A Rare Occurrence of Demyelinating Lesions of Bilateral Trigeminal Nerves: An Atypical Presentation of Pediatric Multiple Sclerosis

Pontine trigeminal root entry zone is a typical, although uncommon, location for multiple sclerosis (MS) lesions to occur. Here, we present a 17-year-old girl with nausea, vomiting, and vertigo. Neurological examination was consistent with central nystagmus, positive Romberg's test, and left-sided hyperreflexia. Baseline magnetic resonance imaging fulfilled McDonald 2017 criteria for MS and showed T2-hyperintense and T1-hypointense bilateral demyelinating lesions at the intramedullary portion of the trigeminal root of the fifth nerve, with no contrast enhancement or restricted diffusion. Bilateral intrapontine trigeminal involvement is a rare finding in MS, as well as the combined central and peripheral demyelination. Furthermore, very limited information and cases have been described in pediatric patients.