Concurrence of high-grade brainstem glioma and multiple sclerosis.

A 50-year-old woman presented with subacute onset of headache, tinnitus, vertigo, emesis, diplopia and right-sided limb paresthesias. She had a known diagnosis of relapsing remitting multiple sclerosis (MS) but had remained stable after her first attack seven years earlier. She was on no disease modifying agents or immunosuppressants. Examination disclosed right gaze-evoked nystagmus, partial right sixth nerve palsy, right facial hypoesthesia, left-sided hyperreflexia and spasticity, and an ataxic gait. Magnetic resonance imaging (MRI) demonstrated a ponto-medullary-cervical lesion that, on review, was present six years prior (Figure 1). Given the patient’s history and the radiographic appearance of the lesion, the differential diagnosis included a demyelinating plaque or a brainstem neoplasm. The patient improved clinically with high-dose steroid therapy and was discharged home asymptomatic. Biopsy was deferred given the lesion location. Three months after discharge, she had