[Neurinoma of the major petrosus nerve]

Facial nerve schwannomas are rare benign tumors, when occurring, they are located most frequently in the distal fallopian canal and present as extracranial masses. The predominant symptom is a progressive facial nerve paralysis. We report a 20-year-old woman with an intracranial schwannoma originating from the greater superficial petrosal nerve that had wide extension into the pterygopalatine fossa. The motor facial nerve including the geniculate ganglion was not affected. The patient presented with vertigo, progressive hearing loss and mild facial nerve synkinesis but without a lacrimation deficit. The tumor was detected by computed tomography and magnetic resonance imaging. The schwannoma was completely removed using an intracranial, extradural middle fossa approach during which complete preservation of the motor facial nerve was possible. To our knowledge this is the first reported case of an isolated schwannoma of the greater superficial petrosal nerve without involvement of the motor facial nerve.