AQP4 and optic neuritis: Additional test includes magnetic resonance imaging (MRI) of the brain and optic nerves, optical coherence tomography (OCT), cerebrospinal fluid (CSF) analysis, and serum antibody testing for AQP4‐IgG and MOG‐IgG and may include visually evoked potentials.2, 7, 8 Typical optic neuritis is a clinical diagnosis, which can be made based on the medical history and ophthalmological findings alone, especially as advanced diagnosis tools are not equally accessible in all areas of the world.