Temporal lobectomy: review of 100 cases with major hippocampectomy.

One hundred consecutive patients between 1961 and 1980, with temporal lobectomy including excision of half or more of the hippocampal formation, have been analyzed for degree of reduction of seizures. Thirty-nine percent have become and remained seizure free for follow-up period of 2 to 24 years (median 12 years). Another 24 patients achieved a marked reduction in seizure tendency as defined in the report and 25 showed a lesser degree of improvement. In fifteen patients no change in seizure frequency was recorded. Thus in this series of 100 patients, a complete or marked reduction of the seizure tendency was achieved in 63%.