Solitary intracranial osteoma with attachment to the falx: a case report

Intracranial osteomas are uncommon lesions that usually arise from the inner table of the cranium. There are few reports in the literature of intracranial osteomas with meninges attachment and without direct relation with the skull bone; these osteomas were mostly attached with dura. We report a rare osteoma with falx attachment.

A 64-year-old woman presented with a 3-month history of intermittent tinnitus and dizziness. The scout film of petrous bone computed tomography scan revealed a high-density lesion in the frontal area. Magnetic resonance imaging showed a 2.5-cm mass attached to the surface of the falx in the right frontal parasagittal area. The patient underwent right frontal craniotomy, and a bony hard mass was found located in the right frontal parasagittal region extra-axially, with its medial surface attached to the falx. It could not be broken down by the cavitron ultrasonic surgical aspirator or even the cutting loop and was detached from the falx and removed in one piece. Histopathological examination showed a nodule with bony trabeculae and bone marrow tissue, compatible with osteoma. The postoperative course was uneventful, and the patient was discharged from the hospital with no neurological deficits one week after operation.

This is the first case report in the English literature of an intracranial osteoma arising from the falx. Because of their slow growth and their locations in silent brain areas, intracranial osteomas are usually diagnosed incidentally. Surgical resection is the primary treatment choice.