Epilepsy of late onset

Abstract

A follow-up study is presented of 141 patients with epilepsy of onset after the age of 20 who were seen at the National Hospital for Nervous Diseases, London. Only 16 have been shown to have cerebral tumors. Of the others, 56 are believed not to have tumors on the basis of anatomic investigations by air encephalography or arteriography or both plus a follow-up period of not less than 3 years; 20 other patients are believed not to have tumor on the basis of a 15 year follow-up alone. Additional tumors may yet be found among the remaining 49, but reasons are presented why these should not be numerous nor invalidate statistical comparison of the 2 groups. The following circumstances significantly increase the likelihood of tumor to 28 to 50% and warrant contrast roentgenogram study: Abnormal physical neurologic signs, the best single criterion; focal motor seizures or seizures with focal sensory aura; focal abnormality in the eeg (rare in this study unless the seizures were also focal); initial onset of fits in a patient over 50 years old. Anatomic investigation is ordinarily not warranted in epileptic patients of adult onset who do not satisfy at least one of the above cri -teria[long dash]provided a satisfactory future follow-up can be made. Even epilepsy of more than 10 years'' duration may be based on cerebral tumor[long dash]without the tumor killing the patient or being obvious. Failure to find abnormal physical neurologic signs in a patient who has been having fits for as long as 3 years, however, is a strong argument against the presence of a tumor, unless the seizures or the eeg''s are focal or the patient is more than 50 years old. Even a normal air encephalogram at initial investigation does not rule out the possibility of tumor, and this diagnosis was made subsequently in 2 patients who were reinvestigated after a year''s time because signs and symptoms had progressed. The need for follow-up is thus not obviated by any initial study.