M. Kui et al., EVALUATION OF THE AIR BRONCHOGRAM SIGN ON CT IN SOLITARY PULMONARY-LESIONS, Journal of computer assisted tomography, 20(6), 1996, pp. 983-986
Purpose: Our goal was to evaluate the presence and the significance of
the air bronchogram sign in solitary pulmonary lesions (SPL) on CT. M
ethod: One hundred thirty-two patients with SPL who underwent chest CT
scans and had histological diagnosis were studied retrospectively. We
reviewed all chest CT scans to assess for the presence of the air bro
nchogram sign in the SPL and recorded the distribution of this sign in
malignant and benign lesions. The morphology of the aerated bronchi i
n the lesion and its significance in differential diagnosis were also
evaluated. Results: Of 17 cases of benign lesions, only 1 (5.9%) had a
n air bronchogram; of 115 lung cancers, 33 (28.7%) had this sign (p <
0.05). The encased bronchi exhibited four morphologic patterns: normal
, tortuous, ectatic, and cut-off. The morphology of the bronchus in th
e benign lesion was normal. However, bronchi in malignant lesions disp
layed all four types of morphology. The air bronchogram sign was seen
in all histologic types of lung cancer (squamous cell 10, adenocarcino
ma 9, bronchioloalveolar cell 12, small cell 1, non-small cell 1). Les
ions of different sizes were noted to have air bronchograms, including
those < 2 cm in diameter. Conclusion: The CT air bronchogram sign in
SPL is significantly more common in malignant than in benign lesions.
The sign is seen in all lung cancer cell types and demonstrates varied
bronchial morphology.