Cincinnati Children’s is one of only a few dedicated pediatric epilepsy surgery programs in the United States to offer all of the diagnostic tests and tools needed to evaluate children with epilepsy. As a result of our advanced technologies and our team’s experience and expertise, patients whose condition might be considered inoperable elsewhere can undergo epilepsy surgery at Cincinnati Children’s.
Epilepsy surgeries take place in the hospital’s stereotactic surgical suite, or BrainSUITE. There, imaging technologies allow the surgical team to further pinpoint the seizure focus and see how close it is to primary language, motor and sensory areas of brain. This helps the surgeon avoid critical areas while navigating to the seizure focus, and remove the diseased part of the brain safely. This technology allows our neurosurgeons to treat patients who would once have been considered inoperable because of where their seizure focus was located.
Cincinnati Children’s was the first pediatric hospital in the world to use the BrainSUITE concept in the operating room, with an integrated neurosurgical microscope, high-definition screens and a specialized bed with comprehensive magnetic resonance imaging capabilities.
Who is a Candidate for Epilepsy Surgery?
Children with epilepsy whose seizures have not responded to two or more anti-epilepsy medications may need surgery. Only a small percentage of children with epilepsy (5-10%) undergo surgery. The goal of surgery is to dramatically reduce the severity and frequency of seizures and, when possible, eliminate them altogether.
What is the Evaluation Process for Epilepsy Surgery?
During your initial visit, our team will talk to you about your child’s medical history related to epilepsy, including past medications and treatments. We will compile a complete medical, family and seizure history for your child, and review any previous testing your child has had done for epilepsy, such as past EEGs or MRIs. After completing questionnaires regarding your child’s quality of life and medication side effects, you will meet with our genetic specialist, who may recommend testing.
Tests and Imaging
After the initial visit, we will perform an extensive evaluation and non-invasive testing. This helps create a detailed map of your child's brain, find out where the seizures are starting and how they are spreading, and more. Tests can include:
Video Electroencephalogram (VEEG) and Geodesic EEG
Video Electroencephalogram (VEEG) and Geodesic EEG are noninvasive tests that record the electrical activity in the brain by using electrodes attached to the scalp.
Magnetoencephalography (MEG) monitors the electrical activity of the brain, using magnets to accurately detect the seizure focus. It is one of the newest non-invasive tests available for studying epilepsy and brain function.
During a MEG test, the child lies still with his or her head inside a helmet that contains hundreds of sensors, and may be given a light sedative to cause drowsiness. During the scan, the patient may be asked to perform a specific task, such as reading, looking at pictures or pressing buttons. MEG scans show which area of the brain is active while these tasks are being performed, providing doctors with a detailed understanding of a child’s brain activity.
MEG and video electroencephalography (VEEG) both measure brain activity. However, MEG measures magnetic fields and brain activity produced by neurons, while an EEG records electrical activity in the brain. MEG is a more accurate testing method than VEEG.
Magnetic Resonance Imaging (MRI)
Magnetic Resonance Imaging (MRI) is an imaging test that uses a magnetic field and radio waves to produce detailed images of the brain and the brain stem.
Functional Magnetic Resonance Imaging (fMRI)
A functional MRI (fMRI) uses a safe magnetic field to create images of the brain while it is at work. An fMRI can show doctors which parts of the brain are involved in different mental processes, such as language, movement and vision. Test results help doctors plan surgery by identifying where the brain’s critical structures are located.
The test takes place in the MRI scanner. During the test, the child usually is awake and asked to participate in tasks, such as looking at a picture or listening to music. fMRI software maps where brain activity occurs when the child is performing these tasks.
Positron Emission Tomography (PET)
Positron emission tomography (PET) is a type of test that measures metabolic activity within the brain cells. PET can show biochemical changes taking place in the brain that can cause seizures.
During the test, the child lies on a table that slides into the PET scanner. A small amount of glucose-based material is inserted into an intravenous line. Once the material reaches the brain, the PET scanner shows where cell activity is (and isn’t) taking place. Decreased cell activity (or “cold spots”) suggests possible areas of seizure activity.
