Computed tomography of the trachea: normal and abnormal.

The trachea was investigated by means of computed tomography (CT) in 50 patients without tracheal or mediastinal abnormalities and in 39 patients with various diseases of the trachea. The variations in the normal CT appearances of the trachea and surrounding structures are described. CT did not provide additional information in the detection or characterization of tracheal stenosis beyond that obtained from more conventional studies, including tomography and positive-contrast tracheography. In patients with a saber-sheath trachea, CT demonstrated the abnormal configuration of the tracheal cartilages and abnormal collapse of the trachea on forced expiration. In patients with primary or secondary neoplasms involving the trachea, CT was most accurate in defining the intraluminal presence of tumor, the degree of airway compression, and the extratracheal extension of tumor. CT can be of value in determining the resectability of primary tracheal neoplasms and the planning of radiation therapy in metastatic lesions to the trachea and surrounding mediastinum.