Imaging Studies
See the list below:
-
CT scanning in an axial plane has been used to show the presence of a patulous eustachian tube.
-
CT scanning may be useful in making the diagnosis in some patients.
-
Radiology only assists in the diagnosis of anatomic patency.
Other Tests
See the list below:
-
Tympanometry may detect movements of the tympanic membrane with nasal respiration, especially with the patient in an erect position. [2]
-
Distorted sounds of nasal respiration and speech may be heard with a microphone placed in the external meatus.
-
With sonotubometry, a test sound is introduced into the nasal vestibule and a microphone is fitted into the external auditory meatus. With a patulous tube, sound pressure level in the external canal is at a maximum; because the tube does not close, no sudden drop in transmitted sound occurs.
-
Observe a regular change in middle ear pressure when increasing or decreasing the ambient pressure during the measurement of impedance in a pressure chamber. Usual variations in pressure with opening and closing of the tube are not seen because the tube remains open all of the time.
Diagnostic Procedures
See the list below:
-
In some patients with patulous tube, direct nasopharyngoscopy may show the continuous presence of a triangular opening of the eustachian tube orifice.
-
Transnasal endoscopic (video analysis) exam has been used to study the nasopharyngeal opening of the eustachian tube during rest, swallowing, and yawning.
-
Anatomy of the ear.