Single Photon Emission Computed Tomography (SPECT)
Single photon emission computed tomography (SPECT) helps pinpoint the area causing seizures by showing where there is increased blood flow in the brain. There are two kinds of SPECT scans:
- Ictal SPECT: a procedure done while a seizure is occurring
- Interictal SPECT: a procedure done between seizures
At the child’s bedside, we inject a small amount of a medication, called an isotope, through an intravenous (IV) line into a vein. The isotope is carried to the brain through the bloodstream and lasts for six hours. It does not cause seizures. It travels to the place in the brain where there is greatest blood flow, which may be the location of the seizure.
For an ictal SPECT, we inject the isotope during a seizure. For an inter-ictal SPECT, we inject the isotope between seizures; this can be done during an outpatient visit. After the injection, the child will lie flat on a special table that will slide into the scanner.
About Subtraction Ictal SPECT Co-Registered to MRI (SISCOM)
SISCOM is an important process that helps locate the focus of seizure activity. Doctors use it to compare the ictal and inter-ictal SPECT scans with MRI images, and to create a three-dimensional brain image. This image highlights the areas of increased blood flow, thus helping determine the area of seizure focus.
Transcranial Magnetic Stimulation (TMS)
Like a functional MRI, transcranial magnetic stimulation (TMS) identifies functional areas of the brain, especially language and movement areas. Test results can help doctors plan surgery by identifying where the brain’s critical structures are located.
During the test, the child sits in a chair or on the parent’s lap. The technician places electrodes on the child’s skin, including on the arm, face and leg. The child watches a screen to see pictures or words that should trigger a response, and interacts with the neurologist. The neurologists holds a wand, and uses it to deliver a “pulse,” or several pulses, of electromagnetic energy to the scalp, targeting specific brain regions.
Each pulse only lasts a few seconds, and causes a vibration on the child's scalp. The equipment makes loud noises during the test.
Neuropsychological evaluations test abilities such as cognition, language, visual-spatial skills, memory, problem solving, motor skills and behavioral functioning.
Neuropsychological evaluations help our team:
- Understand how epilepsy may affect the child’s behavior and abilities
- Identify problems such as anxiety, depression and learning difficulties
- Recognize side effects from epilepsy medication
Neuropsychological evaluation is best done early in a child’s treatment to help establish a baseline. Then, it is often repeated at regular intervals to help our team monitor how the child is doing. Results help us make recommendations for a child’s individualized education program (IEP) or 504 plan for school.
Depending on the child’s age and ability, evaluations last two to six hours.
Genetic Testing and Counseling
About 40% of all epilepsy is thought to be due to a genetic cause. Genetic test results can help guide treatment decisions, and indicate whether a child’s siblings or future children might also be at risk for epilepsy. Genetic testing is sometimes definitive, but not always.
Our genetic counselors can:
- Review the child’s medical history and family medical history
- Talk about genetic tests that could be useful
- Schedule and coordinate genetic testing
- Explain what genetic test results mean
- Work with the multidisciplinary team to adjust treatment based on genetic test results
- Follow up with families when new genetic tests are available
Review Tests and Develop Treatment Plan
After testing and imaging are completed, our experts will discuss the results at our weekly multidisciplinary epilepsy surgery conference and develop a recommended treatment plan for your child.
You and your child will meet with one of our epileptologists (neurologists who specialize in the treatment of epilepsy) and neurosurgeons to review all test results and discuss next steps.
If your family and the epilepsy surgery team decide to move forward with the surgical recommendations, a team member will contact you to schedule your child’s surgery and admission to Cincinnati Children’s.
What Are the Types of Epilepsy Surgery?
Electrode Placement / Intracranial Monitoring
When non-invasive tests do not provide enough detailed information for the surgical team, we may recommend intracranial monitoring. This is the case for less than half of all epilepsy surgery patients.
Intracranial monitoring involves performing surgery to temporarily place electrodes directly in locations of the brain which may be causing seizures.
There are two types of surgical techniques for implanting electrodes.
A craniotomy involves removing part of the skull and placing electrodes on specific brain sites using computer and imaging guidance to allow for precise placement.
Robotic-assisted Stereo EEG
A stereo EEG involves drilling small holes through the skull and passing depth electrodes through the brain in the locations which may be causing seizures.
