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Chima Oluigbo examines a patient

Eradicating epilepsy with Visualase

Chima Oluigbo examines a patient

Chima Oluigbo, M.D., and his team are using Visualase to identify and eliminate seizure foci and provide patients with a minimally invasive procedure for treating epilepsy.

About one in 26 people will be diagnosed with epilepsy in their lifetime. That adds up to about 3.4 million people in the U.S., or about 1 percent of the population nationwide. This condition can have huge consequences on quality of life, affecting whether children will learn well in school, eventually drive a car, hold down a job or even survive into adulthood.

For most of those that develop epilepsy, medications can keep seizures in check. However, for about a third of patients, this strategy doesn’t work, says Chima Oluigbo, M.D., an attending neurosurgeon at Children’s National Health System. That’s when he and his team offer a surgical fix.

Epilepsy surgery has come a long way, Dr. Oluigbo explains. When he first began practicing in the early 2000s, most surgeries were open, he says – they involved making a long incision in the scalp that can span half a foot or more. After drilling out a window of skull that can be as long as five inches, surgeons had to dig through healthy brain to find the abnormal tissue and remove it.

Each part of this “maximally invasive” procedure can be traumatic on a patient, Dr. Oluigbo says. That leads to significant pain after the procedure, extended hospital stays of at least a week followed by a long recovery. There are also significant risks for neurological complications including stroke, weakness, paralysis, speech problems and more.

However, open surgery isn’t the only option for epilepsy surgery anymore. Several new minimally invasive alternatives are now available to patients and the most promising, Dr. Oluigbo says, is called Visualase. He and his team are the only surgeons in the region who perform this procedure.

In Visualase surgeries, Dr. Oluigbo and his colleagues start by making a tiny incision, about 5 millimeters, on the scalp. Through this opening, they bore an even tinier hole into the skull and thread a needle inside that’s about 1.6 millimeters wide. “The brain barely notices that it’s there,” he says.

The tip of this wire holds a laser. Once this tip is placed directly at the seizure foci – the cluster of nerve cells responsible for generating a seizure – the patient is placed in an intraoperative magnetic resonance imaging (MRI) device. There, after checking the tip’s precise placement, the surgeons turn the laser on. Heat from the laser eradicates the foci, which the surgeons can see in real time using MRI thermography technology. The margins of the destroyed tissue are well-defined, largely sparing healthy tissue.

After the wire is removed, the incision is closed with a single stitch, and patients go home the next day. The majority of patients are seizure free, with rates as high as 90 percent for some types of epilepsy, Dr. Oluigbo says. Although seizure-free rates are also high for open procedures, he adds, Visualase spares them many of open surgeries’ painful and difficult consequences.

“Having done both open surgeries and Visualase,” Dr. Oluigbo says, “I can tell you the difference is night and day.”

Although open procedures will still be necessary for some patients with particularly large foci that are close to the surface, Dr. Oluigbo says that Visualase is ideal for treating medication-resistant cases in which the foci are buried deep within the brain. A typical example is a condition called hypothalamic hamartoma, in which tumors on the hypothalamus lead to gelastic seizures, an unusual seizure type characterized by uncontrollable laughing. He also uses Visualase for another condition called tuberous sclerosis, in which waxy growths called tubers develop in the brain, and for cancerous and benign brain tumors.

It’s gratifying to be able to help these children become seizure-free for the rest of their lives, says Dr. Oluigbo – even more so with the numerous updates he receives from families telling him how much this procedure has improved their children’s lifestyle.

“Visualase has completely changed the way that we approach these patients,” Dr. Oluigbo says. “It’s extraordinary to see the effects that this one procedure can have on the quality of life for patients here at Children’s National.”

NeuroPace RNS x-ray

New brain “pacemaker” offers new hope for refractory epilepsy

NeuroPace RNS x-ray

Example of NeuroPace RNS System placement.

If a child’s refractory seizures – seizures that don’t respond to medication – are originating in a part of the brain that is central to function (for example, impacting memory or verbal skills) the standard next step – surgical resection – is not an option for seizure reduction or relief. In most cases, these children are followed, more medications are tried, and other strategies attempted, but few viable options exist to ease their symptoms.

It’s possible that the next generation of implantable neurostimulators, which act as a type of pacemaker for the brain, might make a difference for some children previously left with no answers. Children’s National neurosurgeon Chima Oluigbo, M.D., in collaboration with the Comprehensive Pediatric Epilepsy Program at Children’s National, is looking at how these devices might be used to reduce or eliminate refractory seizures in pediatric patients. One example of this type of device is the RNS System.

