Two cases of unilateral cortical fluid-attenuated inversion recovery-hyperintense lesions in anti-myelin oligodendrocyte glycoprotein-associated encephalitis with seizures (FLAMES)

Background

Myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) is a rare inflammatory disease of the central nervous system. Unilateral cortical fluid-attenuated inversion recovery-hyperintense lesions in anti-MOG-associated encephalitis with seizures (FLAMES) has recently been proposed as a subcategory of MOGAD. FLAMES is characterized by fluid-attenuated inversion recovery (FLAIR) imaging showing hyperintense cortical lesions in MOG-associated encephalitis with seizures.

Case Presentation

We herein report two cases of unilateral cortical FLAMES. The first case was a 29-year-old woman who developed headaches, fever, convulsions and right hemiparesis. Brain FLAIR magnetic resonance imaging (MRI) showed hyperintense cortical lesions on the left side. The second case was a 37-year-old women who developed headaches and fever. Brain FLAIR MRI showed hyperintense cortical lesions on the left side. Both cases were positive for anti-MOG antibodies in cerebrospinal fluid and serum, and were diagnosed with unilateral cortical FLAMES in MOGAD. Both patients were treated with intravenous methylprednisolone followed by oral corticosteroids, which improved MRI findings and clinical symptoms.

Conclusions

Both patients were diagnosed with MOGAD due to characteristic unilateral cortical encephalitis on brain FLAIR MRI. Unilateral cortical FLAMES is an important clue for the clinical diagnosis of MOGAD.