Learning Objectives:

Introduction: Since 2009, we perform tympanoplasty (TP) without mastoidectomy (w/o M) for chronic otitis media (COM), aiming preservation of the ventilating function in the mastoid air cells. In this paper, clinical outcomes of that surgery were reviewed.

Methods: We analyzed 54 cases with COM, who underwent the first operation of TP w/o M. Age distribution was 8–78 (median 61) and the minimum follow-up period was 12 months. We compared the rate of complete closure, hearing outcome, and preoperative CT findings between type I and type III cases. As for hearing, successful outcome means meeting one of the following criteria using an average (0.5, 1.0, 2.0 kHz); 1. Air-bone gap is less than 15db. 2. Hearing threshold improved more than 15db. 3. Hearing threshold is less than 30db.

Results: Type I TP was performed in 31cases and type III TP was done in 23 cases. Autologous bone was used as columella in all cases with type III TP. The TM closure rate of type I and type III at 12 months follow-up was 74.2% and 82.6%, respectively (p = 0.68). The successful hearing rates of type I and type III were 80.6% and 78.2%, respectively (p = 0.82). Only 1 case with type I TP presented with soft tissue density area in the mastoid in the preoperative CT, whereas 16 cases with type III TP was shown to have such area. There was no statistically significant difference in TM closure rate between cases with and without soft density area in the mastoid (81.2% vs. 85.7%, p = 0.35).

Discussion: There was no significant difference in either TM closure rate or hearing outcome between type I and type III. In type III TP, incus and the head of malleus are usually removed to secure the ventilation route from the Eustachian tube through the mastoid. This may be the reason for less disadvantage of TP w/o M even for COM with mastoid granulation. Another factor should be searched on the failure of TP w/o M.

Conclusion-Type III TP w/o M has similar benefit to type I TP even on COM with mastoid granulation.