Intracranial EEG for Epilespy
Epileptic seizures occur when a group of neurons in the brain produce their own rhythmic, supercharged electrical activity, different from what the brain needs or wants. For example, seizures that occur in the motor areas of the brain result in repeated, uncontrollable jerking motions. When these electrical jolts come from lesions or structural abnormalities in the brain that can be seen on imaging scans, surgeons can often remove them and cure the problem if drug therapy has failed. The real challenge occurs when treatment doesn't help epileptic seizures that sprout from brains that look fine on imaging scans. Then, surgeons use electroencephalograph (EEG) probes, placed directly on brain tissue, to try to record changes in electrical activity in order to pinpoint nerve cells at fault. But this has been kind of like looking at a forest fire from a spaceship, says Mayo Clinic neurologist Gregory Worrell, M.D., Ph.D. By the time it can be seen, the electrical activity has spread into parts of the brain that have nothing to do with where the fire started. Now, Dr. Worrell, a specialist in epilepsy, and other researcher-physicians at Mayo Clinic, have found that using probes that pick up higher frequencies of rhythmic electrical oscillations than is traditional, does a better job of finding out where a seizure originates in the brain so that this tissue can be surgically removed.