Spinal cord lesions in patients with neuromyelitis optica: a retrospective long-term MRI follow-up study

Neuromyelitis optica (NMO) is characterised by a particular pattern of the optic nerves and the spinal cord. Long-term MRI follow-up studies of spinal NMO lesions are rare, or limited by short observation periods. In nine patients with definite NMO or recurrent longitudinally extensive transverse myelitis (LETM) with NMO-IgG serum antibodies, repeated MRI examinations of the spine were carried out over a period of up to 11 years and evaluated regarding the changes over time in this retrospective study. In eight patients spinal cord lesions were located centrally, involving the grey and white matter. In the first examination after clinical onset changes resembled a stroke of the anterior spinal artery in two patients. Symmetrical signal alterations within the grey matter were observed. In one patient this pattern was transient, but it remained in the other. During the chronic stage, either a variable degree of spinal cord atrophy and high signal alterations, or almost complete remission of the lesions, was observed. Spinal MRI of patients with NMO myelitis can resemble a stroke. MRI of acute NMO stages did not allow a prediction of the clinical outcome. To a variable degree, NMO left behind typical defects which correlated with the clinical outcome.