Benign abnormalities and carcinoid tumors of the central airways: Diagnostic impact of CT bronchography

OBJECTIVE. The purpose of this retrospective study was to determine the add ed diagnostic value, if any, of CT bronchography for the detection and char acterization of beni,on abnormalities and typical carcinoid tumors of the c entral airways. MATERIALS AND METHODS. We used bronchoscopy and helical CT to examine 238 b ronchial sections in 28 patients with 32 bronchial abnormalities and in fiv e patients with normal bronchoscopy results. Postprocessing consisted of CT bronchography based on surface rendering. Images were interpreted independ ently by two observers (a radiologist and a pneumonologist) who were not in formed of the bronchoscopy results. After initial interpretation of axial C T scans, the observers analyzed the axial CT scans with CT bronchograms. Re sults were evaluated for gain in diagnostic accuracy and in confidence. RESULTS. Mean sensitivity for detection of abnormal bronchial sections was 89% (range, 87-90%) for axial CT and 92% (range, 90-94%) for axial CT with CT bronchography (not significant). Mean specificity of both approaches exc eeded 99%. A correct diagnosis of the nature of the bronchial abnormalities was proposed for 68% of the cases in which axial CT was used alone and in 76% in which both axial CT and CT bronchography were used (not significant) . The addition of CT bronchography significantly increased the confidence o f the pneumonologist in the diagnoses. CONCLUSION. Axial CT remains the technique of choice to detect and characte rize benign abnormalities of the airways. CT bronchography provides little diagnostic gain but increases the confidence of chest physicians in the int erpretation of CT scans for the assessment of benign abnormalities and typi cal carcinoids of the central airways.