Neuromyelitis optica (NMO) is an inflammatory demyelinating disease of the central nervous system that causes severe optic neuritis and myelitis attacks. It tends to spare the brain early in the disease course. Characteristics of NMO that help to distinguish it from classical MS include:? (1)more severe optic neuritis and myelitis attacks; (2) prominent CSF pleocytosis (more than 50 WBC) that can be dominated by polymorphonuclear cells1-3;?(3)?lower frequency of CSF oligoclonal banding (15-30% compared with 85% in MS)1-3; and (4)?at disease onset, the brain MRI scan is normal or reveals nonspecific white matter lesions that do not meet MS MRI diagnostic criteria. During acute myelitis attacks, spinal cord MRI scans disclose a contiguous, longitudinally extensive lesion, centrally based in the cord and extending over three or more vertebral segments. MS lesions are more peripherally located in the cord and are less than one to two segments in length.
Read More: Neuromyelitis Optica (Devic’s Syndrome)