T2/FLAIR hyperintensity about the right lateral ventricle trigone, temporal horn and occipital horn, with further signal abnormality involving corpus callosum and periaqueductal grey matter. There are no lesions running perpendicular to the lateral ventricles, and no deep or subcortical white matter lesions.
This distribution of intracranial lesions corresponds to areas of high expression of the aquaporin 4 receptor that is implicated in the immunopathogenesis of NMO. There are no stereotypical 'Dawson's finger' or juxtacortical lesions that are common in multiple sclerosis.