title: Subthalamic electrode implantation using the MicroDrive system and the importance of microrecording data.
abstract: OBJECTIVE
  The aim of the paper was to describe the relationship of the anatomical and electrophysiological target for the subthalamic electrode implantation in Parkinson's disease patients defined as the best electrophysiological recordings from multiple paralel electrodes tracts with a target discrepancy explanation.
  
  
  BACKGROUND
  Although microrecording is the standard in subthalamic stimulation, microelectrode monitoring prolongs surgical time and may increase the risk of haemorrhagic complications. The main purpose for the electrophysiological mapping is to overcome the discrepancy between the anatomical and electrophysiological targets.
  
  
  METHODS
  Subthalamic electrodes were stereotactically implanted in 58 patients using microrecording by means of parallel electrodes at defined distances. The relationship of the final electrode to the anatomical trajectory, the subthalamic nucleus electrical activity length, and the relationship of right and left electrodes were analysed.
  
  
  RESULTS
  The final electrode placement matched the anatomical trajectory in 53.4 % of patients on the right side, and 43.1 % of patients on the left side. The electrode position was symmetrical in 38.3 % of patients. The analysis of left and right electrode positions did not prove brain shift as the sole factor responsible for anatomy-functional discrepancy. Further, neither age, Parkinson's disease duration, or L-DOPA adverse effects were confirmed as responsible factors.
  
  
  CONCLUSIONS
  The difference between the anatomical trajectory and the final electrode placement underlined the need for functional microelectrode monitoring. Brain shift is not the only causative factor for the difference (Tab. 7, Ref. 27).
authors.affiliation: Department of neurosurgery MF MU FH St. Ann's Brno, Czech Republic. jan.chrastina@fnusa.cz
authors.forename: J
authors.initials: J
authors.lastname: Chrastina
authors.forename: Z
authors.initials: Z
authors.lastname: Novak
authors.forename: M
authors.initials: M
authors.lastname: Balaz
authors.forename: I
authors.initials: I
authors.lastname: Riha
authors.forename: M
authors.initials: M
authors.lastname: Bockova
mesh_terms: D000328:Adult; D000368:Aged; D046690:Deep Brain Stimulation / Q000295:instrumentation*; D004867:Equipment Design; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic; D010300:Parkinson Disease / Q000628:therapy*; D013788:Thalamus
keywords: stereotaxy, subthalamic stimulation, microelectrode recording, brain shift.