Tag Archive for: hemimegalencephaly

The endovascular embolic hemispherectomy team.

New hemimegalencephaly procedure is all about teamwork

Children’s National experts pioneered a novel approach of inducing strokes to stop seizures and improve neurodevelopmental outcomes in newborns under three months old with hemimegalencephaly (HME). The procedure, called an endovascular embolic hemispherectomy, can be safely used to provide definitive treatment of HME-related epilepsy in neonates and young infants. Monica Pearl, M.D., neurointerventional radiologist, and Panagiotis Kratimenos, M.D., Ph.D., neonatologist, discuss why having a multidisciplinary team skilled at this procedure is the reason we’re the only center in the world capable of providing this treatment.

baby with brain monitor

The history behind the novel hemimegalencephaly procedure

Traditionally, when a baby is diagnosed with hemimegalencephaly (HME), doctors turn to a hemispherectomy at 3 months of age, which involves surgically removing half of a baby’s brain. At Children’s National Hospital, our doctors pioneered the endovascular embolic hemispherectomy, an approach using induced controlled strokes to eliminate the affected part of the brain, halting seizures. Monica Pearl, M.D., neurointerventional radiologist, and Tammy Tsuchida, M.D., Ph.D., neonatal neurologist, talk about this life-changing procedure.

Angelique and family pose in front of their house

Inducing strokes to better treat babies with hemimegalencephaly

When a family from Texas received a shocking diagnosis for their newborn daughter, they knew there was one place they needed to go – Children’s National Hospital in Washington, D.C. At birth, Angelique was diagnosed with a rare and devastating condition known as hemimegalencephaly (HME) which causes uncontrollable and frequent seizures. Monica Pearl, M.D., neurointerventional radiologist, and the team at Children’s National have pioneered an approach to treat HME, where they induce controlled strokes to eliminate the affected part of the brain, halting seizures in their tracks. They’re the only team in the world doing this work. Angelique’s parents knew the clock was ticking — every day they waited meant irreversible damage to their daughter’s developing brain.

illustration of a brain

Inducing strokes in newborns to treat hemimegalencephaly

“The number one thing people are perplexed by is how well these babies recover and how they can only live with half a brain,” said Tayyba Anwar, M.D., neonatal neurologist and co-director of the Hemimegalencephaly Program at Children’s National Hospital. “People think if a child has half a brain that’s damaged or dysplastic, how are they functioning? But babies are so resilient. It still amazes me.”

The big picture

Children’s National experts have pioneered a novel approach of inducing strokes to stop seizures and improve neurodevelopmental outcomes in newborns under three months old with hemimegalencephaly (HME).

The procedure, called an endovascular embolic hemispherectomy, can be safely used to provide definitive treatment of HME-related epilepsy in neonates and young infants, according to a study in the Journal of NeuroInterventional Surgery.

Prior to this approach, the standard treatment was an anatomic hemispherectomy — surgical removal of the affected half of the brain. But infants had to be at least three months old to undergo such a complex surgery. Delaying surgery meant the persistent seizures compromised the development of the healthy half of the brain.

What they’re saying

In this video, Dr. Anwar and Panagiotis Kratimenos, M.D., Ph.D., neonatologist and co-director of Research in Neonatology at Children’s National, discuss the critically important neonatal care provided to babies who undergo endovascular embolic hemispherectomy and how protocols have evolved with each case to make this less invasive approach a feasible early alternative to surgical hemispherectomy.

Drs. Anwar and Kratimenos are part of the multidisciplinary team of neonatal neurologists, neurointerventional radiologists, neonatologists and neurosurgeons performing endovascular hemispherectomies.

Illustration of brain and brainwaves

Effective treatment for children with hemimegalencephaly

Illustration of brain and brainwaves

Anatomic or functional hemispherectomy are established neurosurgical treatment options and are recommended for effective seizure control and improved neurodevelopmental outcome in patients with HME.