“The RNS has been FDA approved for adults since 2013,” says Dr. Oluigbo, who recently implanted a NeuroPace RNS in the first pediatric patient at Children’s National, and one of the first young patients in the country. “The safety and efficacy data in the adult population, now gathered from a cohort of more than 800 adults, is showing positive outcomes so far. That allows pediatric neurosurgeons to consider an off-label use of this device for patients under the approved usage age of 18, when no other treatments exist.”

The RNS operates differently from previous neuro pacemaker-style devices. It is a “closed-loop” system that doesn’t require external activation once a seizure has started. Instead, the precise location of seizure origination is identified via functional magnetic resonance imaging (fMRI). Leads are then placed at the seizure site via surgery, and once activated, the RNS monitors and self-activates when pre-seizure electrical impulses are detected. The device responds by emitting a series of its own electrical impulses to interrupt and reset the brain’s seizure activity. The RNS system’s ability to continuously monitor the patient also allows physicians to get an inside look at the ongoing brain function of these young patients.

“Children’s National is one of the first places to apply the use of this device in children, because we are one of the few locations on the East coast with the multi-disciplinary expertise to implement it safely and effectively,” says Dr. Oluigbo. “Our clinical epilepsy team has been imaging and treating children with epilepsy for almost 30 years. With one of the oldest neurosurgical programs in country and our technological capabilities, Children’s National becomes the perfect location to explore how technology like this can improve the quality of life for our patients, many of whom have previously been told there is nothing more we can do to help.”

De-personalized data from patients who receive the NeuroPace RNS will be shared with the company in the hopes that the data will assist the FDA in assessing the appropriateness of extending the age range of approval from 18 and above to 12 and above.

“Our hope is to contribute to the body of data about this device and determine if it will improve the lives of our younger patients the way it has already been done for adults,” Dr. Oluigbo concludes. “Kids’ brains may respond differently, however, sharing our patients’ experiences and outcomes will help us identify whether or not this is a viable and promising option for more children with refractory epilepsy.”

Oluigbo and Myseros neurosurgery

Working miracles to control seizures and preserve brain power in newborns

Oluigbo and Myseros neurosurgery

In the spring of 2017, a multidisciplinary team applied an innovative approach to help preserve function in the working right hemisphere of a baby who experienced her first seizure hours after birth.

When orderly early fetal brain development is disturbed in one half of the brain, infants can be born with hemimegalencephaly—a rare occurrence—that results in one of the brain’s two hemispheres being oversized, heavy and malformed. This brain malformation arises early in the fetal period of life, is not inherited and is associated with seizures early in life.

Children with hemimegalencephaly can develop horrible seizures within the first hours or days of life. According to published research, every month these infants experience uncontrolled seizures correlates to a steep decline in IQ.

Because these types of seizures do not respond to multiple anti-seizure medications—medicines which may also cause worrisome side effects of their own in neonates—care teams attempt to schedule surgery as soon as feasible to remove or disconnect the hemisphere triggering the damaging seizures. “The ‘bad’ brain does not sustain any function and it interferes with the ‘good’ brain doing what it needs to do,” says William D. Gaillard, M.D., chief of Children’s division of Epilepsy and Neurophysiology and chief of Neurology.

Hemispherectomy is intricate surgery on an organ that is softer than normal and crisscrossed with a tangle of blood vessels that supply the damaged hemisphere with blood. Because of the risks of life-threatening blood loss in very young infants, the dramatic surgery is usually not performed until babies are at least 3 months old and weigh at least 10 pounds.

The challenge: The vulnerable babies who most need relief, infants who have been seizing since early life, are too young for the operation.

Neurosurgeons have clamped the carotid artery that supplies blood to the brain to minimize blood loss when the hemisphere is surgically removed. Dr. Gaillard says knowledge of that approach led the team to think: What if we use embolization—blocking blood supply to targeted locations in the brain—to achieve the same effect?  The plan effectively destroys the malformed brain from within, neutralizing its ability to cause the seizures.

“It was eye-opening for us to think about actually inflicting brain injury as a way of treating something in the brain that was causing seizures. That is really novel in itself: We’re thinking out of the box in applying existing techniques in a different age group. The conventional thinking with newborns is to let them be; their seizures don’t look that bad,” says Taeun Chang, M.D., director of Children’s Neonatal Neurology and Neonatal Neurocritical Care Program.

