Osteoma of the promontory: a case report

Incidentally detected middle ear osteoma: two cases reports and literature review

Osteomas of the middle ear are rare benign neoplasms. To date, only a few cases have been reported. Osteomas of the middle ear are small, single, usually unilateral, peduncular growths, off-white in color, with a smooth or multilobular surface, asymptomatic or causing functional disorders. The most common symptom is conductive hearing loss because of impingement of the ossicular chain. Some cases are asymptomatic and are diagnosed incidentally. We present two cases of incidentally detected middle ear osteoma. Based on a review of the main articles in the literature and analysis of two cases managed in our department, we describe the clinical spectrum, etiology, and management of middle ear osteomas.

Osteoma of the promontory mimicking a congenital cholesteatoma

Osteoma of the temporal bone most commonly occurs in the external ear. Osteomas in the middle ear are not common, and only 25 relevant cases (18 papers) have been reported in the English literature. With only 5 cases reported to date, osteoma of the promontory in the middle ear is rare. This study reports a case of asymptomatic osteoma of the promontory in the middle ear mimicking a congenital cholesteatoma in a 4-year-old girl.

Osteoma of the incus with congenital cholesteatoma: a case report

Osteomas of the middle ear are rare benign tumors. They commonly arise from the promontory. To date, a total of three cases of osteomas of the ossicles, inseparable from malleus and incus, have been described in the English literature. Among them, only one case osteoma with congenital cholesteatoma has been reported. Recently a 6-year-old boy with osteoma associated with congenital cholesteatoma presented to our service. The osteoma and congenital cholesteatoma were removed successfully by canal wall up mastoidectomy with staging operation. A rock-hard mass was separated from the footplate. The malleus and short process of incus were intact. Histopathological examination confirmed the presence of the osteoma.

A huge osteoma of the middle ear

Osteomas of the middle ear are rare benign neoplasms. Most of the cases caused conductive hearing loss and others were asymptomatic and diagnosed incidentally. We report a case of a huge middle ear osteoma along with compatible radiological findings filling the whole tympanum and the Eustachian tube, which caused intermittent otorrhea and conductive hearing loss.

Fibro-osseous lesions of the external auditory canal

OBJECTIVES

To differentiate a novel type of benign circumscribed bone lesion of the external auditory canal from those described previously, such as exostoses and osteomas.

STUDY DESIGN

Information was obtained from computed tomography (CT) images, surgical findings, and pathologic study.

METHODS

Five patients (26 to 82 years old) who presented a hard, round, unilateral, skin-covered mass occluding the external auditory canal to varying degrees were studied. A CT study carried out before resection of the lesions by curettage disclosed the absence of a bony connection to the underlying structures. All the tissue specimens underwent pathologic study.

RESULTS

CT and surgical findings demonstrated the absence of a connective pedicle. The pathologic findings showed lesions consisting of an osteoma-like bone formation with sparse osteoblastic areas; mature lamellar bone was observed in three cases, bone marrow containing adipose tissue and hematopoietic remnants in two, and a dense, collagenous stroma in another. They all showed irregular trabeculae, bordered by osteoid osteoblasts. In no case was there evidence of a relationship to the cartilaginous tissue or to the bony structures of the external auditory canal.

CONCLUSIONS

The data obtained from the clinical, CT, surgical, and pathologic findings suggest the existence of a lesion unlike those previously known, possibly related to ossifying reactions in other parts of the organism.