Ectopic meningioma: a case report with a literature review

Abstract

Ectopic (extradural) meningiomas that do not originate from either the optic fascicle or the intracranial meninges are exceedingly rare. A patient with an ectopic meningioma in the external auditory canal and mastoid was treated in our unit. The world literature of the last 20 years was reviewed.

Primary meningioma of the middle ear

“…These have consisted of extracranial meningioma presenting as an aural polyp with conductive hearing loss, 4 meningioma arising from the external auditory canal presenting with sagging of the posterior canal wall, 3 and one case which, similar to this case, presented with hearing loss and a mass behind the tympanic membrane which was subsequently found to occupy the mastoid antrum and epitympanum. 5 …”

“…1 Embryologically, it is suggested that ectopic meningiomas could arise from punched-off arachnoid cells outside the neuraxis lying along the line of fusion of primitive nerve and bone sheaths. 3 …”

Middle ear meningioma associated with coclear implant: special attention

“…Embryologically, ectopic meningiomas are postulated to arise from either ''punched off'' embryonal arachnoid cells outside the skull and vertebra that lie along the line of fusion of the primitive nerve or bone sheaths, or it may arise as a result of differential maturation of pluripotent mesenchymal cells (2,7). The first theory is more widely accepted.…”

“…Others features included otitis, polyp in the external ear, headaches, dizziness, unsteadiness, vertigo, disequilibrium, tinnitus, otalgia, bleeding, "metallic taste," chronic cough, facial palsy or facial spasm, temporo-mandibular joint dysfunction or a neck mass (7).…”

“…Treatment of primary ear meningiomas is surgical excision (7). The nature of surgery depends on the extent of the tumour, which needs careful preoperative assessment with MRI scans.…”