New Onset Nystagmus in a Patient with Multiple Sclerosis.

CASE PRESENTATION: A 50-year-old male with a history of multiple sclerosis with dizziness and nystagmus presented to the emergency department. On physical exam, nystagmus was noted. Computed tomography of the head without contrast was obtained showing a low density in the left frontal lobe. During admission, magnetic resonance imaging (MRI) findings were consistent with Balò's concentric sclerosis.

DISCUSSION: Balò's concentric sclerosis is a rare, inflammatory demyelinating disease, often considered to be an infrequent variant of multiple sclerosis with alternating rings of healthy myelin and demyelination leading to pathognomonic findings of concentric lamella on T2 or contrast-enhanced T1 MRI imaging.