After the electrodes are in place, the child spends several days in the hospital’s Epilepsy Monitoring Unit. There, the electrodes help measure seizure activity, showing the team where seizures are starting and how they are spreading. The child’s anti-seizure medication may be reduced or stopped temporarily to allow seizures to take place.
The electrodes typically remain in place until they are surgically removed during a second surgery that typically takes place about a week after the first surgery. Depending on the type of surgical technique used to implant the electrodes (craniotomy or stereo EEG), surgical removal of the seizure focus may occur at that time as well.
Other surgical options may be recommended.
Resective / Ablative Surgery
Resection means removing the portion of the brain that is causing seizures (seizure focus). Ablation involves using a medical device (such as a laser) to destroy the seizure focus. Surgeries are tailored to the child; one of several types may be recommended.
The brain is divided into four different lobes, or sections: temporal, frontal, occipital and parietal. A lobectomy involves surgically removing the lobe where the seizures are starting. The surgeon uses intracranial monitoring to precisely locate the seizure focus and avoid healthy tissue.
A temporal lobectomy is the most common type of lobectomy, followed by frontal lobectomy. These surgeries can be very successful in reducing or even eliminating seizures.
Cortical Resective Surgery
Cortical resection surgery involves removing the part of the brain that is causing seizures. This surgery is similar to a lobectomy, but does not involve removing an entire lobe of the brain.
Cortical resections can be effective when imaging tests or intracranial electrodes identify a specific area of the brain that is causing seizures.
Hemispherectomy / Hemispherotomy
Our team may recommend a hemispherectomy or hemispherotomy when a child’s seizures are coming from several different locations on the right or left side of the brain. These surgeries can be especially beneficial to children who are experiencing life-threatening seizures or seizures that are causing significant brain damage.
A hemispherectomy involves removing the connection between the right and left side of the brain. This prevents seizures from spreading from the diseased part of the brain to the part that is not causing seizures. A hemispherotomy involves removing the right or left side of the brain.
Laser ablation is a less invasive alternative to traditional epilepsy surgery that can be used to destroy (rather than remove) brain tissue that is causing seizures.
During laser ablation surgery, the neurosurgeon does not need to remove part of the patient’s skull to access the brain. Instead, he or she guides a laser applicator to the target area through a small incision in the skull, while the patient is in a magnetic resonance scanner. Laser light heats and destroys the target area, with minimal risk of potential damage to surrounding, healthy tissue. The technology uses functional MRI, stereotactic navigation and intraoperative neuromonitoring, so that the surgeon can see the target lesion in real time as it is being destroyed.
Palliative (non-curative) Surgery
These surgeries are considered for patients who have epilepsy involving multiple regions of brain, or areas of the brain that likely cannot be removed without causing impairment.
Corpus callosotomy involves cutting the corpus callosum, a band of nerve fibers that connects the two halves of the brain. This interrupts the spread of seizures from one side of the brain to the other.
Corpus callosotomy may be recommended for children who experience generalized seizures, especially the type that involve “drop attacks,” when the child suddenly slumps, falls forward or drops to the ground.
After this procedure, about 75 percent of patients no longer experience “drop attacks,” although they may continue to have other types of seizures.
Vagus Nerve Stimulation
The vagus nerve is one of the largest nerve systems in the body. It helps control several systems, including the heart and digestive tract.
A vagus nerve stimulator is used to reduce the frequency of seizures, and can also help stop a seizure. The surgeon implants this small device below the child’s left clavicle (collarbone), and attaches it to the vagus nerve with a small electrode wire. The device stimulates the vagus nerve, cycling on and off around the clock. If a parent or caregiver notices that a seizure is beginning, he or she can “swipe” a special magnet over the vagus nerve stimulator to send a stronger, immediate stimulation of the nerve. This can stop the seizure from progressing.
Vagus nerve stimulators are sometimes recommended for children with partial and generalized seizures who are not experiencing adequate seizure control with medication alone. The device can help significantly reduce seizures in approximately 50 percent to 75 percent of patients.
