EUSTACHIAN-TUBE FUNCTION IN CASES OF EPITYMPANIC RETRACTION POCKETS

There are different hypotheses for the development of epitympanic retr action pockets. These can occur as the result of an inflammatory proce ss and negative pressure in the middle ear spaces. Anatomic bottleneck s in the middle ear favor diminished inflation of the epitympanic spac e. The eustachian tube provides pressure equilibration in the middle e ar. Its dysfunction involving tubal opening or closing is thought to b e the main reason for a permanent negative pressure in the middle ear. A patulous eustachian tube is now claimed for prolonged negative pres sure in the middle ear and is caused by a so-called ''sniffing'' habit . The purpose of this study was to elucidate objectively the frequency of patulous eustachian tubes in ears with epitympanic retraction pock ets. We examined passive tubal function in 41 patients with 50 epitymp anic retraction pockets by using dual impedance in a pressure chamber. We identified three stages of epitympanic retraction pockets. Stage 1 involved a mobile and controllable retraction pocket; stage 2 corresp onded with a fixed but controllable pocket, whereas stage 3 described a fixed pocket that was developing into a cholesteatoma. Results were compared with the function tests of 100 healthy ears in 50 normal indi viduals. We found 27 patulous eustachian tubes in patients with epitym panic retraction pockets, 22 of which occurred in affected ears while only 2 patulous tubes were found in the group of the healthy ears. Tub al opening pressure (P<0.001) and tubal closing pressure (P<0.01) were significantly lower in ears with epitympanic retraction pockets than in healthy ears.