title: Stereotactic localization and visualization of the subthalamic nucleus.
abstract: BACKGROUND
  The subthalamic nucleus (STN) is widely recognized as one of the most important and commonly targeted nuclei in stereotactic and functional neurosurgery. The success of STN surgery depends on accuracy in target determination. Construction of a digitalized atlas of STN based on stereotactic MRI will play an instrumental role in the accuracy of anatomical localization. The aim of this study was to investigate the three-dimensional (3D) target location of STN in stereotactic space and construct a digitalized atlas of STN to accomplish the visualization of the STN on stereotactic MRI, thus providing clinical guidance on the precise anatomical localization of STN.
  
  
  METHODS
  One hundred and twenty healthy people volunteered to be scanned by 1.5 Tesla MRI scanning with 1-mm-thick slice in the standard stereotactic space between 2005 and 2006. One adult male was selected for 3D reconstruction of STN. The process of 3D reconstruction included identification, manual segmentation, extraction, conservation and reconstruction.
  
  
  RESULTS
  There was a significant correlation between the coordinates and age (P < 0.05). The volume of left STN was significantly larger than the right STN, and there was a significant negative correlation between volume and age (P < 0.05). The surface of the STN nucleus after 3D reconstruction appeared smooth, natural and realistic. The morphological feature of STN on the individual brain could be visualized directly in 3D. The 3D reconstructed STN could be rotated, zoomed and displayed at any direction in the stereotactic space. The anteroposterior diameter of the STN nucleus was longer than the vertical and transverse diameters in 3D space. The 3D reconstruction of STN manifested typical structure of the "dual lens".
  
  
  CONCLUSIONS
  The visualization of individual brain atlas based on stereotactic MRI is feasible. However, software for automated segmentation, extraction and registration of MR images need to be further developed.
authors.affiliation: Department of Neurosurgery, First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150001, China.
authors.forename: Wei-gao
authors.initials: WG
authors.lastname: Shen
authors.forename: Hai-yang
authors.initials: HY
authors.lastname: Wang
authors.forename: Zhi-guo
authors.initials: ZG
authors.lastname: Lin
authors.forename: Hong
authors.initials: H
authors.lastname: Shen
authors.forename: Xiao-guang
authors.initials: XG
authors.lastname: Chen
authors.forename: Yi-li
authors.initials: YL
authors.lastname: Fu
authors.forename: Wen-peng
authors.initials: WP
authors.lastname: Gao
mesh_terms: D000328:Adult; D000368:Aged; D001921:Brain / Q000033:anatomy & histology; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D020531:Subthalamic Nucleus / Q000033:anatomy & histology*; D055815:Young Adult