Three‐dimensional magnetic resonance imaging of Baló‐like concentric lesion in multiple sclerosis

A 29-year-old Japanese woman had left hemiparesis with multiple lesions on brain MRI and positive oligoclonal IgG bands, leading to diagnosis of multiple sclerosis (MS). At 33 years, she developed dysarthria, and MRI showed a concentric lesion (Figure 1A–D). Three-dimensional fluid attenuated inversion recovery (FLAIR) MRI revealed a spherical concentric lesion (Video S1), slightly open on the periventricular side. Her symptoms improved following intravenous methylprednisolone therapy. After 1 year, the concentric lesion became unclear (Figure 1E,F). She has remained stable on natalizumab without relapse for 4 years. Baló's disease (BD) is a rare demyelinating disorder characterized by alternating concentric rings.1 BD usually shows multiple layers2 and often does not present clean circles,1 whereas the characteristics of concentric lesions in MS remain unknown. The concentric lesion in BD is speculated to develop simultaneously or as a sequential spread from a central core,1 and sometimes has an open-ring structure3 similar to our case. Although typical MS lesions tend to have a nonspherical shape,4 the concentric lesion in this case might have radially expanded from the lesion core and formed a spherical shape. The three-dimensional structure we present may contribute to a better understanding of the pathogenesis of concentric lesions in MS. We thank Edanz (https://jp.edanz.com/ac) for editing a draft of this manuscript. This work was supported in part by a JSPS KAKENHI grant (grant number JP23K06965). The authors report no disclosures relevant to the manuscript. Informed consent was obtained for this report. Further anonymized data are available upon reasonable request. Video S1 Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.