Changes in tympanograms after middle ear inflation.

To determine the effects of politzerization or middle ear (ME) inflation by a catheter, we studied the ME pressures in 35 ears with retracted tympanic membranes (29 patients). Serial tympanometries were performed prior to the ME inflation and immediately, 10, 20, 30 and 60 min after the procedure. The present study showed that the more negative the ME pressure was before the inflation, the greater the pressure change was after the treatment. The elevated ME pressure induced by the procedure declined rapidly within the first 20 min after the inflation. This was probably caused mainly by spontaneous elimination of ME gas through the eustachian tube and gas absorption from the ME mucosa. During the post-inflation course, some ears demonstrated more negative pressures in the ME cavity than those before the inflation. The present investigation demonstrated that the use of inflation to treat secretory otitis media had short-term benefits which could be improved by minimizing gas absorption.