Cerebral Cortex Involvement in Neuromyelitis Optica Spectrum Disorder

Area of Science:

• Neuroimmunology
• Neuroimaging
• Neurology

Background:

• Cerebral cortex involvement is uncommon in neuromyelitis optica spectrum disorder (NMOSD), unlike in multiple sclerosis.
• Anti-aquaporin-4 (AQP4) antibody-seropositive NMOSD patients are the focus of this investigation.

Purpose of the Study:

• To investigate the occurrence and characteristics of cerebral cortex lesions in anti-aquaporin-4 (AQP4)-antibody-positive NMOSD patients.
• To utilize conventional brain magnetic resonance imaging (MRI) for detecting cortical involvement.

Main Methods:

• Retrospective analysis of demographic, clinical, and MRI findings from 215 anti-AQP4 antibody-positive NMOSD patients.
• Consensus identification of abnormal cerebral cortex lesions by a neuroradiologist and two neurologists.

Main Results:

• Brain lesions were observed in 74% of patients with follow-up MRI.
• Cortical lesions were identified in 3.1% (6 out of 194) of patients with follow-up MRI.
• Five of the six patients with cortical lesions were female; three showed leptomeningeal enhancement, and five were untreated at presentation.

Conclusions:

• Cortical involvement, though rare, is a potential manifestation in NMOSD.
• Leptomeningeal enhancement is frequently associated with these cortical lesions.
• Inadequate immunosuppressant treatment may be a contributing factor to the development of cortical lesions in NMOSD.