Hear a Patient Power interview with Dr. Joseph Sullivan, director of the UCSF Pediatric Epilepsy Center, on the latest treatments to control seizures.
Hello. This is Andrew Schorr and welcome to Patient Power sponsored by UCSF Medical Center. We're talking about epilepsy, which is not particularly common in children, and there are differences in children and adults. We're going to explore that in the next few minutes with the director of the UCSF Pediatric Epilepsy Center at the UCSF Benioff Children's Hospital, and that's neurologist Dr. Joseph Sullivan.
Dr. Sullivan, thank you for joining us. Tell us more about how epilepsy in children is different from adults.
Epilepsy in children we like to think of as occurring in a developing brain as young as a child who is one-day old all the way up until 18 years old, and so obviously with a developing brain the impact that seizures may have on the developing brain are very different than that of an adult brain that's already been formed.
The UCSF Pediatric Epilepsy Center doesn't need to treat every child in the Bay Area, or far and wide, that has epilepsy. Many can be treated with medications, close to home, wherever that may be. Who are the kids who really would benefit from a referral to your center?
Yes absolutely. One thing you mentioned in your opening remarks was that epilepsy is not as common in children. Actually, it's not that it's not as common. It actually does affect anywhere between 1/2 and 1 percent of the population, so it's anywhere between 1 in 100 and 1 in 200 children.
The overwhelming majority of those children will respond to a seizure medication and ultimately be able to come off their seizure medication and not have additional seizures when that child has sort of outgrown their tendency to have seizures.
Unfortunately, despite the advances in new medications, there remain 20 to 25 percent of children that do not respond to multiple medication trials, and we feel that those are the children that should be seen at a comprehensive pediatric epilepsy center like UCSF. We could maybe help in further fine-tuning their diagnosis and ultimately see if there are other therapies that are available.
You're designated as a high level center, right?
Now what does that mean? So when somebody is referred to your center, how do you start to look at what are you dealing with and why that child has not responded well to medications?
The first thing that we start with, like anything else in medicine, is a thorough history and physical examination. That is no less important in pediatric epilepsy. We rely heavily on what the parents can tell us in terms of when the seizures first began and what the seizures look like. We then use outpatient EEGs to help us figure out where the seizures may be coming from together with the clinical history that we have gathered from the parent.
Sometimes that still is not enough, and we're forced to admit the child to the hospital for a video EEG study where the goal is for the child to have one of their seizures while the EEG is recording and while we can look at the video to see when the first manifestations of the seizure is apparent, and that's really the sort of first tier of studies.
Then depending on what those studies show, we can then determine if the child needs any type of neuroimaging most commonly in the form of a brain MRI to help better stratify the underlying cause of the child's seizures.
Now you have some advanced diagnostics at UCSF that they don't have everywhere. I know there is some very specialized equipment, and I know you have team members who have very specialized knowledge as well.
Yes absolutely. The whole notion of a comprehensive pediatric epilepsy center is that there are multiple subspecialists that are involved, and as neuroimaging technology is improving we're realizing that imaging is really crucial to understanding why a child may have intractable seizures.
We are very lucky here to have very experienced pediatric neuroradiologists that are skilled at looking for some of the subtle abnormalities that may be present on a child's brain MRI, and in addition we have the most up-to-date MRI scanners that are able to get much higher resolution images than even the scanners were able to five years ago.
When a child has a seizure, if you're watching it with MRI or these other techniques, can you actually see it, see the activity in the brain?
Most of the time you can. The EEG we have to remember is about 20 electrodes that are placed on the surface of the scalp, and so there are a lot of areas of the brain that because the brain is sort of folded and has different areas where the abnormal electrical activity may not actually make it out to the scalp. Those cases can be even more tricky, and that's where it's very important to actually have the video to see the seizure as well because we know from decades of experience what certain types of seizures look like if they're coming from certain areas of the brain.
That's where the neuroimaging really comes in and is very helpful because if the EEG doesn't show us what we would like, then we rely heavily on the seizure type together with any subtle MRI abnormalities to help us truly localize where the seizures may be coming from.
