Transient global amnesia and epilepsy. Electroencephalographic distinction
J. W. Miller, T. Yanagihara, R. C. Petersen and D. W. Klass
Electroencephalographic recordings were obtained during 13 episodes of
transient global amnesia in 13 patients. Eight were entirely normal; none
showed seizure discharges or other epileptiform activity.
Electroencephalographic recordings were also obtained after 103 episodes of
amnesia in 96 patients with transient global amnesia (TGA) alone, five
patients who had both TGA and epilepsy independently, and three patients
with amnesia related to epilepsy. The majority (60.8%) of waking records
were normal during or after episodes of TGA. Mild or moderate and nonfocal
abnormalities were found in a minority. Genuine epileptiform activity was
observed only among patients who had seizure disorders. Amnestic episodes
attributable to seizures were more brief and more apt to be repeated than
TGA and usually responded to anticonvulsant drugs. Differentiation of TGA
from epilepsy is essential for appropriate management.