Neuromyelitis optica (NMO) and neuromyelitis optica spectrum disorders (NMOSD) have been recognized in the last 15 years according to its clinical and laboratory findings, MRI and anti-aquaporin-4-IgG antibodies discovery, as a separate nosological entity, different from multiple sclerosis. Electrophysiological examination including evoked potentials (EPs) is not a part of formal NMO/NMOSD criteria.
In the past ten years, multiple studies appeared, analyzing the contribution of EPs in the diagnostics, disease monitoring, and prognosis in NMO/NMOSD. The actual survey focuses on the most important one.
Most of the studies, though retrospective and cross-sectional, show that the findings are more homogenous in the Aphro-American and Asian population than in the Caucasian one. The most often seen abnormality was the absence of EPs, amplitude reduction of VEP in optic neuritis, and MEP and/or SEP in longitudinal extension transverse myelitis.
These findings reflect more severe axonal loss than demyelination in NMO/NMOSD. In the Caucasian population, the findings in EPs might be more heterogeneous, with a higher frequency of mild latency increase of EPs and less amplitude reduction or EP absence.
The data from many studies point to a high correlation of the abnormity pattern in the case of the first attack of optic neuritis and/or longitudinal extension transverse myelitis and the next rebound of the disease. Although the multimodal EPs are not a part of formal NMO/NMOSD diagnostic criteria, their role in the diagnostics, monitoring disease course and prognosis of the NMO/NMOSD, is indubitable.
Most of the published studies are cross-sectional, opened and retrospective, and therefore new prospective, randomized, and multicentre studies are invited.