Endovascular hemispherectomy can be safely used to provide definitive treatment of hemimegalencephaly (HME) related epilepsy in neonates and young infants when intraprocedural events are managed effectively, a new study finds.

The authors of the study, which published in the Journal of NeuroInterventional Surgery, add that this less invasive novel approach should be considered a feasible early alternative to surgical hemispherectomy.

Why it matters

Anatomic or functional hemispherectomy are established neurosurgical treatment options and are recommended for effective seizure control and improved neurodevelopmental outcome in patients with HME. Hemispherectomy in the neonate, however, is associated with high surgical risks and most neurosurgeons defer surgical hemispherectomy until the patient is at least 8 weeks old. This delay comes at a significant neurocognitive cost as the uncontrolled seizures during this time of deferred surgery have a deleterious effect on future neurocognitive outcome.

Why we’re excited

“The procedure we have developed, endovascular hemispherectomy by transarterial embolization, acutely stops seizures and this cessation of seizures has been sustained in each of the treated patients,” says Monica Pearl, M.D., director of the Neurointerventional Radiology Program at Children’s National Hospital and the study’s lead author.

This treatment option – performed early in life – provides hope and a better quality of life for these patients post procedure.

What’s been the hold-up in the field?

Currently, the only effective treatment option is hemispherectomy. With the patient population of neonates and young infants, hemispherectomy has a very high mortality and complication rate resulting in most neurosurgeons deferring treatment until at least 8 weeks. This leaves neonates and young infants without effective treatment options and on multiple antiseizure medications in an effort to control the seizures

How does this work move the field forward?

“Embolization provides a highly effective treatment option that acutely stops seizures during a time period of critical neurodevelopment and one in which traditional open neurosurgical procedures are not viable options,” Dr. Pearl says. “Specifically, we can consider and perform embolization in children as young as one or two weeks of age rather than waiting until at least 8 weeks of age. The impact of earlier intervention – acutely stopping the seizures, reducing the dose and number of antiseizure medications and avoiding more invasive surgical procedures (hemispherectomy, shunt placement) – appears to be dramatic in our recent series. We are conducting long term studies to assess this effect on neurodevelopmental outcome.”

How is Children’s National leading in this space?

Dr. Pearl and the late Taeung Chang, M.D., neurologist at Children’s National, pioneered this concept and treatment pathway. The multidisciplinary team is led by Dr. Pearl, who has performed all the embolization procedures (transarterial embolization/endovascular hemispherectomy) and Tayyba Anwar, M.D., Co-Director, Hemimegalencephaly Program at Children’s National Hospital. Our epilepsy team, neonatology team and neurosurgery team work collaboratively managing the patients before and after each procedure.

model of the brain

Treating newborns with hemimegalencephaly by inducing strokes

model of the brain

Experts at Children’s National Hospital have pioneered a novel approach using controlled strokes to stop seizures and improve neurodevelopmental outcomes in newborns under three months born with hemimegalencephaly (HME). They now consider it their new standard of care for babies in this age group with HME and refractory epilepsy.

Asking a physician to induce strokes in newborns is asking her to do something contrary to her training. But over the past eight years, experts at Children’s National Hospital have pioneered a novel approach using controlled strokes to stop seizures and improve neurodevelopmental outcomes in newborns under three months born with hemimegalencephaly (HME). They now consider it their new standard of care for babies in this age group with HME and refractory epilepsy.

“We have demonstrated the ability to intervene and stop the intractable seizures during a critical time of neurodevelopment in which no other effective medical or surgical option exists. That is extremely rewarding,” said Monica Pearl, M.D., director of the Neurointerventional Radiology Program at Children’s National. Children’s National is the only center in the world currently offering this treatment. A multi-disciplinary team led by Dr. Pearl; Taeun Chang, M.D., director of the Neonatal Neurology and Neonatal Neurocritical Care Program; neurophysiologist and neonatal neurologist Tammy Tsuchida, M.D., Ph.D.; and other experts has now successfully treated seven patients using this minimally-invasive approach.

