title: Peripheral Nerve Stimulation for the Treatment of Chronic Intractable Headaches: Long-term Efficacy and Safety Study.
abstract: BACKGROUND
  Despite the various modalities available for treating headaches, typical therapy does not provide adequate pain relief for some patients.
  
  
  OBJECTIVE
  This study explored the efficacy and safety of long-term peripheral nerve stimulation (PNS) for intractable chronic headaches.
  
  
  METHODS
  Retrospective study of refractory headache patients at academic pain center.
  
  
  METHODS
  The medical records of all patients (N = 46) permanently implanted with PNS between January 2005 and January 2012 were reviewed retrospectively. Patient records and phone interviews were used to quantify the levels of pain intensity, headache days per month, and overall patient satisfaction with treatment. The correlation between headache duration and effectiveness of PNS was also assessed.
  
  
  RESULTS
  Pain intensity on the 11-point Numeric Rating Scale decreased from 7.60 ± 1.73 before implantation to 3.78 ± 2.41, 3.32 ± 2.67, 3.42 ± 2.74, and 2.04 ± 2.27 at one, 6, 12, and > 12 (19-98) months after implantation, respectively (P < .001). The mean number of headache days per month decreased by about 14 days from the base line. No correlation (r = -.33) was found between the number of years the patients had suffered from headaches and the efficacy of treatment.
  
  
  CONCLUSIONS
  Due to the limitation of a retrospective study, the data collected via chart reviews and phone interviews are susceptible to selection and information biases.
  
  
  CONCLUSIONS
  PNS is an effective modality in the long-term management of intractable chronic headaches. Despite long histories of chronic headaches, the majority of patients had significant reductions in pain scores and the number of headache days per month. The outcomes were not dependent on the number of years the patients had suffered from headaches before PNS treatment.
authors.affiliation: Department of Anesthesiology and Pain Medicine, Seoul National University Bundang Hospital, Seongnam, Korea.
authors.forename: Pyung B
authors.initials: PB
authors.lastname: Lee
authors.affiliation: Department of Anesthesiology, Duke University Medical Center, Durham, NC.
authors.forename: Christian
authors.initials: C
authors.lastname: Horazeck
authors.affiliation: Department of Anesthesiology and Pain Medicine, Seoul National University Bundang Hospital, Seongnam, South Korea.
authors.forename: Francis S
authors.initials: FS
authors.lastname: Nahm
authors.forename: Billy K
authors.initials: BK
authors.lastname: Huh
mesh_terms: D000328:Adult; D000368:Aged; D004599:Electric Stimulation Therapy / Q000379:methods*; D004567:Electrodes, Implanted; D005260:Female; D020773:Headache Disorders / Q000628:therapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D018710:Pain Clinics; D010147:Pain Measurement; D010148:Intractable Pain / Q000628:therapy*; D017060:Patient Satisfaction; D010525:Peripheral Nerves; D012189:Retrospective Studies; D004561:Transcutaneous Electric Nerve Stimulation; D016896:Treatment Outcome