Retromastoid osteoma—a rare case report

Abstract

Osteomas are slow growing bone tumours and are often asymptomatic. Rarely, they can be present in the temporal bone—only few cases had been reported, with an incidence of 0.1–1%. We describe a case of an osteoma of the temporal bone (retromastoid) found in a 40 year old female, who presented with a slow growing swelling behind the right ear for 9 years. Diagnosis was made on non-contrast computed topography (CT) of the skull. Treatment is indicated in symptomatic cases or cosmetic reasons. Screening colonoscopy and genetic testing for familial adenomatous polyposis (FAP) and Gardner’s syndrome are advised.

Mastoid osteoma: A rare incidental finding in an orthodontic patient

“…The etiology of mastoid osteoma is still unknown, but the accepted theories of mastoid osteoma include congenital, infectious, and traumatic origins. 1,12,19,20 In our case, a congenital origin was deemed to be most likely because the patient reported no previous infection or trauma.…”

“…14 Mastoid osteomas are temporal osteomas attached to the cortex of the mastoid bone and are very rare, representing about 0.1% to 1% of all benign tumors of the skull. 1 3 5 6 15 16 17 Mastoid osteomas have a higher incidence in females, predominantly in the second and third decades of life. 3 18 Our patient supports these tendencies.…”

“… 23 However, mastoid osteoma may present signs and symptoms such as facial palsy, the sensation of ear fullness, pressure-related pain, hearing loss due to meatal obstruction, and chronic discharge. 1 3 21 In a case report, Van Dellen 24 described a mastoid osteoma causing intracranial complications due to displacement and compression of structures in the posterior cranial fossa. Another report described a trauma-related mastoid osteoma in a 19-year-old woman with recurrent postauricular pain.…”

“…Osteomas are benign, slowly growing, osteoblastic mesenchymal tumors that may be classified based on their location, size, and extension. 1 In the head and neck, osteomas are found mostly in the frontal and ethmoid sinuses. Temporal osteomas are rare and most frequently involve the external auditory canal, which may cause occlusion of the external meatus and deafness.…”

“… 3 Mastoid osteomas are rare tumors composed of well-differentiated osseous tissue in a laminar and circumscribed arrangement arising from the cortex of the mastoid body and growing outward from the external surface of the mastoid process. 1 2 3 4 5 6 …”