title: The anatomical and electrophysiological subthalamic nucleus visualized by 3-T magnetic resonance imaging.
abstract: BACKGROUND
  Accurate localization of the subthalamic nucleus (STN) is critical to the success of deep brain stimulation surgery for Parkinson disease. Recent developments in high-field-strength magnetic resonance imaging (MRI) have made it possible to visualize the STN in greater detail. However, the relationship of the MR-visualized STN to the anatomic, electrophysiological, or atlas-predicted STN remains controversial.
  
  
  OBJECTIVE
  To evaluate the size of the STN visualized on 3-T MRI compared with anatomic measurements in cadaver studies and to compare the predictions of 3-T MRI and those of the Schaltenbrand-Wahren (SW) atlas for intraoperative STN microelectrode recordings.
  
  
  METHODS
  We evaluated the STN by 3-T MRI and intraoperative microelectrode recordings in 20 Parkinson disease patients undergoing deep brain stimulation surgery. We compared our findings with anatomic cadaver studies and with the individually scaled SW atlas-based predictions for each patient.
  
  
  RESULTS
  The dimensions of the 3-T MR-visualized STN were very similar to those of the largest anatomic study (MRI length, width, and height: 9.8 ± 1.6, 11.5 ± 1.6, and 3.7 ± 0.7 mm, respectively; n = 40; cadaver length, width, and height: 9.3 ± 0.7, 10.6 ± 0.9, and 3.1 ± 0.5 mm, respectively; n = 100). The amount of STN traversed during intraoperative microelectrode recordings was better correlated to the 3-T MR-visualized STN than the SW atlas-predicted STN (R = 0.38 vs R = -0.17).
  
  
  CONCLUSIONS
  The STN as visualized on 3-T MRI corresponds well with cadaveric anatomic studies and intraoperative electrophysiology. STN visualization with 3-T MRI may be an improvement over SW atlas-based localization for STN deep brain stimulation surgery in Parkinson disease.
authors.affiliation: Surgical Therapies Improving Movement Program, University of Michigan Health System, Ann Arbor, Michigan 48109-5338, USA. pgpatil@umich.edu
authors.forename: Parag G
authors.initials: PG
authors.lastname: Patil
authors.forename: Erin C
authors.initials: EC
authors.lastname: Conrad
authors.forename: J Wayne
authors.initials: JW
authors.lastname: Aldridge
authors.forename: Thomas L
authors.initials: TL
authors.lastname: Chenevert
authors.forename: Kelvin L
authors.initials: KL
authors.lastname: Chou
mesh_terms: D000368:Aged; D002102:Cadaver; D046690:Deep Brain Stimulation / Q000379:methods*; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000473:pathology / Q000503:physiopathology / Q000628:therapy; D013223:Statistics as Topic; D020531:Subthalamic Nucleus / Q000473:pathology* / Q000502:physiology*