Early bilateral splenium lesions with subsequent progression in Neuromyelitis Optica patients

Background

Neuromyelitis Optica (NMO) is a central nervous system (CNS) demyelinating disease. However, very little is known about callosal lesions in NMO. In addition, extensive splenic involvement as the first radiological finding is unusual and poorly described.

Case Presentation and Report

A female in her 30′s and a male in his 50′s were presented with lower limb weakness and blurry vision. MRI of the brain revealed focal lesions in the lateral splenium of the corpus callosum. However, over the next two months, symptoms become worsened. Repeated brain MRI showed a further progression of the splenium lesion. Plasma exchange resulted in clinical improvement and rituximab was used to maintain the clinical stability.

Conclusion

Extensive splenium lesion suggests NMO rather than MS, and this pattern can take up to two months to establish. This pattern of splenium involvement can be preceded by bilateral lateral splenium involvement in the early phase. Furthermore, in the acute stage, these patients require aggressive and prompt treatment with plasma exchange rather than steroid to prevent further deterioration.