“We want patients and providers to understand this is a better alternative to a delayed hemispherectomy, the standard of care currently offered to newborns with HME,” said Dr. Chang.

The best treatment for newborns with hemimegalencephaly

HME, a rare congenital condition occurring in a handful of newborns each year, is characterized by abnormal growth and enlargement of half of the brain which leads to intractable seizures. The seizures often result in severe cognitive delays and hemiparesis. The standard treatment is an anatomic hemispherectomy — surgical removal of the affected half of the brain, allowing the remaining half of the brain to develop and function without constant seizures.

Such a large and complex surgery poses serious risks for infants younger than three months, leaving doctors with the difficult choice to delay surgery until these newborns grow bigger and stronger, even as they are experiencing seizures. These persistent seizures compromise the development of the healthy half of the brain. One study reports as much as a drop of 10 to 20 IQ points with each month’s delay in surgical hemispherectomy.

“I was willing to consider performing these procedures because there is a clear, unmet medical need and these babies are in dire circumstances,” Dr. Pearl said. “Waiting for curative hemispherectomy means more than just lost time; uncontrolled seizures and anti-seizure medications have detrimental effects on the ‘normal,’ unaffected parts of the brain. We needed a better option for these patients.” Dr. Pearl said that complete embolization of the affected hemisphere as both primary and definitive treatment had never been described. They could only find one example in the literature – a paper from 1995 – suggesting embolization as an adjunct to surgery, and nothing suggesting it as a primary modality.

About the care received

Dr. Pearl is one of only a handful of dedicated pediatric neurointerventionalists across the country with neurovascular expertise in people of all ages, in particular neonates and young infants. For these procedures to be performed safely, the neurointerventionalist must be proficient in obtaining femoral arterial access and navigating small caliber cervicocerebral blood vessels that are less than one millimeter in diameter.

Additionally, one needs a neonatal neurocritical care service and NICU that can medically manage large strokes and their potential complications in newborns. Dr. Chang has developed a specialized protocol based on decades of managing strokes and other acute brain injuries in newborns. She created the neonatal neurocritical care service at Children’s National, the only one in the region and the largest in the world.

“Our teams are fortunate in that we each respectively have extensive prior experience in treating and managing neonates and very young infants for various cerebrovascular disorders,” Dr. Pearl said. “We relied on this collective experience to make this hemispheric embolization pathway possible.”

How it happens

To perform the embolizations, Dr. Chang and her team first optimizes control of the seizures using medications. Dr. Pearl places a sheath in the femoral artery using ultrasound guidance – a delicate task in a neonate whose femoral artery diameter is only two to three millimeters. She then navigates a catheter up the aorta and selects the targeted carotid artery using radiographic guidance. What follows is a set of intricate navigations to direct the microcatheter through small blood vessels in the brain, often less than one millimeter.

Using x-ray guidance, Dr. Pearl injects contrast through the microcatheter to visualize the arterial anatomy and advance the microcatheter into position for embolization. She uses glue that hardens when exposed to blood, blocking off the blood supply to the seizure-inducing areas. The process is repeated until the blood supply to the entire affected hemisphere is occluded. Meanwhile, Dr. Chang and her team monitor the brain’s electrical activity using an electroencephalogram (EEG) to watch how the brain responds to each stroke. The surgical epilepsy, neonatal neurocritical care and neonatology teams are all in constant communication throughout the procedure.

Together, they have to contend with the same symptoms patients have immediately following a stroke, most notably brain swelling that can cause bleeding and herniation. The resultant brain swelling is complicated further by the already enlarged hemisphere of the brain. Using neuroprotective strategies learned from treating over a thousand newborns with perinatal brain injury, Dr. Chang and her team and the NICU coordinate to minimize brain swelling and protect the healthy half of the brain by tightly controlling the brain temperature, glucose, sodium levels, and blood pressure. Over the course of a few weeks, Dr. Pearl performs three to four embolization sessions to halt blood supply to the seizing half of the brain.