Responsive Neuro Stimulation (RNS)
Responsive Neuro Stimulation (RNS), or NeuroPace RNS® System, has two main parts: a generator and wires placed into the brain region(s) causing seizures. The RNS generator collects data sent from the brain. You upload this data to the cloud every day. The RNS can be programmed in the office so that it sends a signal to the brain when the earliest sign of a seizure is detected. This signal is a therapy. It is designed to stop the seizure at this earliest sign, even before your child has symptoms of a seizure. RNS decreases seizure frequency and severity in most patients who have the device.
Placement of a RNS device is an option for children with seizures occurring in 1 or 2 small areas of the brain. If removing these brain regions will cause serious side effects, RNS can be a way to target these brain regions without removing the tissue.
Deep Brain Stimulation
Deep Brain Stimulation (DBS) is a treatment that involves placement of depth electrodes into a "deep" area of brain, typically in or near an egg-like structure called the thalamus. A generator is also implanted away from the head. This generator is connected to the depth electrodes and is programmed to send regular signals to the brain. DBS can be used in many different neurological disorders. DBS can be performed for children with epilepsy who have either had brain surgery and continue to have seizures, or children who are not candidates for resective brain surgery. When performing DBS for epilepsy, usually one electrode is placed in each brain half (hemisphere).
What are the Risks and Side Effects of Epilepsy Surgery?
For children undergoing epilepsy surgery, the rate of surgical complications is low. Risks include blood loss that requires a transfusion; anesthesia-related problems; stroke; and even death.
After surgery, your child may experience short-term and/or long-term side effects. Some children have minor, temporary problems including a headache, mental dullness, jaw pain, earache, puffiness, or bruising around the eye on the side where surgery was performed.
Less common are problems associated with memory, emotions and behavior. These can be short term or persist, requiring therapy. Patients who undergo a hemispherectomy will have permanent partial paralysis on one side of their body.
Our pediatric neurosurgeons have extensive experience with these types of surgeries, and plan very carefully in order to minimize risks and side effects. Our team will talk to you about the risks and side effects associated with the type of surgery your child may have.
How Well Does Epilepsy Surgery Work?
The goal of epilepsy surgery is to dramatically reduce the severity and frequency of seizures and, when possible, eliminate them altogether. At Cincinnati Children’s, more than 50% of patients who undergo surgery to remove the seizure focus achieve complete seizure freedom post-surgery. Patients who do not achieve complete seizure freedom post surgery typically experience a significant reduction in seizures, sometimes more than a 90% reduction.
Every patient is different, and every surgery is different. Our experienced neurosurgeons recommend surgery for patients they think will respond well, but they cannot predict whether your child will experience seizure freedom. Before surgery, our team will give you a sense of what to expect and how to prepare.
What to Expect After Your Child’s Surgery
How Long Will My Child Be in the Hospital?
It depends. If your child only has surgery to remove or disconnect the seizure focus, the hospital stay could be three to five days. If your child has a two-step surgery—one to place the intracranial electrodes and one to remove or disconnect the seizure focus—the hospital stay could be more like two weeks. If your child has a vagus nerve stimulator implantation surgery, the hospital stay is less than 24 hours.
Will My Child Need Rehabilitation?
Some children need rehabilitation therapy after epilepsy surgery, but many do not. Those who do include patients who have had a hemispherectomy, which causes partial paralysis on one side of the body. Physical and occupational therapy can help these children adapt so that they can do everyday tasks and live life to the fullest.
Some children may experience problems with memory, mental processing or language after surgery. Rehabilitation therapy often can help them regain abilities.
When Can My Child Return to School?
Your child can return to school after he or she is fully recovered, usually within two to six weeks after surgery. Our social worker can assist with any school re-entry issues following surgery.
When Will You Follow up With My Child?
Our epilepsy surgery team will want to see your child at two weeks and three months after surgery to evaluate how effective the surgery was and see what follow-up care might be needed. Eventually, your child will return to our clinic once a year for about five years. Your child will undergo neuropsychological testing at one, two and five years to evaluate progress and identify any concerns.
Follow up for vagus nerve stimulator transplantation is different; those patients return to the clinic at two weeks after surgery, and then weekly for three weeks to make adjustments to the device as needed.
For out-of-town families, we will coordinate long-term follow-up care with your primary physician or neurologist in your hometown as needed.