Acute disseminated encephalomyelitis: an MRI/MRS longitudinal study.

A clinical and radiologic diagnosis of acute disseminated encephalomyelitis was made in two children: a 6-month-old female who presented with focal seizures and thalamic and cerebral white matter lesions, and a 4.5-year-old male who presented with tremor and dystonia and had bilateral basal ganglia lesions, without evidence of active brain infection. Serial clinical and laboratory evaluations were supplemented by neuroimaging including routine magnetic resonance imaging and (1)H magnetic resonance spectroscopy. They were treated symptomatically, without using steroids or intravenous immunoglobulin, and both children recovered. Single voxel (1)H magnetic resonance spectroscopy data were acquired from the involved areas and from normal-appearing white matter. Abnormalities in N-acetyl-aspartate, choline, and lactate peaks were evident during the symptomatic phase, and persistence of low N-acetyl-aspartate was observed during recovery. These spectroscopic findings are consistent with neuropathologic findings of neuronal dysfunction, cellular membrane turnover, cellular infiltration, and metabolic stress in the acute phase, and with neuronal loss in the chronic phase.