“The risks of intracranial vasospasm and hemorrhage during embolization are higher in this distinct group of patients compared to other neonates requiring embolization, such as in vein of Galen malformations. These events must be controlled immediately to prevent complications and I know I only have seconds to react,” Dr. Pearl said.

“Here, we have the cultivation of brain-centric neonatal care, a large level IV tertiary NICU with expertise in keeping critically ill babies alive and rare pediatric neurologic subspecialists like Dr. Pearl and myself. All of this is what makes this level of innovation possible,” Dr. Chang said. Now, they wish this minimally invasive approach to be available to all newborns with HME and refractory epilepsy.

“This is not a fluke. This is not a one-time thing. Our team at Children’s National has been perfecting this method for close to a decade,” Dr. Chang said. As for proof, her answer is clear.

Bella when she was sick

Preserving brain function by purposely inducing strokes

Bella when she was sick

Born to young parents, no prenatal testing had suggested any problems with Bella’s brain. But just a few hours after birth, Bella suffered her first seizure – one of many that would follow in the ensuing days. After brain imaging, her doctors in Iowa diagnosed her with hemimegalencephaly.

Strokes are neurologically devastating events, cutting off life-sustaining oxygen to regions of the brain. If these brain tissues are deprived of oxygen long enough, they die, leading to critical loss of function – and sometimes loss of life.

“As physicians, we’re taught to prevent or treat stroke. We’re never taught to inflict it,” says Taeun Chang, M.D., director of the Neonatal Neurology and Neonatal Neurocritical Care Program at Children’s National Hospital.

That’s why a treatment developed at Children’s National for a rare brain condition called hemimegalencephaly is so surprising, Dr. Chang explains. By inflicting controlled, targeted strokes, Children’s National physician-researchers have treated five newborns born with intractable seizures due to hemimegalencephaly before they’re eligible for epilepsy surgery, the standard of care. In the four surviving infants, the procedures drastically reduced or completely relieved the infants of hemimegalencephaly’s characteristic, uncontrollable seizures.

The most recent patient to receive this life-changing procedure is Bella, a 13-month-old from Iowa whose treatment at Children’s National began within her second week of life. Born to young parents, no prenatal testing had suggested any problems with Bella’s brain. But just a few hours after birth, Bella suffered her first seizure – one of many that would follow in the ensuing days. After brain imaging, her doctors in Iowa diagnosed her with hemimegalencephaly.

A congenital condition occurring in just a handful of children born worldwide each year, hemimegalencephaly is marked by one brain hemisphere growing strikingly larger and dysplastic than the other, Dr. Chang explains. This abnormal half of the brain is highly vascularized, rippled with blood vessels needed to support the seizing brain. The most conspicuous symptoms of hemimegalencephaly are the numerous seizures that it causes, sometimes several in the course of an hour, which also may prevent the normal half of the brain from developing and learning.

Prior studies suggest early surgery achieves better developmental outcomes with one study reporting as much as a drop of 10-20 IQ points with every month delay in epilepsy surgery.

The standard treatment for unilateral megalencephaly is a dramatic procedure called a hemispherectomy, in which surgeons remove and disconnect the affected half of the brain, allowing the remaining half to take over its neurological duties. However, Dr. Chang says, implementing this procedure in infants younger than 3 months of age is highly dangerous.  Excessive, potentially fatal blood loss is likely in infants younger than 3 months who have a highly vascularized brain in the setting of an immature coagulation system. That leaves their doctors with no choice but to wait until these infants are at least 3 months old, when they are more likely to survive the surgery.

However, five years ago, Dr. Chang and her colleagues came up with a different idea when a newborn continued to have several seizures per hour despite multiple IV seizure medications: Because strokes cause irreversible tissue death, it might be possible to effectively incapacitate the enlarged hemisphere from within by inflicting a stroke on purpose. At the very least, this “functional embolization” might buy time for a traditional hemispherectomy, and slow or halt ongoing brain damage until the infants are able to withstand surgery. Ideally, this procedure may be all some children need, knocking out the offending hemisphere completely so they’d never need a hemispherectomy, which has late complications, such as hydrocephalus.

