Many patients with uncontrolled seizures are unaware that they can be helped – and providers have an opportunity to start them toward a better quality of life simply by explaining the latest options. In this concise talk, Edward Chang, MD, chair of the UCSF Department of Neurosurgery, describes both traditional and minimally invasive procedures (including laser ablation and various types of neurostimulation) and offers the data on outcomes.
My name is Eddie chang. I'm a professor and chair of the department of neurosurgery at UCSF, One of my main specialties is epilepsy surgery for people who are suffering from epilepsy. We usually start thinking about surgery if they're having a lot of uncontrolled seizures and have tried multiple medications, usually about 2 to 3 is sufficient to know if the medications are to control the seizures. In the last 10 years, we've seen a huge change in our approach to epilepsy surgery. Traditionally the main approach was through a craniotomy where we remove a piece of the skull and then remove the part of the brain that's causing the seizures, which still is very effective and very important for our care of patients with uncontrolled seizures. But we have a lot more options now than we had just 10 years ago. There are basically two big categories as we think about epilepsy surgery. One is where you remove or oblate the part of the brain that's causing the seizures. The other is a form of what we call neuromodulation, where use electrical stimulation to try to reduce or stop the seizures for a plate of procedures. The use of lasers has been one of the most important tools that has come online. What's really nice about the laser approach is that it only requires making a 1.5 or two millimeter hole in the skull to place a laser probe that involves a robot that allows us to aim the laser to the spot as accurately as possible. The laser primarily works to a blade, the brain tissue by increasing the temperature at the tip of the laser probe and when that temperature goes up, it can cause a very focal kind of injury to where the seizure focuses at the same time, we can monitor what the spread of that temperature is, so that it doesn't spread to the other parts of the brain that we don't want to be treated by burning that one focal spot where the seizures are coming from. Many cases, it can stop the seizures altogether. The best candidates for laser surgery are those in whom the seizure focus is really coming from a single well defined spot, almost anywhere in the brain. We estimate that about 50% of people who have this surgery will have some meaningful improvement of their seizures for patients that have the laser surgery and doesn't work. They can still be candidates for traditional open surgery or using some of the neuromodulation devices as well. UCSF, we've done over 100 laser therapies and we were one of the first groups in California to adopt this new form of treatment. The development of a device called the responsive neuro stimulation system is one of the more exciting therapies that we've had for epilepsy in the last 10 years. It's a device that allows you to essentially record and stimulate from the parts of the brain that are causing seizures. I think about it, like it's a pacemaker for the brain that allows us to detect when a seizure is about to begin and then delivers an electrical impulse to try to stop the seizure. One of the big advantages of the RNS system is that it can be programmed, it can be turned off, it can be turned on. The stimulation parameters can be very, very tightly and precisely personalized to an individual seizure patterns and I think that this is going to improve over time and that's been a huge advantage of this technology over some of the traditional approaches to epilepsy surgery or one of the highest volume centers for RNS Surgery. I've done about 100 over the last five years, 70% of patients will have a meaningful benefit from the treatment and recent studies have shown that this improvement actually Changes over time. Initially patients maybe more around 30, but over multiple years it can actually increase its efficacy. Another really important form of neuromodulation through electrical stimulation in the brain is called deep brain stimulation or DBS. DBS is another form of targeting parts of the brain where seizures generate or parts of the brain that are involved in the seizure networks such as the thalamus. Unlike the R. N. S, the DBS is not something that is triggered on demand. It's a therapy that's essentially constantly being applied. People who we typically consider for DVs have tried other forms of surgery. Some people may also be candidates if the main focus of their seizures is not really clear or multifocal, which means they would not be candidates for traditional surgery or RNS therapy. The efficacy of DBS is similar to RNS. Initially, patients will get about 30 to 40% efficacy, but over the years can be up to 60 or 70% effective. We have a large experience with DBS surgery. Our center was also involved in the original study that validated the efficacy of DBS for refractory epilepsy, Vagal nerve stimulation, or VNS is another important treatment for refractory epilepsy. It's actually been around for at least 2 to 3 decades. The VNS surgery involves placement of a wire in the neck at the level of the vagal nerve. And the surgery involves wrapping a series of small coils from that wire around the vagal nerve and that wires tunneled underneath the skin too. A battery which lays in upper part of the chest. The mechanism of VNS is actually not clearly understood, but the stimulation on the nerve actually can travel up through the vagus nerve and affect different parts of the brain in a more general way than some of the other focused forms of neuromodulation. VNS therapy is a good option for people who may not want to have surgery in the brain. About a third of patients will have at least 50% reduction in the amount of seizures that they have in summary. There are a lot of new therapies for people who are suffering from uncontrolled seizures. One of the key questions is really thinking about which is the right one for you, All of these therapies that we've discussed today have pros and cons and their success completely depends on understanding the seizure and the epilepsy in the individual. We generally first think of applying the traditional or laser surgery because these therapies have the chance of completely stopping the seizures altogether when that's not possible. For example, if the seizures come from a part of the brain, that's not safe to do surgery or remove or if the seizures come from multiple parts of the brain. Those traditional approaches or laser surgery may not be as effective. The neuromodulation options have been fantastic to help us help those patients as well. In most cases, we're looking for a meaningful reduction of at least 50% of the seizure burden with the neuromodulation approaches for all of these approaches. It's really important to remember that most patients will still continue to take their medications after the therapy. It's only after a couple of months or years if someone is seizure free that we would consider removing the main medications for seizures. Epilepsy surgery has been around for a long time and the data over many years has shown that it can be very safe and effective for controlling seizures. However, there's not a lot of awareness, how effective it can be and there are many patients out there who could benefit from it. One of our hopes is by the development of these new approaches, especially these new, minimally invasive approaches. More patients will consider this as an important part of their therapy and treatment to help get the seizures under control.
