery; Trigeminal neuralgia