So if a child is not responding to medication, what other approaches do you start to think about, and how can you get information from that imaging, let's say if surgery comes into play, so you know exactly where you need to go and what you need to do?
Once we have a child who is not responding to medications, then we start to consider surgery, and we record some of their seizures and have good high-quality imaging. We then try to determine if that area where the seizures are coming from could be safely removed. This is where we use some other technologies to try and assess where language function and motor function, so the brain's ability to speak and understand spoken speech as well as move our arms and hands and legs. We certainly would not want to remove that area of brain even if the seizures were coming from there.
So once we have the MRI abnormality and have a good sense of where things are coming from, if we feel that that area is close to important areas of brain, not to say that all areas of the brain are not important, we then proceed with a test, either a functional MRI which uses the same MRI scanner but uses some special sequences with that scanner to see if we can pinpoint where eloquent functions such as language are coming from. So that's the next step.
If those areas are remote from where the area the seizure is coming from then we proceed and have a discussion together with the neurosurgeons as to what type of surgical approach would be best suited for each individual child.
And you have pediatric neurosurgeons on your team at the center?
Correct, we have two pediatric neurosurgeons.
After your discussion with other members of your team, you're presenting options to a family and maybe to a child who is cognizant of what's going on. The idea of removing some part of a child's brain is daunting, if you will, to those of us who are not in your field. We understand that a child's brain can be pretty adaptive because it's still developing. Tell us how you can successfully do that and a child can hopefully have seizures reduced or not occur anymore and go on to a normal life.
The whole notion of pediatric epilepsy, epilepsy that's occurring in the developing brain, the concern with ongoing seizures is that potentially the seizures could interrupt the normal developmental processes. At the same time, we can exploit that by using the immature brain and its ability to still undergo development and that if we intervene early some functions can actually move to other areas of the brain. It's very controversial as to whether there is a true critical time period as to when this happens. We always like to think the younger the better, and so that's one important aspect, especially in young children if they really are not responding to medications, that they really should be referred to an epilepsy center like ours.
So for example, there are some rare conditions where the entire side of the brain is either involved in an inflammatory or infectious-type process or the entire side of the brain is actually malformed and the most definitive treatment for those types of conditions is actually to remove the entire half of the brain. If you were to do that in you or I, that would lead to some devastating consequences. It still results in some problems for children, but they amazingly, after a procedure like that, months down the road will eventually walk. If it's done on the side of the brain where their language is not involved, they still talk. In fact if you do the operation early in the first couple of years of life, even on the left side of the brain where most people have their language function, , it's expected that the right side of the brain can adapt and develop language functions that would not occur if done at a later age.
Dr. Sullivan so let's just understand some of the surgical procedures there. I know the most common is something I think you call a focal resection. So you're trying to find the area where the trouble is, if you will, and take that out. Then there are some other approaches like what is a disconnection procedure?
A disconnection procedure is used in a specific type of seizure where children are having falls. So there are many different types of seizures and that's true of both pediatric and adult epilepsy, but there's one very disabling seizure type where kids can just be walking down the street and all of a sudden they drop to the ground. It happens so quickly that they can't even put their arms out to protect themselves. These are the unfortunate children that you see that may wear helmets to prevent head injuries.
The thought with these seizures is that they are occurring in one area of the brain but spreading so quickly to the other side of the brain that the entire brain gets involved and they fall to the ground. The purpose of the disconnection procedure is not necessarily to stop the seizure. We're still leaving the area of brain that may be generating the seizure, but we're trying to disconnect the left side of the brain from the right side of the brain so that that seizure cannot spread. Therefore the child doesn't fall and doesn't result in many of the catastrophic injuries that these children experience.
What is vagus nerve stimulation and where does that come in?
Vagus nerve stimulation is sort of the final option that we consider in children who have seizures that are not responding to medications and despite an exhaustive evaluation including high-quality neuroimaging. We just either can't figure out where the seizure is coming from or the seizure is coming from multiple places, or the seizure is coming from an area of brain that is not able to be removed. These are the kids that unfortunately are not candidates for open brain surgery, and then we'd consider the vagal nerve stimulator.
