POSITRON EMISSION TOMOGRAPHIC STUDY OF LATE-ONSET CRYPTOGENIC SYMPTOMATIC SEIZURES

Ten patients with epilepsy of unknown origin, starting after the age o f 50 years, and without clear evidence of cognitive decline were studi ed with positron emission tomography, using the steady state technique with O-15. Cerebral blood flow and oxygen metabolism were significant ly decreased in all cortical areas. No focal areas of hypometabolism w ere detected. Treatment with phenytoin did not influence the results. It is suggested that late-onset seizures could be the premonitory sign s of a progressive encephalopathy of unknown origin.