Trigeminal schwannoma presenting as a gelastic seizure: no laughing matter

Management of non-vestibular schwannomas in adult patients: a systematic review and consensus statement on behalf of the EANS skull base section Part II: Trigeminal and facial nerve schwannomas (CN V, VII)

BACKGROUND

Non-vestibular schwannomas are relatively rare, with trigeminal and jugular foramen schwannomas being the most common. This is a heterogenous group which requires detailed investigation and careful consideration to management strategy. The optimal management for these tumours remains unclear and there are several controversies. The aim of this paper is to provide insight into the main principles defining management and surgical strategy, in order to formulate a series of recommendations.

METHODS

A task force was created by the EANS skull base section committee along with its members and other renowned experts in the field to generate recommendations for the surgical management of these tumours on a European perspective. To achieve this, the task force performed an extensive systematic review in this field and had discussions within the group. This article is the second of a three-part series describing non-vestibular schwannomas (V, VII).

RESULTS

A summary of literature evidence was proposed after discussion within the EANS skull base section. The constituted task force dealt with the practice patterns that exist with respect to pre-operative radiological investigations, ophthalmological assessments, optimal surgical and radiotherapy strategies, and follow-up management.

CONCLUSION

This article represents the consensually derived opinion of the task force with respect to the treatment of trigeminal and facial schwannoma. The aim of treatment is maximal safe resection with preservation of function. Careful thought is required to select the appropriate surgical approach. Most middle fossa trigeminal schwannoma tumours can be safely accessed by a subtemporal extradural middle fossa approach. The treatment of facial nerve schwannoma remains controversial.

Ancient Schwannoma affecting the intracranial portion of the trigeminal nerve: A case report

Background:

Ancient trigeminal schwannomas are extremely uncommon benign tumors. Such tumors are longstanding, slow growing and may demonstrate seemingly malignant features irrespective of its benign nature. The tumor may involve the trigeminal nerve root, the trigeminal ganglion, or any of its peripheral branches. Its clinical presentation may include trigeminal neuralgia, blurry vision, diplopia, or even seizures. Surgical excision is the mainstay of treatment with definite diagnosis only by histopathology.

Case Description:

We described a case of a 35-year-old female presenting with recurrent episodes of generalized seizure and left-sided weakness. Brain imaging showed a right temporal space occupying lesion. Results of histopathology were consistent with trigeminal schwannoma associated with ancient histopathological changes. Complete tumor excision was achieved by a two-stage craniotomy, which led to the patient’s condition to dramatically improve.

Conclusion:

Ancient trigeminal schwannomas are easily diagnosed through histopathology and result in favorable clinical outcomes after total microscopic surgical excision. A high suspicion index of ancient schwannoma diagnosis should be derived from the patient’s presenting clinical picture and the classical findings derived from neuroimaging.