Concentric ring of Balo

Balo's Concentric Sclerosis, is considered a rare variant of multiple sclerosis (MS), is characterized by a lesion consisting of rings of demyelination alternating with rings of intact myelin. Lesions have been observed in the spinal cord, cerebellum, brain stem, optic chiasm, and cerebral hemispheres.2 BCS is thought to be slightly more prevalent among males than among females, and to be particularly prevalent among younger men.3 Traditionally, BCS has been considered to be a rapidly fatal disease. With the advent of MRI, patients like the individual described in this Case Study have been diagnosed early, received treatment, and survived for months or years. These results imply that some cases of BCS might have a mild course, and cases that could have been effectively treated but previously remained unrecognized are now being discovered. A classification scheme for BCS has been proposed that defines the disease into the following three subtypes: a self-limited, monophasic illness; relapsing–remitting demyelination; and the classically described, primary rapidly progressive course. Nature Clinical Practice Neurology (2007) 3, 349-354