Evaluation of Tracheobronchial Lesions with Virtual Bronchoscopy; Correlation with Fiber Optic Bronchoscopy

Abstract

The aim of this study was to compare the diagnostic accuracy of 3-D virtual bronchoscopy (VB) with that of Fiber-optic (FB) bronchoscopy in patients who had symptoms of respiratory disorders. Thirty patients underwent VB examination. Thin section helical computerized tomography (CT) image were obtained. The volumetric data was downloaded to a workstation equipped with software for surface shaded rendering technique to achieve interactive 3-D virtual “fly-through” examinations of the tracheobronchial tree. Comparison was made between the results of 3-D virtual bronchoscopy, along with multiplanar reconstruction examination with the findings of conventional FB. This information was correlated with the surgical and pathological outcome wherever possible. Virtual bronchoscopy was true positive in twenty-four lesions. Further analysis revealed six cases were with strictures due to tracheobronchial tuberculosis or infection, eight were strictures due to carcinoma, five were endoluminal growths or polyps, three cases had nodes compressing the bronchi, one case had carcinoma of esophagus with tracheal extension and one had a congenital stricture. Virtual bronchoscopy was found false positive in one case, in which a polyp was misdiagnosed. Two endoluminal growths/ polyps were not appreciated on virtual bronchoscopy due to their small size and mild mucosal irregularity. Sensitivity, specificity, positive and negative predictive values were 96%, 50%, 92% and 66% respectively. To conclude VB represents a noninvasive method for evaluating helical CT findings. Further trials with larger sample size are needed on patient populations with any respiratory tract pathology, who do not have any gross findings on conventional examinations and are thus indicated for conventional bronchoscopy.