Hemispherectomy for intractable seizures: long-term results in 17 patients followed for up to 38 years

Seventeen patients who underwent hemispherectomy for intractable epilepsy between 1950 and 1971 were reviewed to evaluate outcome for seizure control and the development of late complications. Sixteen had complete resection and in one the frontal pole was preserved. The follow-up period was 19 to 38 years (mean 28 years). One patient was lost to follow-up review 10 years after surgery. Three patients had died but none of the deaths were related to the surgery or to epilepsy. Ten patients had no postoperative complications, and three developed late complications: two had elevated intracranial pressure with enlargement of the remaining lateral ventricle after 13 and 16 years, and one had recurrent bleeding into the cerebrospinal fluid after 6 years. All were treated surgically and have since remained well. Eight patients (47%) had no seizures after surgery and eight (47%) were almost seizure-free. It is concluded that classical hemispherectomy is an effective operation for control of some types of epilepsy. The late complications, which occurred in 17% of the cases in this series, can be successfully treated. This series presents the longest follow-up results after hemispherectomy reported to date.