Surgery is most commonly done when tests show that seizures originate in a small, well-defined area in the temporal lobes or the frontal lobes of your brain. Surgery is rarely an option if one have seizures that start in several areas of the brain or if you have seizures originating from a region of the brain that contains vital brain functions.
During the procedure, your surgeon makes an incision in the scalp and removes a piece of the skull bone. He or she then cuts into or removes the area of the brain that's causing the seizures.
Although many people continue to need some medication to help prevent seizures after surgery, you may be able to take fewer drugs and reduce your dosages. In some cases, surgery for epilepsy can cause complications such as permanently altering your cognitive abilities. Talk to your surgeon about his or her experience, success rates and complication rates with the procedure you're considering.
Source for Epilepsy Surgery Info
Mayo Clinic
http://www.mayoclinic.com/health/epilepsy/DS00342/DSECTION=treatments-and-drugs
