Delayed-onset dystonia following recovery from central pontine myelinolysis.

We report on a 47-year-old female patient with Sheehan's syndrome who developed delayed-onset dystonia following recovery from central pontine myelinolysis. The dystonia was observed in the head, neck and limbs during active movement. MRI scan demonstrated a discrete lesion in the central pons without involving the basal ganglia. The action dystonia was markedly improved by giving trihexyphenidyl. The patient showed that generalized dystonia can be induced by an isolated pontine myelinolysis. There have been four other cases reported in the literature. On reviewing all five cases, we conclude that delayed-onset dystonia following central pontine myelinolysis usually presents with generalized action dystonia and has a beneficial response to trihexyphenidyl.