Computed tomography measurements for airway stent insertion in malignant airway obstruction

Background: Metallic airway stents for malignant airway obstruction are considered safe, yet are not without complications. This study reviews the role of computed tomography (CT) airway measurements for planning stent placement in malignant airway obstruction before the actual therapeutic procedure to avoid invasive diagnostic evaluation before the stent placement and to reduce complications. Methods: This study is a retrospective review of information from a stent order database and medical records of patients receiving stents for malignant airway obstruction at a university hospital over a 12-year period. CT scans were used to determine stent diameter by calculating mean diameters of healthy adjacent zones (proximal and distal), stent length (length of diseased airway), and location and number of potential stents. Results of CT planning before bronchoscopy were judged by complication rates. Results: Patient population consisted of 69 patients, 61.7±14.0 years old, 40 males, in whom 92 stents were inserted. The most frequent cause of airway obstructions was tracheobronchial cancer (32). All patients had nitinol stent placement; 66 stents were covered and 26 were uncovered. Follow-up time was 1 to 1067 days (median: 35 days). Complication rate was 10.1% and mainly involved the patients with tracheal obstruction (6). Complications included stent fractures (2), migration (2), granuloma (1), and infectious tracheitis (2). One early death within 24 hours after the procedure was not related to stent placement. Five patients required follow-up therapeutic bronchoscopy to treat the complications. Conclusions: These results suggest that prestent planning by noninvasive method of obtaining CT scan provides optimal stent size and position, possibly avoiding a diagnostic bronchoscopy and reducing complications. Further prospective study is needed to confirm these results because of limitation of this study's design.