Functional neuroimages of cortical myoclonus altered by levetiracetam in a patient with sialidosis.

Levetiracetam can suppress sialidosis-related myoclonus but its effects on cerebral metabolism warrant elucidation. In this report, fluorodeoxyglucose-positron emission tomography was conducted before and after levetiracetam in a sialidosis patient. By subtracting the drug "off" from "on" signals, regions of enhanced metabolism were shown to be allocated mostly in the bilateral fronto-temporal regions whereas regions of reduced metabolism were distributed mainly in the occipital areas. Imaging changes suggest that the effects of levetiracetam may be different in different brain regions. The drug may also elicit fronto-temporal inhibitory impulses to suppress the vigorous myoclonus in sialidosis.