title: Toward online quantification of tracheal stenosis from videobronchoscopy.
abstract: OBJECTIVE
  Lack of objective measurement of tracheal obstruction degree has a negative impact on the chosen treatment prone to lead to unnecessary repeated explorations and other scanners. Accurate computation of tracheal stenosis in videobronchoscopy would constitute a breakthrough for this noninvasive technique and a reduction in operation cost for the public health service.
  
  
  METHODS
  Stenosis calculation is based on the comparison of the region delimited by the lumen in an obstructed frame and the region delimited by the first visible ring in a healthy frame. We propose a parametric strategy for the extraction of lumen and tracheal ring regions based on models of their geometry and appearance that guide a deformable model. To ensure a systematic applicability, we present a statistical framework to choose optimal parametric values and a strategy to choose the frames that minimize the impact of scope optical distortion.
  
  
  RESULTS
  Our method has been tested in 40 cases covering different stenosed tracheas. Experiments report a non- clinically relevant [Formula: see text] of discrepancy in the calculated stenotic area and a computational time allowing online implementation in the operating room.
  
  
  CONCLUSIONS
  Our methodology allows reliable measurements of airway narrowing in the operating room. To fully assess its clinical impact, a prospective clinical trial should be done.
authors.affiliation: Computer Vision Center, Computer Science Department, Universitat Autonoma de Barcelona, 08193, Barcelona, Spain, csanchez@cvc.uab.es.
authors.forename: Carles
authors.initials: C
authors.lastname: Sánchez
authors.forename: Jorge
authors.initials: J
authors.lastname: Bernal
authors.forename: F Javier
authors.initials: FJ
authors.lastname: Sánchez
authors.forename: Marta
authors.initials: M
authors.lastname: Diez
authors.forename: Antoni
authors.initials: A
authors.lastname: Rosell
authors.forename: Debora
authors.initials: D
authors.lastname: Gil
mesh_terms: D001999:Bronchoscopy / Q000379:methods*; D006801:Humans; D020407:Internet; D011446:Prospective Studies; D014132:Trachea; D014135:Tracheal Stenosis / Q000175:diagnosis* / Q000601:surgery; D014481:United States