Long-Term Outcomes of Mastoidoplasty and Its Feasibility for Hearing Aid Usage

To evaluate the long-term outcomes of our novel mastoidoplasty (MP) using demineralized bone matrix (DBM) and to compare its feasibility for hearing aid (HA) usage with conventional mastoid obliteration (MO) with inferiorly based periosteum.

A total number of 112 patients undergoing canal wall down mastoidectomy (CWDM) with mastoid reconstruction by MO (n=58) or by MP (n=54) between 2012 and 2022 who were followed up for more than 2 years were included in this retrospective study. Long-term surgical outcomes and the feasibility for hearing aid usage were evaluated by comparing the results of the postoperative EAC diameters measured by temporal bone CT scan, and HA adoption rates between the MP and MO groups.

The MP group demonstrated superior EAC stability and feasibility for postoperative HA usage compared with the MO group. The MP group showed smaller axial (8.13±3.24 vs. 9.04±2.42 mm, P =0.012) and coronal (10.13±2.53 vs. 11.52±3.06 mm, P =0.014) EAC diameters compared with the MO group, indicating a more feasible condition for canal-type hearing aid usage. Postoperative HA adoption rates were significantly higher in the MP group (60% vs. 42.3%), with shorter time to adoption (9.33±12.82 vs. 24.14±27.03 mo, P =0.040) compared with the MO group.

Compared with MO with periosteal flap, MP utilizing DBM showed better long-term outcomes of EAC reconstruction for hearing aid adoption with its smaller EAC sizes as well as a higher HA adoption rate. MP also resulted in a faster hearing rehabilitation with hearing aids compared with MO. We propose that MP should be considered for optimizing anatomic and functional outcomes in CWDM patients requiring further hearing rehabilitation with a hearing aid.