Computed tomography in the study of the eustachian tube.

A CT study was made of the eustachian tube in normal subjects as a control group and patients with chronic pathological inflammation of the middle ear. CT made it possible to perform contiguous scans at homologous depths of 1.5 mm, showing the whole interior of the tube in clear detail: the protympanum, the bony and cartilaginous portions, and the nasopharyngeal orifice. In most of the cases of pathological middle ear inflammations, the eustachian tube lumen was seen to be constricted and obstructed with isodense matter. Our present results also show the importance of extending CT investigations beyond the tympanic cavity and the mastoid to the eustachian tube in order to have more clinical data on its condition.