In this review, we address the 4 major classes of demyelinating disease: multiple sclerosis (MS), neuromyelitis optica (NMO), anti-MOG-associated encephalomyelitis (MOG-EM), and acute disseminated encephalomyelitis (ADEM), and discuss their prevalence, demographics, clinical diagnosis workup, and imaging features in the Indonesian population, as well as the challenges we face in their diagnosis and therapeutic approach. The gene discussed is MOG; the disease is myeloid sarcoma.