Subperiosteal Abscess in Children after Cochlear Implant

Acute mastoiditis (AM) after cochlear implantation (CI) is rare and a recent systematic review identified only 43 such patients. Out of the 43 patients only 12 had a subperiosteal abscess (SPA). This condition presents the challenge of infection control, while preserving the implant.

We demonstrate below, the clinical course and management of a group of children with acute mastoiditis after cochlear implantation.

Out of approximately 200 implants in 140 children during a 10 years period, we identified 4 patients who developed AM. They all presented with a SPA. All patients were females and had ranged from 32 to 67 months of age. All patients recovered uneventfully with either incision and drainage or aspirations of the abscess with parenteral antibiotics, without performing a revision mastoidectomy. The table shows the clinical characteristics of the patients.

Comment

Otitis media prone children who undergo CI require careful clinical monitoring for infectious complication, mostly developing AM. In our limited case series, in contrary to the literature, all the patients developed SPA, thus requiring intervention.

The lack of the boney cortex over the mastoid after CI surgery has two important implications:

1. Pus from the mastoid and middle ear readily extend to the periosteal layer.
2. The electrode array exiting the speech processor and entering the mastoid is quite vulnerable, so performing a revision mastoidectomy jeopardizes the electrode array. Accordingly, management of the abscess and the mastoid should be conservative, if possible.

We found that repeated aspirations or incision and drainage were sufficient for managing acute mastoiditis with SPA in CI recipients. A vetilatio tube can also be considered in the longe term management of theotitis media prone child with a CI.