The Silverstein permanent aeration tube in tympanoplasty.

Hearing improvement for cases of chronic ear disease has become one of the goals of tympanoplasty. Although great strides continue to be made toward this goal, one enigma which frustrates even the most carefully performed tympanoplasty is the blocked or non-functioning eustachian tube. Early attempts to overcome this problem consisted of passing polyethylene tubing through the eustachian tube and out the nose, Zoller, or drilling out the tubal orifice, Wullstein. Other articles recommended rerouting the eustachian tube through the maxillary sinus or reconstructing its normal course by a middle fossa approach. Herbert Silverstein first introduced the idea of a permanent indwelling silastic aeration tube for treatment of chronic serous otitis media in 1970; he also described its use in ears with ossicular problems and poor eustachian tube function. He places this tube by drilling a hole through the posterior inferior bony annulus of the middle ear or directly into the mastoid antrum. The Silverstein permanent silastic aeration tube has been found to be a valuable adjunct in tympanoplasty. This tube may be utilized at the time of the initial surgery or as a secondary procedure. It may be placed through the bony annulus of the middle ear or into a hole drilled to the mastoid antrum as described by Silverstein; however, in ears where the incus must be removed, the fossa incudis becomes the preferred location. Sixteen cases are reported in which the Silverstein permanent aeration tube was utilized in conjunction with tympanoplasty. The concept for use of this permanent silastic tube arose out of the frustrating experience of producing recurrent perforations in grafted tympanic membranes by the use of conventional aeration tubes; therefore, the following technique was adopted: a diagnostic myringotomy was performed and a polyethylene tube placed temporarily through the grafted tympanic membrane. If the hearing improved following the procedure the patient was scheduled for insertion of a permanent aeration tube. In selected cases the aerating device was used in conjunction with the original tympanoplasty. Postoperative care is simple and consists of cleaning crusts from within and around the tube. Although infections through the tube are infrequent, if they occur the tube may be removed as an office procedure. Overall hearing results have been gratifying. Six months following surgery 81 percent of the patients had closed the air bone gap to within 10 decibels or less and another 12 percent to within 20 decibels of the preoperative bone conduction. There was more loss of hearing in two of the 16 ears following this procedure, but in none was there a significant change in the discrimination score or the development of an unserviceable ear. Truly this is a detour and bypass procedure, and it would be much more physiologic and desirable to restore middle ear aeration through the normal eustachian tube; however, until a reliable, simple and consistent procedure can be devised, the Silverstein permanent aeration tube appears to fulfill the requirements of maintaining middle ear aeration with good hearing and function.