Nonneoplastic Tracheal Abnormalities on CT

Tracheal disorders can create clinical and imaging challenges. They are often misdiagnosed as other pulmonary disorders. Chest radiography has low sensitivity and specificity for proper identification of tracheal disorders. Multidetector-row CT (MDCT) has the inherent advantage of being able to provide high-quality multiplanar reformations, 3D volume-rendered images, virtual bronchoscopy, and minimum intensity projections. These can serve as a roadmap for bronchoscopy or surgical planning. The most important imaging sign of tracheal disease is thickening of the tracheal wall, and the most relevant sign to be evaluated for differential diagnosis is the distribution and appearance of wall thickening. Tracheal abnormalities may be classified based on the tracheal dimensions into increased diameter or decreased diameter to reduce the differential diagnosis. Increased diameter tracheal diseases may be subclassified into diffuse or focal diseases based on the area of involvement, thereby providing a more specific diagnosis.