Atelectasis, retraction pockets and cholesteatoma.

Abstract

This is a quantitative study of tympanic membrane atelectasis and retraction pocket dynamics. 308 ears. affected by various types of atelectasis were followed up for 9 years (average 3 years). 74 of these evidenced retraction pockets of the pars tensa and 127 retraction of the pars flaccida. The phenomenon of tympanic membrane atelectasis and retraction was found to be unstable. The condition of most ears improved or became stabilized, while in others (the minority, 10–20%) it deteriorated. This middle ear dynamics was observed irrespective of whether the ears were treated or not. The deterioration trend (of 10–20% of the ears) showed a progression from mild atelectasis all the way to deep retraction pockets. One retraction pocket of the membrana tensa (2%) and two of Shrapnell's membrane (2%) progressed and became small attic cholesteatomas. A steady linear increase in average age was observed, as one proceeds from a milder to a more severe degree of atelectasis. However, on reaching severe atelectasis or large retraction pockets, the mean age was found to be the same as that of a large control group of attic cholesteatomas. This latter finding suggests that while this study shows that retraction pockets to originate in atelectatic conditions and retraction pocket cholesteatomas may originate from retraction pockets, it is still doubtful whether this mechanism can account for all the middle ear cholesteatomas and epidermoid cholesteatomas we encounter. Other additional etiological processes should also be taken into consideration. The treatment of most atelectatic ears and mild retractions can be conservative. Follow-up of these ears is important. however. Once hearing has deteriorated or a non-cleansing pocket formed. ossiculoplasty. as well as replacement of the drum. is often indicated—and gratifying.