We evaluated the feasibility of ultrasonography for imaging of the trachea and its effectiveness in the diagnosis and follow-up of patients with tracheal stenosis due to various diseases. Twenty normal volunteers and six adult patients with tracheal stenosis were included in the study group. Subjects were examined with ultrasonography in a supine position with the neck hyperextended or in a sitting position. At the level of the thyroid isthmus, the anterior tracheal wall thicknesses imaged by ultrasonography were 1.54 +/- 0.22 mm (mean +/- SD) and 1.22 +/- 0.18 mm for normal male and female volunteers, respectively. Ultrasonography could reveal the intrinsic tracheal wall lesions and extrinsic lesions compressing the trachea in patients with tracheal stenosis. These ultrasonographic images correlated with CT images. In conclusion, ultrasonography may be useful in imaging of the trachea.