Homograft tympanoplasty in perspective

Abstract

Despite over 4 000 reported successful tympanoplasties using homograft (allogenous) preserved tympanic membranes and ossicles, general scepticism regarding this technique persists. Review of the literature indicates why:

• there are wide discrepancies for indications, preservatives, surgical techniques and results,

• several surgeons have not duplicated the 95% success rate reported by Marquet and Wehrs,

• animal experiments have consistently failed,

• the host immunological response is still questioned,

• data on histological fate of the donor TM is limited,

• indications for instances when homograft tympanoplasty would prove superior to standard techniques have not been clearly established.

This study had limited the use of homograft TMs to those cases in which standard tympanoplasty techniques have already failed to produce a satisfactory anatomical or hearing result (recurrent perfora­tions, lateralized TMs, draining radical mastoidectomy cavity) or to those cases where standard techniques have a high incidence of failure, (i.e. slag burns, total perforations with absent malleus, con­genital atresia). Documentation of long-term anatomic and hearing results (4 ½ yrs mean follow-up) are presented for 125 consecutive patients in whom formalin-fixed homograft TMs were used to recon­struct the severely damaged middle ear.

At the completion of this study, 95 % (119/125) of the homograft tympanoplasties are currently intact. There were 13 immediate post­operative perforations, but 11 were repaired with a second-stage underlay fascia tympanoplasty. Long-term hearing results were ana­lyzed according to the type of ossicular reconstruction employed (mean follow-up 4 yrs). In 87 patients with chronic otitis media, 94 % of the type I repairs maintained an air/bone gap of 25 dB or less, 85 % of type II, and 81 % of type III.