Oculomotor Nerve Schwannoma: A Case Report

Schwannomas account for about 8% of intracranial tumors and 90% are vestibular schwannomas. Oculomotor schwannoma without neurofibromatosis is extremely rare. A 41-year-old female presented with complaints of blurred vision, and the neurologic examination revealed afferent pupillary defect and decreased visual acuity of the left side. Brain magnetic resonance image showed an extra axial mass in the left superior orbital fissure. The patient underwent major surgery via the fronto-temporal approach. The tumor originated from the oculomotor nerve and was subtotally removed under microscopic surgery. The pathological findings confirmed the tumor as a schwannoma. After surgery, ptosis and medial gaze limitation of the left eye was detected, but the symptoms improved gradually.

Olfactory Schwannoma: Case Report

Intracranial schwannomas preferentially arise from the vestibular branch of the eighth nerve, and rarely from the trigeminal nerve, facial nerve, and lower cranial nerves. Anterior cranial fossa schwannomas are extremely uncommon and few details about them have been reported. The patient was a 39-year-old woman whose chief complaints were anosmia and frontal headache for 2 years. The gadolinium (Gd)-enhanced magnetic resonance imaging (MRI) showed an extra-axial mass from ethmoid sinus to right frontal base region near the midline, with solid enhancement in lower portion and multicystic formation in upper portion. The tumor was totally resected via basal subfrontal approach. At operation, the tumor had cystic portion with marginal calcification and the anterior skull base was destructed by the tumor. The olfactory bulb was involved, and the tumor capsule did not contain neoplastic cells. The histopathological diagnosis was schwannoma. We report a rare case of anterior cranial fossa schwannoma with literature review.