MDCT of the central airways: Anatomy and pathology

Approximately 25% of patients have subglottic stenosis and approximately 10% will have bronchial stenosis.8 Additional pulmonary findings on CT include pulmonary nodules and masses, some of which may be cavitary, consolidation and ground-glass opacities.2 Amyloidosis Amyloidosis is a rare disorder of unknown etiology characterized by deposition of abnormal proteinaceous material in extracellular tissues and various organs throughout the body. Other etiologies include long-term intubation, tracheal trauma, congenital abnormalities, chronic extrinsic compression in the setting of a vascular ring or sling, chronic inflammation, infection or may be idiopathic.1 On imaging, tracheomalacia is characterized by greater than 50% collapse of the intrathoracic trachea during forced expiration.1 With this disease process, the posterior trachea bows anteriorly during expiration, resulting in the appearance of a frown, the socalled "frown" sign (Figure 16).33 Tracheobronchomegaly Tracheobronchomegaly (MounierKuhn syndrome) is characterized by diffuse airway dilatation, which makes it unique from the other morphologic abnormalities of the central airways.