title: Airway simulation to guide stent placement for tracheobronchial obstruction in lung cancer.
abstract: BACKGROUND
  To effectively palliate large airway obstruction in advanced unresectable lung cancer (stage IIIB or IV), we developed an airway imaging technique to guide selective endobronchial metallic stent placement.
  
  
  METHODS
  Fourteen consecutive patients with severe dyspnea (American Thoracic Society grade 4) had a combination of fiberoptic bronchoscopy, chest roentgenography, computed tomographic scanning, helical computed tomography with three-dimensional reconstruction, and intraluminal bronchography with selective bronchial guidewire placement under fluoroscopy to visually reconstruct and simulate the abnormal airway before and during stent placement. Wallstent or Gianturco intraluminal stents were used alone or in combination (up to five stents) to establish patency of the distal trachea and the major bronchi.
  
  
  RESULTS
  All 14 patients had successful deployment with initial relief of airway stenosis (>75% predicted diameter). No procedural complications were noted. However, technical problems included stent foreshortening and imprecision of placement, misinterpretation of bronchography (mucous versus tumor), and airway maintenance during manipulation. Length of stay attributable to the procedure averaged 4 days. Stent placement initially improved the dyspnea score in 7 of 14 patients. Five of 14 died in less than 1 month, with the remainder alive at up to 8 months' follow-up. Of those surviving more than 1 month, the Karnofsky score improved in 4 and was unchanged in 5, with 2 dependent (Karnofsky score <50), 3 functional (Karnofsky score, 50 to 70), and 4 active (Karnofsky score >70).
  
  
  CONCLUSIONS
  A protocol combining helical computed tomography with three-dimensional reconstruction, bronchography, and bronchoscopy allows accurate assessment of malignant airway obstruction to facilitate intralumenal stent placement for relief of stenosis. Patient selection to favor effective palliation and cost effectiveness has yet to be defined.
authors.affiliation: Department of Surgery, The University of Texas Medical Branch, Galveston 77555-0528, USA. jzwische@mspo2.med.utmb.edu
authors.forename: J B
authors.initials: JB
authors.lastname: Zwischenberger
authors.forename: G R
authors.initials: GR
authors.lastname: Wittich
authors.forename: E
authors.initials: E
authors.lastname: vanSonnenberg
authors.forename: R F
authors.initials: RF
authors.lastname: Johnson
authors.forename: S K
authors.initials: SK
authors.lastname: Alpard
authors.forename: S K
authors.initials: SK
authors.lastname: Anand
authors.forename: R J
authors.initials: RJ
authors.lastname: Morrison
mesh_terms: D000328:Adult; D000368:Aged; D000402:Airway Obstruction / Q000175:diagnosis / Q000209:etiology / Q000628:therapy*; D001980:Bronchi; D001995:Bronchography; D003362:Cost-Benefit Analysis; D004417:Dyspnea / Q000628:therapy; D005260:Female; D006801:Humans; D007902:Length of Stay; D008175:Lung Neoplasms / Q000150:complications*; D008297:Male; D008722:Methods; D008875:Middle Aged; D010166:Palliative Care / Q000379:methods; D018579:Patient Selection; D015607:Stents; D014057:Tomography, X-Ray Computed