Sonotubometry in Chronic Ear Disease

Abstract

\s=b\Aeration of the tympanic cavity was studied after 81 operations were performed on ears with cholesteatoma, in which sonometry was used preoperatively to measure the eustachian tube (ET) function. Twenty-nine of the 44 ears in which all or part of the tympanic mucosa could be preserved had positive sonometric test results, and 25 ears (86%) retained satisfactory aeration. Eight (53%) of the 15 ears with negative test results showed good postoperative aeration while adhesive changes developed in seven ears (47%). In 37 ears after the removal of all tympanic mucosa, aeration was satisfactory in eight (55%) of the 15 ears with positive sonometric test results, whereas only three (14%) of the 22 ears with negative test results developed an aerated tympanum. A positive sonometric test result can be regarded as a fair prognostic indicator of normal ET function. In extensive tympanic disease, there is a clear correlation (86%) between a negative test result and postoperative adhesion. (Arch Otolaryngol 1984;110:596-599) Measurement of the eustachian tube (ET) function in a reliable way is one of the most difficult ques¬ tions in the preoperative examination of patients with chronic ear disease. In fact, some surgeons consider the results so conflicting that they do not perform any ET function tests at all. Sophisticated tests may be time-con¬ suming and considerations of cost effectiveness may result in omission of earlier used tests, if it is believed that the results are not worth the effort.Apart from the experimental labo¬ ratory tests, Flisberg's negative pres¬ sure equalization test1 and Virtanen's sonometric ET test2 are the only two tests simple enough for routine clini¬ cal use. We no longer use Flisberg's test because of the many false-nega¬ tive results associated with the -200mm water pressure equalization. Not even among simple myringoplasty candidates were the majority able to fully equalize the pressure, whereas preoperative sonometric examination was positive in 90% of the cases.3 This experience is also in accordance with clinical experience.In our earlier clinical evaluation,3 we had included 44 ears of patients undergoing extensive surgery for chronic ear disease. Preoperatively, only half of these ears had a normal sonometric test result. In the other half, there was no sound transmission to the external meatus. This again is in accordance with the clinical experi¬ ence in ears with a diseased tympanic cleft. This report describes the results obtained in a series of ears receiving tympanomastoid surgery for chronic ear disease. The patients were fol¬ lowed up in the department of otolar¬ yngology to assess postoperative ET function and aeration of the tym¬ panum. The follow-up results were re¬ lated to the preoperative sonometric evaluation of the ET. PATIENTS AND METHODSThe series includes 81 ears of patients with cholesteatoma who were operated on between 1977 and 1981. The ages of the patients ranged from 10 to 78 years (mean, 39 years) and the duration of the follow-up period was one to fo...