Types of surgeries

• Lesionectomies (an example of a lesion would be a tumor).  This type of surgery involves operating on that particular area of the brain because it is causing the seizures.
• Non-lesional cases (when there is no visible lesion, but there is a particular electrical area that is clearly causing the seizures)
• Lobectomy: removing one lobe (temporal, frontal, parietal, occipital lobectomies) (see the appendix  to read more about each of these types of epilepsy)
• Hemispherectomy: removal of one hemisphere (half of the brain). This is done in some very dramatic situations in which the seizures are so devastating that is better to have functional deficits that the seizures. Diseases that may need to be treated with hemispherectomies include Sturge-Weber disease, Rassmussen’s disease.
Important: if the resection is done before age 7, for the most part, the function will be recovered. This is the result of something called “brain plasticity” (in very young brains, functions may shift to another part of the brain that is intact).  This translates into the patient has half of the brain removed, becomes paralyzed on one side, and after few months slowly may start recovering movement. Brain plasticity is not observed in adults.
• Corpus Callosotomy: this is a surgery for patients who cannot have a focal resection because there is no single focus. It works very well in patients who suffer seizures that produce loss of muscle tone and drops (“drop attacks”). Technically the surgery consists of splitting the brain in half by cutting the fibers (corpus callosum) that connect the two hemispheres.
• Multiple subpial transections: this type of surgery is mainly done in patients with “Landau-Kleffner” type of epilepsy. This is a type of epilepsy seen in children in which they lose the ability to speak.