Gamma Knife Radiosurgery for Trigeminal Neuralgia Caused by a Cavernous Malformation: Case Report and Literature Review

Case Report: Recurrent pediatric cavernous malformation of the trigeminal nerve

Background

Most cavernous malformations (CM) usually involve the parenchyma and rarely occur in cranial nerves. Recurrence of CM associated with cranial nerves after surgical resection has not been previously reported.

Case description

This paper describes the case of an 11-year-old girl who presented with left otalgia and headache because of a left trigeminal cavernous malformation. She underwent radical resection via a left retrosigmoid approach while sparing the trigeminal nerve. Surveillance imaging at 18 months demonstrated recurrence along the length of the trigeminal nerve into Meckel's cave with significant extension into the middle cerebellar peduncle. Subsequent re-operation via an extended middle fossa approach with anterior petrosectomy enabled complete resection with division of the trigeminal nerve. Postoperatively, she had a transient left facial paresis, and right hemiparesis that resolved within 48 h.

Conclusion

This case highlights the importance of close postoperative surveillance in CM associated with cranial nerves as recurrence after nerve-sparing resection is possible. Surgical treatment due to the morphology of significant recurrence required the use of a complex skull base approach through a new corridor to achieve optimal clinical outcome.

Trigeminal neuralgia caused by cavernoma: A case report with literature review

Cavernoma is the second most common cerebrovascular lesion. Cavernoma involving the cranial nerves is very rare. Only 15 cases of cavernoma presenting with trigeminal neuralgia (TN) have been previously reported. Here, we report a rare case of cavernoma manifesting with TN. A young female patient with a 15-day history of right-sided lancinating pain in the face, difficulty in opening the mouth, and hearing dysesthesia. Magnetic resonance imaging (MRI) revealed a well-demarcated lesion in the cerebellopontine angle related closely to the root of the trigeminal nerve. The initial impression was that of a neurinoma. The lesion was surgically resected via the retrosigmoid approach, postoperative pathological analysis confirmed the diagnosis of cavernoma, and the patient's pain and difficulty in opening the mouth resolved completely. We presented the 16^th documented case of cavernoma with TN. Although cavernoma involving the trigeminal nerve is extremely rare, this diagnosis should be taken into consideration when a lesion in the cerebellopontine angle is detected on MRI, and the clinical manifestation is consistent with that of secondary TN. Specialized MRI sequences, such as susceptibility weighted imaging (SWI), gradient echo T2, and constructive interference in steady-state (CISS)-weighted imaging, aid in establishing the diagnosis. Resection via craniotomy may be the primary management strategy for cavernoma causing TN. In addition, gamma knife radiosurgery (GKRS) and percutaneous balloon compression (PBC) may ameliorate the pain to some extent.

An isolated cavernous malformation of the sixth cranial nerve: A case report and review of literature

Background

Isolated cavernous malformation (CM) of the abducens nerve has not been reported in the literature. Herein, the authors address the clinical importance of these lesions and review the reported cases of CM from 2014 to 2020.

Case Description

A 21-year-old man presented with binocular diplopia and headache from 2 months before his admission. The neurological examination revealed right-sided abducens nerve palsy. The brain MRI revealed an extra-axial pontomedullary lesion suggestive of a CM. The lesion was surgically removed. During the operation, the abducens nerve was resected considering the lesion could not be separated from the nerve and an anastomosis was performed using an interposition nerve graft and fibrin glue. Pathological examination of the resected lesion revealed that it was originated from within the nerve. The patient's condition improved in postoperative follow-ups.

Conclusion

Surgical resection of the cranial nerves CMs is appropriate when progressive neurological deficits are present. If the lesion is originated from within the nerve, we suggest resection of the involved nerve and performing anastomosis. Novel MRI sequences might help surgeons to be prepared for such cases and fibrin glue can serve as an appropriate tool to perform anastomosis when end-to-end sutures are impossible to perform.