An intracranial odyssey: pediatric ganglioneuroma arising from the trigeminal ganglion: a case report and review of the literature.

Background: Ganglioneuroma represents an uncommon benign tumor arising from the sympathetic nerves, and its development from the fifth nerve is an infrequent entity. Few ganglioneuromas arising from the fifth nerve have been discussed in literature. The authors describe the second pediatric ganglioneuroma arising from the fifth nerve.

Case presentation: A 7 year-old Asian male suffering from left-sided facial paresthesia, accompanied by several episodes of complex seizures over the past 2 years, presented to our clinic. The patient also complained of sudden unconsciousness and concurrent upward gaze lasting less than a minute. A brain computed tomography scan and magnetic resonance imaging revealed an isodense lesion containing focal calcifications measuring 31 × 28 mm and a solid mass extending from the pontine surface to Meckel's cave, probably originating from the fifth nerve or its root entry zone. The lesion was mildly hypointense on T1-weighted sequences and hyperintense on T2-weighted and fluid attenuated inversion recovery sequences. Gadolinium injection revealed only minimal heterogeneous enhancement. Histopathologic and immunohistochemical findings were consistent with ganglioneuroma. A lateral approach via retrosigmoid incision and suboccipital lateral craniectomy toward the cerebellopontine angle was performed under neuromonitoring supervision, and the postoperative period was uneventful.

Conclusion: Although ganglioneuroma arising from the fifth nerve is an extremely rare entity, it should be considered when diagnosing lesions in Meckel's cave or the cerebellopontine angle cistern.