Imaging the airways. Computed tomography and magnetic resonance imaging.

Both CT and MRI are significant advances in the diagnostic imaging of the trachea and bronchi. Because of its ability to image the airways in cross section with high spatial and contrast resolution, CT has gained wide acceptance in the evaluation of tracheobronchial diseases. Although the spatial resolution of MRI is less than that of CT, MRI offers the advantages of multiplanar imaging, high contrast resolution without use of intravenous contrast agents, and absence of ionizing radiation. Although to date the role of MR in evaluating the trachea and bronchi has been limited, it may be anticipated that the list of indications will continue to expand with advancing technologic developments.