Effect of direction of pressure change on obtaining airtight seals in tympanometry.

To determine the effect of change in pressure direction on obtaining a seal during tympanometry, an ascending approach (-/+) was attempted when the traditional, descending approach (+/-) was unsuccessful in maintaining an airtight seal. Results revealed that a seal was achieved using the ascending direction in twelve ears when the descending method failed; in only four ears, neither method was successful.