Objective and importance: The presentation, diagnosis, and treatment are described for a patient with a giant ependymoma involving the right cerebellopontine angle extending into the cavernous sinus. This case presents the unusual occurrence of a large extra-axial intracranial ependymoma and is the first reported case of cavernous sinus extension of this tumor.
Clinical presentation: The patient was a 22-year-old woman who presented with a 3-day history of generalized headache and right-sided facial droop. Magnetic resonance imaging revealed a nonhomogeneously enhancing cystic mass that was primarily in the posterior fossa with significant supratentorial extension and no apparent intra-axial or intraventricular involvement.
Intervention: Gross total resection of this mass was achieved via two-staged resections using an initial presigmoid transpetrous, transtentorial approach and a subsequent pterional craniotomy. Pathological evaluation confirmed the diagnosis of ependymoma, and adjuvant radiation therapy to the resection bed was administered.
Conclusion: Ependymomas can present as entirely extra-axial intracranial masses and rarely may involve the confines of the cavernous sinus.