Comparison of Airway Measurements for Tracheobronchial Stenosis Between Stereoscopic Bronchoscope and MD-CT.

Background: Stereoscopic bronchoscopy is a new diagnostic tool to measure the diameter and cross-sectional area of the airway. The stereoscopic bronchoscope, which operates the same as a standard bronchoscope, utilizes 2 lenses to measure the airway using the principles of triangulation. Furthermore, the stereoscopic bronchoscope has the capability to measure the size of the airway during intervention in real-time, including variable stenosis. Materials and Methods: To prospectively compare preoperative stereoscopic and multidetector computed tomography (MD-CT) images to select the appropriate stent size for airway stenosis. Stereoscopic and MDCT images were then measured to confirm the correct placement of the stent. Results: Airway stenting was performed on 21 consecutive patients of whom, 15 were diagnosed with malignant and 6 with benign diseases. In total, 165 measurements were taken (134 healthy; 31 affected). For the diameter, BlandAltman plots were used to measure data from 165 matched stereoscopic and MD-CT measurement sites (bias, 0.40 +/- 2.86mm SD; percentage error, 33%), 134 healthy sites (bias, 0.554 +/- 2.83mm SD; percentage error, 34%), and 31 affected sites (bias, 1.20 +/- 2.67mm SD; percentage error, 52%). For the cross-sectional area, matched stereoscopic and MD-CT measurements were analyzed for 65 sites (bias, -10.53 +/- 92.85mm(2) SD; percentage error, 89%), 49 healthy sites (bias, -9.88 +/- 39.00mm(2) SD; percentage error, 32%), and 16 affected sites (bias, -13.12 +/- 48.81mm(2) SD; percentage error, 92%). Conclusion: Stereoscopic bronchoscopy was able to accurately measure the size of the airway during intervention, to assist in selecting the appropriate size of the stent.