“We have evidence to suggest this is a safe and effective way of avoiding recurrent seizures and minimizing the need to give these infants potentially toxic medications so early in life. Ultimately, this helps a select group of babies who need the surgery to get to the point of being old enough to have it—all the while, sparing the healthy part of their brain,” Dr. Gaillard adds.

Darcy hemimegalencephaly

Once the embolization ended Darcy’s most severe seizures, the little girl could make eye contact, started smiling, and then graduated from smiling to full laughs. In weekly physical therapy, the infant works on tummy time, head control and ensuring her eyes track.

In the spring of 2017, the multidisciplinary team applied the innovative approach to help preserve function in the working right hemisphere of a baby named Darcy Murphy. Darcy experienced her first seizure hours after she was born, and when she arrived at Children’s National had been in and out of two different emergency rooms in another state for the first few weeks of her life.

The team explained to the Murphy family that Darcy was on multiple medications, but her seizures continued unabated. The options included inducing a coma, sending Darcy home despite ongoing seizures or minimally invasive embolization.

“We would not have even posed this if we were not confident in our ability to do the procedure and deal with potential complications,” Dr. Chang says.

“Oh my gosh, as a parent you know what you’re doing is permanent,” says Rachel Murphy, 29, Darcy’s mom said of the decisions that she and husband Ryan, 33, faced for the youngest of their three children. “What if it’s not the right decision? What if in a week they come out with a new procedure you could have done? We were horrified all the time. The nice part with this procedure is the reward is apparent very quickly, and it just gets better. You don’t have to wait two years to know you made the right decision. You can see half a brain is better than the whole thing for this specific child.”

Once the embolization ended Darcy’s most severe seizures, the little girl could initiate and maintain eye contact with family members, started smiling and then graduated from smiling to full laughs. In weekly physical therapy, the infant works on tummy time, head control and ensuring her eyes track.

Children’s multidisciplinary care team includes experts in newborn intensive care (neonatologists) to aggressively manage seizures in the traditional fashion as they occur and to monitor vital signs; a neonatal neurologist/neurointensivist at the bedside and in the Angio suite monitoring Darcy’s brain activity; a neonatal epileptologist; a surgical epilepsy team; an interventional neuroradiologist; neurosurgeons to perform the delicate functional hemispherectomy to remove any residual brain tissue from the bad hemisphere; and physical therapists working to help Darcy achieve maximum function after surgery.

“We were just like one unit in the sense of being able to provide coherent, comprehensive care. It’s about blood pressure management, breathing, electrolytes, making sure everything is right for going to the operating room,” Dr. Chang explains. “Darcy’s case highlights the ways in which Children’s National is different and offers personalized care that is superior to other centers.”

The team, which recently published a case report of two previous serial embolizations followed by hemispherectomy, plans follow-up papers describing EEG manifestations during an acute stroke in a newborn, advice to the field on best practices for the embolization and using cooling to control the planned brain injury during embolization hemispherectomy.

Revised Nov. 7, 2017

Related resources

Chima Oluigbo

A novel way to treat intractable epilepsy caused by hemimegalencephaly

Chima Oluigbo

A multidisciplinary team led by Chima Oluigbo, M.D., F.R.C.S.C., pioneered a novel technique to preserve newborns’ healthy brain tissue, buying time until the infants became old enough to undergo a hemispherectomy.

What’s known

Hemimegalencephaly is an extremely rare birth defect in which one side of the brain grows larger than the other. This anomaly typically leads to severe, recurrent seizures that can be difficult to control solely with medications. While the seizures themselves are detrimental to the developing brain, the amount of medications used to reduce seizure frequency often come with significant side effects and have the potential to hamper brain growth. Hemispherectomy, a radical surgery in which one half of the brain is removed, is often the most successful way to treat severe and intractable epilepsy. However, this surgery can be challenging to perform successfully in very young babies.

What’s new

In this case report, the Children’s National Health System Epilepsy Team led by Chima Oluigbo, M.D., F.R.C.S.C., a pediatric neurosurgeon; Tammy N. Tsuchida, M.D., PhD., a pediatric surgical epileptologist; Monica Pearl, M.D., a pediatric interventional neuroradiologist; Taeun Chang, M.D., a neonatal neurointensivist; and the neonatal intensive care team explored the possibility of using minimally invasive surgery to cut off the blood supply to the brain hemisphere responsible for generating seizures in newborns with hemimegalencephaly. This procedure, they reasoned, could buy time for babies to mature and become more resilient to withstand the future hemispherectomy while also lessening the damage caused by uncontrolled, recurrent seizures. The case report focused on the first two patients with hemimegalencephaly who had sequential procedures to gradually restrict blood flow to the affected brain hemisphere within their first few weeks of life, followed by hemispherectomies at a few months of age. This novel approach significantly lessened their seizures until hemispherectomy, allowing these children to continue to grow and develop seizure-free.

