More than 3 million people in the United States have epilepsy, a neurological disorder that causes recurring seizures. Of these, about 30% experience drug-resistant epilepsy, also known as refractory or intractable epilepsy, where standard anti-seizure medications are not effective.
Uncontrolled seizures can lead to physical injury and may increase the risk of sudden unexpected death in epilepsy (SUDEP). These ongoing seizures can also affect memory, emotions, driving ability, and employment.
The International League Against Epilepsy defines drug-resistant epilepsy as a condition where an individual does not achieve sustained seizure freedom after trying two appropriate medications, either alone or together.
For those whose epilepsy does not respond to medication or lifestyle changes, further evaluation at specialized centers is recommended. The Ohio State University Wexner Medical Center is designated as a Level 4 comprehensive epilepsy center and offers advanced diagnostic and treatment services for drug-resistant cases. Their team includes epileptologists, neurosurgeons, radiologists, neuropsychologists and other specialists who work together to determine the most effective treatment approach.
Diagnostic procedures at such centers typically include electroencephalogram (EEG), magnetic resonance imaging (MRI), single photon emission computed tomography (SPECT), and positron emission tomography (PET) scans. Sometimes these tests must be repeated for more accurate diagnosis. In certain cases, patients may undergo continuous video-EEG monitoring in an epilepsy monitoring unit to observe seizure activity under controlled conditions.
Once it is confirmed that medication alone is insufficient for controlling seizures, patients are informed about additional options like surgery or neuromodulation therapy. Surgical options depend on the location of seizure activity in the brain:
- Disconnection surgery involves cutting brain tissue responsible for seizures.
- Laser ablation targets and removes specific lesions causing seizures using minimally invasive techniques.
- Lesionectomy removes a lesion along with some surrounding tissue.
- Lobectomy involves removing part of the brain where seizures originate.
If surgery cannot safely remove the area causing seizures, neuromodulation therapies may be considered. These include deep brain stimulation (DBS), vagus nerve stimulation, and RNS neurostimulation—all approved by the U.S. Food and Drug Administration for treating drug-resistant epilepsy.
Research at Ohio State includes exploring non-invasive treatments such as sonic waves to remove epileptic foci. This emerging therapy could provide alternatives for patients who are not candidates for traditional surgical procedures or who experience tonic-clonic seizures characterized by loss of consciousness and body movements. While still under study, this method aims to control seizures without incisions or direct contact with the skull or brain.
