Microneurosurgical treatment under the guidance of neuroendoscopy for an intracranial optic nerve Schwannoma: A case report.

Rationale: Optic Schwannoma is rarely observed clinically as optic nerve had anatomically impossibility for the location of Schwannoma. However, several reports described the established cases of optic Schwannoma, of which the locations were in orbit or within optic canal. The occurrence of optic Schwannoma intracranially has been not reported. Patient Concerns: A 60-year-old female complained of visual impairment in the right eye and the frequent headache and the dizziness over 2 years with unknown reasons. The result of magnetic resonance imaging (MRI) showed a round, well-circumscribed, heterogeneously enhancing signal with cystic change displayed on the right suprasellar cistern. Diagnoses: Intracranial optic Schwannomas. Interventions: The patient accepted microneurosurgery assisted by endoscopy. We observed a gray and yellow lesion located near the right anterior clinoid process with a mid-sized cyst. And there was a vague boundary between the tumor and the right optic nerve which was compressed by the tumor. Optic chiasm and left optic nerve were also compressed. Meanwhile, the tumor had also adhesion to the right anterior cerebral artery (ACA). Outcomes: After the tumor was totally resected, the patient had satisfactory recovery. Lessons: We reported an intracranial optic Schwannoma removal with the lateral supraorbital keyhole approach assisted by neuroendoscopy. Intracranial optic Schwannoma was rarely seen clinically. Neuroendoscopy imaging suggested the close relationship between the tumor and ACA, supporting vasculature-origin hypothesis for the optic Schwannoma.