Presentation
Subacute progressive left-side weakness not preceded by a viral infection.
Patient Data

















The imaging shows white matter demyelinating lesions. The biggest lesion in the right centrum semiovale presents the most characteristic imaging appearance, showing irregular concentric areas alternating isointense and hyperintense T2 signals and a characteristic “bull’s-eye” appearance. On diffusion-weighted images, it presents with restriction areas in the outer ring, and after contrast injection, non-significant enhancement is shown.
Case Discussion
Serum aquaporin-4 was negative.
CSF examination revealed the absence of IgG oligoclonal bands.
We started treatment with a bolus of 1 g of methylprednisolone daily. The patient improved favourably to treatment by the third day and was discharged after 5 days due to symptom resolution.
Balo concentric sclerosis is a rare and severe monophasic demyelinating disease, considered a subtype of multiple sclerosis, appearing as a rounded lesion with alternating layers of increased and reduced signal, giving it a characteristic 'bull's eye or 'onion bulb' appearance.