title: Adding the third dimension--a new tool for constructing 3D models of the airway from 2D bronchoscopic video.
abstract: OBJECTIVE
  To develop a new method of using existing bronchoscopic video technology to generate a 3D model of the airway for clinical purposes.
  
  
  METHODS
  Prospective pilot study with clinical correlation.
  
  
  METHODS
  A Storz 7200 bronchoscope was used to obtain video of a standardized tube. The images were then processed using "open source" tools which detected feature points. A three dimensional model was then constructed using these feature points. An in-house 3D image program was then used to compare the 3D model with the standardized tube. Video from a representative airway patient who had previously had a CT of the chest and a bronchoscopic examination was also analyzed using this technique. The 3D model was correlated with CT images to clinically validate this technique.
  
  
  METHODS
  Tertiary care hospital.
  
  
  METHODS
  One airway patient video was used for clinical validation.
  
  
  METHODS
  (1) Average diameters of the 3D video derived tube model were compared to the actual tube and (2) a cross section of the 3D video derived patient model was compared to the patient CT derived model.
  
  
  RESULTS
  Repeated measures on standardized tubes demonstrated that is it possible to construct an airway model using this novel technique with a less than 5% error. Further, it is possible to construct a 3D model from patient video using existing bronchoscopic technology.
  
  
  CONCLUSIONS
  It is possible to extract 3D data from a sequence of 2D images. Further, this 3D model can be used for the purposes of management and planning and is quantitatively accurate and reliable. Initial data suggests that these measurements correlate with actual airway size and may provide a better instrument with which to make surgical decisions.
authors.affiliation: Department of Pediatric Otolaryngology, Cincinnati Children's Hospital Medical Center, 3333 Burnet Avenue, Cincinnati, OH 45208, USA. matthew.bromwich@cchmc.org
authors.forename: Matthew
authors.initials: M
authors.lastname: Bromwich
authors.forename: Shanmugam
authors.initials: S
authors.lastname: Murugappan
authors.forename: J Paul
authors.initials: JP
authors.lastname: Willging
mesh_terms: D001999:Bronchoscopy / Q000379:methods*; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008953:Models, Anatomic; D010865:Pilot Projects; D011446:Prospective Studies; D014057:Tomography, X-Ray Computed; D014741:Video Recording