title: [Automatic classification of liver segments according to Couinaud: development of a new algorithm and evaluation spiral CT data].
abstract: OBJECTIVE
  To develop a software tool that analyzes the anatomy of the portal vein branches and assigns segmental and subsegmental branches according to Couinaud's classification system and to evaluate its accuracy.
  
  
  METHODS
  The algorithm was developed in C++ on a PC. The algorithm recognizes the three major branching patterns of the portal vein. Segmental and subsegmental branches are assigned to 8 segments following Couinaud and encoded by 8 colors. The software was evaluated using CT data sets of 39 patients. After the individual segmental anatomy of each patient was determined by an experienced radiologist, automatic classification was performed and the results were compared on a branch by branch basis.
  
  
  RESULTS
  The numbering was accurate according to Couinaud's system in 358 of 409 segmental and subsegmental branches (88 %). The assignment failed in 51 of 409 branches due to unexpected anatomy or software problems.
  
  
  CONCLUSIONS
  Automatic classification of portal vein branches and their appendant parenchyma is possible. The automatic designation of liver segments enables the three-dimensional visualization of the segmental anatomy. In the future, automatic analysis might facilitate the reporting and communication of CT findings.
authors.affiliation: Klinik für Radiologie der Johannes-Gutenberg-Universität Mainz. rieker@radiologie.klinik.uni-mainz.de
authors.forename: O
authors.initials: O
authors.lastname: Rieker
authors.forename: G
authors.initials: G
authors.lastname: Klos
authors.forename: P
authors.initials: P
authors.lastname: Beckmann
authors.forename: T W
authors.initials: TW
authors.lastname: Vomweg
authors.forename: G
authors.initials: G
authors.lastname: Otto
authors.forename: M
authors.initials: M
authors.lastname: Thelen
mesh_terms: D000465:Algorithms; D002965:Classification; D006801:Humans; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional; D008099:Liver / Q000033:anatomy & histology* / Q000000981:diagnostic imaging* / Q000601:surgery; D011169:Portal Vein / Q000033:anatomy & histology* / Q000000981:diagnostic imaging* / Q000601:surgery; D012984:Software; D036542:Tomography, Spiral Computed