Types of Epilepsy Surgery
If your seizures cannot be controlled with medications, surgery may offer the best opportunity for you to achieve seizure freedom. Approximately 60 to 70 percent of patients may become seizure-free after resective surgery, depending on the type of seizure, its origin in the brain, and what caused its development. However, surgery is not an option for everyone with epilepsy. It is only effective with certain types of seizures. If we can pinpoint the origin of your seizures within the brain, what we call the “seizure focus,” and if the region from which it arises can be safely removed, surgery may work for you. Our comprehensive approach to pre-surgical evaluation helps find where the seizures begin. We perform sophisticated, non-invasive source localization, which minimizes the need for open surgical procedures during pre-surgical evaluation.
At the University of Chicago Medicine, we perform several different types of surgeries to treat epilepsy. They include:
- Focal resection
- Stereotactic epilepsy surgery
- Corpus callosotomy
- Subpial transection
This procedure involves removing the portion of the brain where your seizures originate. For example, neurosurgeons remove a portion of the temporal lobe in patients with temporal lobe epilepsy. At the University of Chicago Medicine, we use comprehensive, non-invasive technologies to help localize the seizure origination site and determine if there is more than one origination site. This is important because focal resection is only effective only if seizures consistently originate from one location in the brain.
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Stereotactic epilepsy surgery is minimally invasive and employs a three-dimensional coordinate system applied to the brain by attaching a frame to the head. With the help of MRI/CT/PET and fast computers, any point in the brain can be safely reached with sub-millimetric precision. In combination with different technologies, the following approaches are used at the University of Chicago Medicine, offering minimally invasive ways to provide long-term seizure control and avoid the risks associated with open brain surgery:
- MRI-guided stereoelectroencephalography (SEEG) and laser ablation technology can be used safely and effectively in some patients with a single, well-defined seizure focus, such as medial temporal lobe epilepsy and hypothalamic hamatomas. Our epilepsy team was the first in Illinois to offer this breakthrough approach to treating epilepsy. During a SEEG procedure, surgeons place electrodes into the brain to precisely locate the seizure focus. Next, the surgeon uses a sophisticated laser applicator to carefully destroy the seizure source with pinpoint accuracy.
- Radiosugery, which can aim radiation in a single treatment session to destroy an epileptic focus using a linear accelerator
- Radiofrequency lesioning, which can be applied to thermally destroy an epileptic focus via a small probe.
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A hemisphrectomy is a treatment we don’t often recommend. It involves removing almost all of one hemisphere, or side, of the brain. It can be a very successful procedure, but it is never a first option for treatment. We usually only perform it in newborns and children whose brains are capable of compensating for the removal of so much tissue.
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The goal of corpus callosotomy surgery is to interrupt the pathway by which seizures spread. If the pathway is interrupted, the seizure cannot spread to other parts of the brain. This surgery does not remove parts of the brain. Instead, the surgeon will cut the large bundle of fibers that connect the two brain hemispheres. This fiber bundle is called the corpus callosum. There are two types of corpus callosotomy procedures. One cuts only part of the fiber bundle (a partial callosotomy), and the other severs the entire bundle (a complete callosotomy).
The University of Chicago Medicine was the first in Illinois to convert open callosotomy to a stereotactic procedure via a single burr hole. With this technique, the corpus callosum is stereotactically targeted and then cut with a small electrode applying radiofrequency current.
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Other similar techniques, such as multiple subpial transections, can also be considered if a seizure focus overlaps with areas of important brain functions such as language, motor skills and sensory ability. Multiple subpial transections is a surgical procedure we sometimes use for patients who have well-localized epileptogenic areas that can’t be resected because they are too important to overall brain function. The goal of the procedure is to sever fibers that are likely responsible for spreading seizure activity while preserving the fibers that control the necessary brain functions. This technique allows a small area of the brain to seize, but does not allow the seizure to spread and cause overt symptoms.
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- Treatment Options for Seizures and Epilepsy
- Types of Epilepsy Surgery