title: The use of time-of-flight camera for navigating robots in computer-aided surgery: monitoring the soft tissue envelope of minimally invasive hip approach in a cadaver study.
abstract: BACKGROUND
  Time-of-flight (TOF) cameras can guide surgical robots or provide soft tissue information for augmented reality in the medical field. In this study, a method to automatically track the soft tissue envelope of a minimally invasive hip approach in a cadaver study is described.
  
  
  METHODS
  An algorithm for the TOF camera was developed and 30 measurements on 8 surgical situs (direct anterior approach) were carried out. The results were compared to a manual measurement of the soft tissue envelope.
  
  
  RESULTS
  The TOF camera showed an overall recognition rate of the soft tissue envelope of 75%. On comparing the results from the algorithm with the manual measurements, a significant difference was found (P > .005).
  
  
  CONCLUSIONS
  In this preliminary study, we have presented a method for automatically recognizing the soft tissue envelope of the surgical field in a real-time application. Further improvements could result in a robotic navigation device for minimally invasive hip surgery.
authors.affiliation: Innsbruck Medical University, Innsbruck, Austria david.putzer@i-med.ac.at.
authors.forename: David
authors.initials: D
authors.lastname: Putzer
authors.affiliation: Innsbruck Medical University, Innsbruck, Austria.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Klug
authors.affiliation: Stryker IMT, Freiburg, Germany.
authors.forename: Jose Luis
authors.initials: JL
authors.lastname: Moctezuma
authors.affiliation: Innsbruck Medical University, Innsbruck, Austria.
authors.forename: Michael
authors.initials: M
authors.lastname: Nogler
mesh_terms: D019644:Arthroplasty, Replacement, Hip / Q000295:instrumentation* / Q000379:methods*; D006615:Hip / Q000601:surgery; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000295:instrumentation*; D065287:Robotic Surgical Procedures / Q000295:instrumentation*; D025321:Surgery, Computer-Assisted / Q000295:instrumentation*
keywords: computer-aided surgery; minimally invasive hip arthroplasty; robotic navigation; soft tissue envelope; soft tissue motion tracking