The vagal nerve stimulator is a small little pacemaker-type device that's actually implanted underneath the skin in the left side of the chest wall, and then there's a small wire that's wrapped along the vagus nerve, which is a big nerve that travels on both sides of the neck, we have two vagus nerves, we usually use the left side; and it travels from the brain and innervates a lot of things including our heart, our stomach, our intestines, but it also receives a lot of signals and so sends a lot of projections so-to-speak to both sides of the brain. The theory is that through repetitive electrical stimulation of the vagus nerve that this can some way alter the brain chemistry that it will improve seizures.
It is definitely effective. Unfortunately it is not as effective as we would like it to be. I often tell families that a reasonable expectation and result from the vagal nerve stimulator would be a 50 percent reduction of seizures in 50 percent of children. So it's a little bit of a lot of numbers there, and a few percent of children actually will become seizure-free, but in my experience that actually is a minority.
The advantage of the procedure is that it is low risk. It's an outpatient surgical procedure that still involves general anesthesia, but generally the kids go home the same day, and the parents can actually interact with the stimulator with a little magnet. They can actually turn the stimulator on and give their child an extra dose of stimulation so-to-speak, and I've found this to be effective for some children who have prolonged seizures or when they tend to have a cluster of seizures occur one after the other. So when the parents see this they can use this little magnet, place it over the child's chest, and this tells the stimulator to give an additional dose of electricity.
Dr. Sullivan, just a couple of more questions. One is when someone comes to UCSF for pediatric epilepsy treatment, when a child comes, there's a whole team that comes into play. So we talked about neurosurgeons, you're a neurologist, and I know there are others on your team. There are even I imagine child life specialists and rehab specialists too?
Absolutely. So even those these children often have very frequent seizures, to bring them into the hospital we typically would like to record at least three to five of their typical seizures to make sure that they truly all are the same both in how they appear and how they look on the EEG, and that can often mean a one-week hospital stay and sometimes longer. So you can imagine a child sitting in a hospital room for one week basically just waiting to have a seizure that they can get pretty bored, so we rely very heavily on our child life specialists not only to distract the child while they're having the EEG electrodes put into place but also to keep them entertained while they're in the hospital.
As for the rehab specialists, they are an extremely important part of our center in the sense that even though we go in and when we do surgery and remove a part of the brain that we don't think is crucial for the child's development there are often some temporary or transient deficits after surgery such as weakness, inability to walk, problems with being able to use fine motor movements of their hands, and so we really rely heavily upon our rehab service to get these kids back up and walking and doing their activities of daily living as soon as possible.
Last question for you. You see who comes in, and you see who goes out, and you see children I'm sure for followups. Are you encouraged with progress you're making in that for many of these children with the right treatment even if they came in and were not responding to medications initially and were seen as a more difficult situation that you can help many of them get back to a pretty full life?
I'm encouraged. I think there is still a lot of work to be done but I really think that the advances that have been occurring really in neuroimaging are really allowing us to identify very subtle abnormalities that previously would have gone undetected and made the surgical evaluation of many of these children very challenging. So I think that while surgery can be a very attractive option for many children, there are a handful of children that despite surgery or despite the newest medications still continue to have seizures. I think it's with ongoing basic science research and genetics and understanding some of the genetic underpinnings of epilepsy and improving the different types of drugs we have available to us will ultimately result in improvement in our ability to care for these children.
Dr. Joseph Sullivan, we wish you well with that quest for yet more refined care for all children with epilepsy, and we want to thank you for what you do as director of the UCSF Pediatric Epilepsy Center. Thanks for joining us.
Thank you for having me.
For more information about the UCSF Pediatric Epilepsy Center or any of the physicians and services of UCSF, please call the Physician Referral Service. The number is (888) 689-UCSF (689-8273). You've been listening to Patient Power brought to you by UCSF Medical Center. I'm Andrew Schorr. Remember, knowledge can be the best medicine of all.
Recorded February 2009
Reviewed by health care specialists at UCSF Benioff Children's Hospital.
This information is for educational purposes only and is not intended to replace the advice of your doctor or health care provider. We encourage you to discuss with your doctor any questions or concerns you may have.
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