Questions for future research

Q: Which patients are best suited for this surgical procedure?
Q: How can surgeons reduce the risk of excessive blood loss during hemispherectomy caused by the growth of additional blood vessels after flow through the brain’s major vessels has been blocked?
Q: What are the long-term outcomes for infants who undergo these procedures?

Source: “ ‘Endovascular embolic hemispherectomy’: A strategy for the initial management of catastrophic holohemispheric epilepsy in the neonate.” Oluigbo, C., M.S. Pearl, T.N. Tsuchida, T. Chang, C.-Y. Ho and W. D. Gaillard. Published by Child’s Nervous System October 29, 2016.
Chima Oluigbo

The benefits of deep brain stimulation for pediatric patients

Chima Oluigbo

There was no effective treatment for uncontrolled, difficult, and sometime painful movements associated with movement disorders. That is, before the development of deep brain stimulation (DBS) techniques.

Children’s National Health System is one of only two children’s hospitals with fully integrated DBS programs. Chima Oluigbo, M.D., who leads the pioneering Deep Brain Stimulation Program within Children’s Division of Neurosurgery, is one of few pediatric deep brain stimulation experts in North America and cross-trained in pediatric and functional neurosurgery.

Dr. Oluigbo says the effects of DBS are often dramatic: 90 percent of children with primary dystonia show up to 90 percent symptom improvement.

A 6-year-old boy with dystonia so severe that his body curved like a “C” was one of the first patients to undergo the procedure at Children’s National. Six weeks later, he gained the ability to sit straight and to control his hands and legs. He also was able to smile, an improvement that brought particular joy to his parents.

Inside the brain with movement disorders

Patients with movement disorders experience difficulties due to neurological dysfunction that impact the speed, fluency, quality, and ease in which they move. In these cases, neurons in the brain’s motor circuits misfire. Through the use of DBS, neurosurgeons can synchronize neuronal firing and accomplish the previously impossible: restoring muscle control to patients with these disorders.

Movement disorders are common in children. “It’s not just numbers, it’s also about impact. Think about the potential of a child who is very intelligent and can contribute to society. When that child is not able to contribute because he or she is disabled by a movement disorder, the lost potential is very significant. It has an impact,” Dr. Oluigbo says.

What is deep brain stimulation?

DBS uses an implantable device to send continuous, low-level electrical impulses to areas deep within the brain. The impulses prevent the brain from firing abnormal signals that are linked to movement disorders and seizures. When a child is considered to be a candidate for the technique, here’s what happens next:

  1. Imaging: Magnetic resonance imaging (MRI) helps pinpoint the area of brain tissue responsible for movement disorders and informs the treatment plans.
  2. Neurotransmitter implant procedure: Using minimally invasive neurosurgery techniques, doctors access the brain through a tiny incision in the child’s skull and place thin, insulated wires (leads) in the area of brain tissue responsible for the condition.
  3. Pulse generator implant procedure: The pulse generator (neurostimulator) is a battery-operated device that sends low-level electrical impulses to the leads. During a separate procedure, the pulse generator is implanted near the child’s collarbone. Leads are threaded under the child’s skin to connect with the pulse generator.
  4. Stimulation treatments: Once the leads and pulse generator are connected, the child receives a continuous stream of electrical impulses. Impulses are generated by the neurostimulator, travel through the leads, and end up in the deep tissue of the brain. Here, they block abnormal signals that are linked to the child’s movement disorder.
  5. Follow-up care: The child will likely need deep brain stimulation throughout his or her lifetime to make sure the device is working correctly and to adjust the neurotransmitter settings to meet his or her changing needs.

Deep brain stimulation at Children’s National

Children’s National is currently conducting clinical trials seeking to expand the use of this procedure to patients with cerebral palsy, one of the most common dystonias. The effective use of deep brain stimulation requires ongoing attention from a multidisciplinary team (from neuropsychology to rehabilitation medicine), giving seamless care under one roof.

There is evidence to suggest that this technique could be used to aid people with memory disorders, patients in minimally conscious states, and patients with incurable epilepsies.