Home > Encyclopedia of Surgery > Hemispherectomy

Definition

Hemispherectomy is a surgical treatment for epilepsy in which one of the two cerebral hemispheres, which together make up the majority of the brain, is removed.

Purpose

Hemispherectomy is used to treat epilepsy when it cannot be sufficiently controlled by medications.

The cerebral cortex is the wrinkled outer portion of the brain. It is divided into left and right hemispheres, which communicate with each other through a bundle of nerve fibers called the corpus callosum, located at the base of the hemispheres.

The seizures of epilepsy are due to unregulated electrical activity in the brain. This activity often begins in a discrete brain region called the focus of the seizure, and then spreads to other regions. Removing or disconnecting the focus from the rest of...