Postinfectious Opsoclonus-Myoclonus Syndrome in a 41-Year-Old Patient-Visualizing Hyperactivation in Deep Cerebellar Nuclei by Cerebral [(18) F]-FDG- PET.

A 41-year-old woman presented with acute onset headache, vertigo, nausea, and gait disorder, initially interpreted as a common cold. Within 2 weeks, she developed a severe opsoclonus-myoclonus syndrome with truncal ataxia. Cerebrospinal fluid examination and serological findings suggested a recent infection with Coxsackie B3 virus. [(18) F]-FDG-PET proved to be the only imaging tool to identify the underlying pathology depicting hyperactivation in the vestibulo- and spinocerebellum as well as hyperactivation of the ocular muscles. At the clinical follow-up 4 months later, the patient's symptoms were considerably improved with only intermittent low-frequency opsoclonus. Corresponding PET findings were able to depict the response to therapy in the ocular muscles and the inferior vermis, whereas the deep cerebellar nuclei were still hyperactivated, however, to a lesser extent. This finding highlights the usefulness of functional/metabolic brain imaging to study the pathophysiology of this type of disorder.