Medical image of the week: tracheal stenosis

A 43-year-old woman was seen in clinic for dyspnea on exertion that began several months ago. Prior workup included a computed tomography of the chest with mild narrowing noted in the upper trachea. Pulmonary function tests (Figure 1) showed a flat inspiratory loop with a normal expiratory loop, which suggests a variable extrathoracic obstruction. On bronchoscopy, a tracheal stenosis was seen just past the vocal cords (Figure 2, Figure 3). Balloon dilation (Figure 4) of the stenosis returned the area to normal caliber