The signs and symptoms of NMOSD depend on the neurologic structures the disease affects, and, to some extent, the antibodies involved. Signs and symptoms usually follow a relapsing and remitting course, but occasionally can be progressive (monophasic). Deficits can be temporary or permanent, the latter especially in the absence of treatment. The most common initial manifestation of the disease is inflammation of the spinal cord (myelitis). Myelitis causes spinal cord dysfunction, which can result in muscle weakness, paralysis in the limbs, lost or reduced sensation, spasms, loss of bladder and bowel control, or erectile dysfunction. The myelitis can be transverse, affecting an entire cross-section of the spinal cord, and showing bilateral symptoms. The second most common initial manifestation of the disease is inflammation of the<unk> nerve and/or<unk> chiasm <unk> neuritis, ON). ON may lead to varying degrees of visual impairment with decreased visual acuity, although visual field defects, or loss of color vision, may occur in isolation or prior to formal loss of visual acuity. Compared to idiopathic ON and ON due to multiple sclerosis (MS), ON due to NMOSD more often results in severe visual loss at onset, with bilateral involvement, and permanent visual deficits. Classically, NMO included only symptoms of myelitis and ON. However, with the discovery of disease-causing antibodies, a broader<unk>  of disease manifestations has been grouped with NMO into the diagnosis of NMOSD. Less commonly than the spinal cord and<unk> nerve, NMOSD can affect the brain stem. Lesions in the brain stem or upper cervical spinal cord can cause respiratory insufficiency. Lesions in the area postrema of the medulla oblongata can cause vomiting or hiccups, as well as pain and tonic spasms. Additional brain lesions are common but often asymptomatic (though cognitive deficits, as well as depression, may be underdiagnosed sequalae). Lesions may also affect the diencephalon, mostly in Aquaporin-4–Immunoglobulin-G (AQP4-IgG) NMOSD.
Neuromyelitis optica spectrum disorder
Alexander disease
Corneal-cerebellar syndrome
Leber's hereditary optic neuropathy
Subacute myelo-optic neuropathy
Canavan disease
Grinker myelinopathy
Toxic and nutritional optic neuropathy