Revision surgery for chronically discharging mastoid cavities: mastoid obliteration with canal wall reconstruction versus non-obliteration surgery

Purpose: To evaluate the surgical results of revision canal wall down (CWD) surgery for chronically discharging mastoid cavities and to compare the non-obliteration approach to mastoid obliteration with canal wall reconstruction.

Methods: This is a retrospective cohort study. All adult patients (≥ 18 years) who underwent revision surgery for chronically draining mastoid cavities between January 2013 and January 2020 were included. Primary outcome measures included the dry ear rate, complications and postoperative hearing.

Results: 79 ears were included; 56 ears received revision CWD with mastoid obliteration and posterior canal wall reconstruction and 23 ears received CWD without mastoid obliteration. The dry ear rate at the most recent outpatient clinic visit (median 28.0 months postoperative) was significantly higher in the obliteration group with 96.4% compared to 73.9% for the non-obliteration group (p = .002). There were no differences in audiological outcome and incidence of complications between the two techniques.

Conclusion: We show that in our study population revision CWD surgery with mastoid obliteration and posterior canal wall reconstruction is superior to revision CWD surgery without mastoid obliteration in the management of chronically discharging mastoid cavities. In the obliteration group, a dry ear was achieved in 96.4% as this was 73.9% in the non-obliteration group. We found no differences in audiological outcome and in incidence of complications between the two techniques.