A 28-year-old woman was hospitalized with dysarthria and oro-mandibular and
upper limb dystonia. Approximately 8 years prior to the current admission,
the woman became severely hyponatremic due to traumatic subarachnoid hemor
rhage-related SIADH, Brain MRIs showed a signal increase in the central pen
s, thalamus and striatum on T2 weighted images compatible with central pont
ine and extrapontine myelinolysis. From a few months after that event, dyst
onia progressed slowly over the subsequent 8 years. We speculate that the p
articular damage chiefly to the myelin structures by myelinolytic process m
ay have caused an extremely slow plastic reorganization of the neural struc
tures. giving rise to progressive dystonia.