title: Usefulness of neurophysiologic techniques in stereotactic subthalamic nucleus stimulation for advanced Parkinson's disease.
abstract: OBJECTIVE
  The objectives of this study are to determine the impact of neurophysiologic guidance on subthalamic nucleus (STN) targeting and to assess its safety and effectiveness.
  
  
  METHODS
  We have compared the initial theoretic anatomic target (TAT) of the STN with the final microrecording guided coordinates in 15 consecutive patients with bilaterally implanted electrodes in the STN. The clinical results and adverse effects are also reported. All comparisons were done through a paired Student's t test and Pearson's correlation test.
  
  
  RESULTS
  Neurophysiological guidance changed the target coordinates in 26 of the procedures. The mean correction applied to the TAT in order to place the electrode in its definite location was 0.4 mm (+/-0.8, range 0-3; P=0.03) in the medial-lateral axis, 1.6 mm (+/-1.2, range 0-5; P=0.01) in the anterior-posterior plane and 0.8 mm (+/-0.8, range 0-3; P=0.26) in the vertical axis. The mean number of microrecording tracks employed to localize each STN was 2.8+/-1.8 (range 1-8) tracks. After surgery, the total UPDRS motor score in the off medication condition improved by 65.9%; UPDRS-II scores were reduced by 71.8% and Schwab and England scores improved by 45.3%. No intraoperative hemorrhages occurred in this series.
  
  
  CONCLUSIONS
  Neurophysiological guidance is a safe and useful tool in order to improve and confirm target localization. The correction applied in the target resulted in a significant clinical improvement 6 months after surgery.
mesh_terms: D000368:Aged; D001931:Brain Mapping; D004558:Electric Stimulation / Q000379:methods; D004599:Electric Stimulation Therapy; D004567:Electrodes, Implanted; D004594:Electrophysiology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008839:Microelectrodes; D008875:Middle Aged; D010300:Parkinson Disease / Q000503:physiopathology / Q000601:surgery* / Q000628:therapy; D015203:Reproducibility of Results; D013238:Stereotaxic Techniques; D020531:Subthalamic Nucleus / Q000503:physiopathology / Q000601:surgery*; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome