title: Cerebrospinal fluid levels of glial cell-derived neurotrophic factor correlate with spinal cord stimulation frequency in patients with neuropathic pain: a preliminary report.
abstract: METHODS
  Case series.
  
  
  OBJECTIVE
  To evaluate relationships between spinal cord stimulation (SCS) parameters and levels of glial cell-derived neurotrophic factor (GDNF).
  
  
  METHODS
  Ambulatory pain clinic of St James's Hospital, Dublin, Ireland.
  
  
  METHODS
  Nine patients with an implanted SCS and Failed Back Surgery Syndrome (FBSS) were administered the Brief Pain Inventory and Short Form (36) Health Survey. Following a lumbar puncture, levels of GDNF in cerebrospinal fluid (CSF) were assayed and correlated with stimulation parameters. Controls were patients with arthritic back pain who were matched for age, gender and SF-36 score.
  
  
  RESULTS
  Concentrations of GDNF in CSF are higher in patients with FBSS than controls (P=0.002) and correlate with SCS frequency (P=0.029).
  
  
  CONCLUSIONS
  Concentrations of GDNF in CSF are higher in neuropathic pain and appear to be related to stimulation frequency. Further work is needed to evaluate this potential relationship, both in neuropathic pain and in other contexts such as locomotor dysfunction.
authors.affiliation: 1] Department of Physiology, Trinity College Dublin, Dublin, Ireland [2] Department of Pain Medicine, St. James's Hospital, Dublin, Ireland.
authors.forename: K F
authors.initials: KF
authors.lastname: McCarthy
authors.affiliation: Department of Pain Medicine, St. James's Hospital, Dublin, Ireland.
authors.forename: C
authors.initials: C
authors.lastname: McCrory
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D051100:Glial Cell Line-Derived Neurotrophic Factor / Q000134:cerebrospinal fluid*; D006801:Humans; D007118:Immunoassay; D058542:Implantable Neurostimulators; D008163:Luminescent Measurements; D008297:Male; D008875:Middle Aged; D009437:Neuralgia / Q000134:cerebrospinal fluid* / Q000628:therapy*; D062187:Spinal Cord Stimulation / Q000379:methods*; D013129:Spinal Puncture
chemical_list: C495039:GDNF protein, human; D051100:Glial Cell Line-Derived Neurotrophic Factor