Ossicular chain reconstruction using costal cartilage in malleoincudal osteoma

To report an extremely rare case of malleoincudal osteoma that led to conductive hearing loss despite an unusually normal otomicroscopic appearance, and to highlight the usefulness of costal cartilage for ossicular chain reconstruction after tumour removal.

A 37-year-old woman presented with a 2-year history of progressive, right-sided hearing loss. Physical examination revealed a normal tympanic membrane. Pure tone audiometry showed a right-sided conductive hearing loss. High-resolution computed tomography revealed a right-sided epitympanic mass arising from the malleus head and contiguous with the incus. The patient underwent a closed mastoido-epitympanectomy. The malleus head and the incus with associated malleoincudal osteoma were removed. Ossicular chain reconstruction using costal cartilage was performed at the time of tumour removal.

The possibility of a middle-ear osteoma must be considered in cases of unilateral and progressive conductive hearing loss with a normal otomicroscopic appearance in patients with no history of ear infection, trauma or prior surgery, and with no family history of hearing loss. Surgical treatment is indicated in cases of significant conductive hearing loss. To our knowledge, this is the first case report of malleoincudal osteoma in which the ossicular chain was reconstructed using costal cartilage.