Clinical assessment of eustachian tube ventilatory function.

Abstract

AbstractThe persisting incidence of middle ear effusion subsequent to the advent of antibiotics and the development of a sophisticated microsurgical armamentarium and technique has been the continuing impetus to arrive at a method for evaluating eustachian tube function. The aspiration test developed by Flisberg, et al., has been thought to test most satisfactorily physiological tubal function by measuring the capability of the tube to equilibrate an induced negative pressure in the middle ear by deglutition.This technique was utilized to evaluate tubal function in 92 ears with tympanic membrane perforations. In 21 ears perforation was the result of trauma, recent but not acute. The remaining 71 ears have persistent perforations as a result of chronic otitis media; 18 ears were actively draining when they were tested; 53 ears were dry, without evidence of drainage, at the time of test.This investigation has shown that ears presenting dry perforations as a result of chronic otitis media demonstrate a continuum of function from full capability to reduce negative pressure to total inability to reduce such pressures; that no discernable difference in eustachian tube performance exists, however, among ears with quiescent perforations as a result of trauma or chronic otitis media; that active drainage manifesting an inflammatory mucosal process further severely compromises tubal ventila‐tory function by facilitating “locking” at high negative pressures; that age, while exerting some influence on the tube, in that adults show some increased capability for tubal function and some compromise in such function is present in childhood, that the influence of age is hardly striking; that tubes manifesting a total inability to reduce negative pressure do tend to be associated with ears with recurrent or refractory mucosal disease.However, this technique may also be challenged. It has been suggested that normal tubes should be capable of reducing negative pressure to within zero to ‐50 mm H2O. Other studies, however, have shown little correlation between middle ear pressure as measured by tympanometry and tubal function tested by this method. A disparity also exists in the high incidence of poor tubal function by this technique as compared to the success rates in tympanoplasty in existing large series; that while some investigators are able to demonstrate the tendency for poorer results in ears with poor tubal function testing, prediction of surgical success and failure is feasible in only a minority.It is the conclusion of this study that a negative result in testing for eustachian tube function is not a contraindication to tympanoplasty, and it is difficult to enthusiastically support this test as being capable of measuring the physiological normal of the tube or as a prognostic indicator to results in tympanoplasty.