Labyrinthine Ossificans and Cochlear Implantation in a Case of Post Modified Radical Mastoidectomy

Abstract

Labyrinthitis Ossificans (LO) is the pathological ossification of the membranous labyrinthine spaces in response to an insult to the inner ear involving membranous labyrinth or the endosteum of the otic capsule.1 The pathogenesis of this condition is not well known. Earlier theories suggest that new bone formation could be metaplastic or osteoplastic. There are typically three phases of LO, acute, fibrotic and ossifying phase.2 The early identification of LO is important for hearing preservation, early intervention with possible cochlear implant placement, and alerting surgical colleagues to carefully evaluate obstruction during cochlear implant placement.3 Significant challenges related to the ability to place the cochlear implant arise with progression of LO and the extent of ossification throughout the membranous labyrinth, which may ultimately lead to alternative cochlear implant insertion techniques.4-5 Grade 2 labrynthine ossificans is the condition where a new bone or fibrous tissue replaces the 25-50% of the membranous labyrinth.
Here we report a case reported to us with the concern of hearing loss.