Evaluation of tracheal stenosis: comparison between computed tomography virtual tracheobronchoscopy with multiplanar reformatting, flexible tracheofiberoscopy and intra-operative findings

Abstract

The aim of the study was to evaluate and compare various helical CT display modes [virtual endoscopy (VE)] and multiplanar reformations (MPR), conventional flexible tracheobronchoscopy (FT) and intra-operative (IO) findings in patients with tracheal stenosis and to analyze the advantage of MPR and VE in diagnosis and treatment planning and in postoperative follow-up. Thirty-seven patients with tracheal stenosis underwent standard neck and chest CT followed by MPR and VE. Results were correlated with the results of FT and IO findings. Thirty-three of the 37 stenoses were correctly graded and measured adequately using VE. Complete correlation among CT, fiberoptic tracheoscopy, and surgery of stenosis grading, stenosis length and length of planned resection segment of the trachea was noted between 33 of 37 patients with tracheal stenosis. Correlation between VE and IO was noted in 35 of 37 patients and between FT and VE was noted in 33 of 37 patients with tracheal stenosis. The sensitivity of VE was 94-97%, specificity was 100% with comparison to IO findings. The sensitivity and accuracy of MPR was 86-89% and specificity was 100% with comparison to FT findings. The results of the study indicate that VE is an excellent, consistent, and objective technique. VE with MPR is very useful in diagnostic evaluation and treatment planning in patients with tracheal stenosis.

Fig. 1

Axial image with measurement of the width (diameter) of trachea

Fig. 2

Virtual endoscopy showing concentric narrowing of the airway. a View of the proximal part of stenosis, b view of the distal part of stenosis

Fig. 3

Coronal image with measurements of stenosis. A length from the vocal cord, B length of planned segmental resection of trachea, C diameter of tracheal stenosis, D diameter of normal trachea

Fig. 4

3D shaded surface display

Fig. 5

Flexible tracheoscopy of tracheal stenosis

Fig. 6

Image of resected segment of trachea