Timothy C. Hain, MD. • Page last modified: July 16, 2022Return to testing index

The purpose of this test is to detect perilymphic fistula and related conditions such as superior canal dehiscence. If pressure sensitivity is found, one of these conditions ismore likely.

Bedside fistula tests

Fistula Test

Pressure is applied to each ear in turn, and eye movements are recorded.

The picture above shows Dr. Hain using a Brunnings otososcope to deliver pressure.

Fistula testing can also be done at the bedside as illustrated above. Pressure is applied to the ear through one of the devices listed (1-hand bulb with tympanometer tip, 2-Brunnings otoscope, 3-tympanometer), and eye movement is either directly observed or measured with a video-frenzel goggle device.

Illustrations of positive fistula tests can be found on the page concerning pressure senstivity --

We do not recommend this test.



Posturography fistula testing (no longer commercially available).

Pressure Test
Pressure traces

The two traces above show a pressure test that was thought to be an indication for fistula surgery on the left ear. There is clearly more sway when pressure is placed into the left side. This equipment, originally produced by NeuroCom, is no longer commercially available, but a few units may still be in the field. We do not recommend this test .

Ben-David and others (1997) suggested that posturography was effective in diagnosing Tullio's phenomenon (sound sensitivity, associated with fistula as well as other conditions such as SCD). This use appears reasonable to us, although it is puzzling why more has not been published as of this date (2002). It does seem to us that it might be difficult to distinguish findings related to suggestibility, from organic findings, as we see no practical way to prevent the patient from knowing that there is pressure or sound stimulation exerted in the ear in question.