A pediatrician friend of Bella’s paternal grandparents read a story on Children’s National website about Darcy, another baby who’d received functional embolization a year earlier and was doing well. She contacted Dr. Chang to see if the procedure would be appropriate for Bella.

Within days, Bella and her family headed to Washington, D.C., to prepare for functional embolization herself. Within the first weeks of life, Bella underwent three separate procedures, each three to four hours long. Under real-time fluoroscopic and angiographic guidance, interventional neuroradiologist Monica Pearl, M.D., threaded a micro-catheter up from the baby’s femoral artery through the complex network of blood vessels all the way to her brain. There, in targeted branches of her cerebral arteries, Dr. Pearl strategically placed liquid embolic agent to obstruct blood flow to the abnormal half of Bella’s brain.

Immediately after the first procedure, the team had to contend with the same consequences that come after any stroke: brain swelling that can cause bleeding and herniation, complicated further by the already enlarged hemisphere of Bella’s brain. Using neuroprotective strategies learned from treating hundreds of brain-injured newborns, the neonatal neurocritical care team and the neonatal intensive care unit (NICU) minimized the brain swelling and protected the normal half of the brain by tightly controlling the brain temperature, her sugar and electrolyte levels, her blood pressure and coagulation system.

As the brain tissue in the oversized hemisphere died, so did the seizures that had plagued Bella since birth. She has not had a seizure since she left Children’s National more than one year ago. Her adoptive parents report that Bella is hitting many of the typical developmental milestones for her age: She’s getting ready to walk, blowing kisses and saying a few words. Physical, speech and occupational therapy will keep her moving in the right direction, Dr. Chang says.

“We believe that Children’s National is the only place in the world that’s treating newborns in this way to preserve their futures,” Dr. Chang says. “We’re privileged to be able to care for Bella and other kids with this rare condition.”

Bella’s transfer and successful procedures required the support and collective efforts of many within the hospital organization including William D. Gaillard, M.D., and his surgical epilepsy team; interventional neuroradiology with Dr. Monica Pearl; Neurosurgery; Neonatology and the NICU; social work; and even approval from Robin Steinhorn, M.D., senior vice president of the Center for Hospital-Based Specialties, and David Wessel, M.D., executive vice president and Chief Medical Officer.

“While obvious credit goes to the medical team who saved Bella’s future and the neonatal intensive care nurses who provided exceptional, intensive, one-on-one care, Bella’s team of supporters extend to all levels within our hospital,” Dr. Chang adds.

Also read:

Bella's brain scan

Born with hemimegalencephaly, Bella now has a bright future

bella's brain scans

PDF Version

Bella was born with a rare condition (hemimegalencephaly) in which one half of the brain developed abnormally, causing seizures. The textbook approach is to let babies grow big enough for a dramatic surgery. But Bella’s left hemisphere was triggering so many seizures each hour that waiting would mean her life would be defined by severe disability. Children’s National Hospital is believed to be the only center in the world that calms these seizures through controlled strokes.

Procedure one occurred five days after Bella came to Children’s National Hospital from Iowa, when she was 13 days old. The team first optimized control of her seizures and obtained special magnetic resonance images to plan their approach. They glued up the branches of the left posterior cerebral artery and branches of the left middle cerebral artery. Bella had a tiny bleed that was controlled immediately in the angio suite and afterwards in the Children’s National neonatal intensive care unit.

Procedure two occurred 10 days later when Bella was 23 days old. The team waited until brain swelling had subsided and brain tissue loss had occurred from the first procedure. This time, they glued up the remaining branches of the left posterior cerebral artery and some branches of the left anterior cerebral artery.

The third and final procedure was done nine days later when Bella was 29 days old.  This time the team glued and coiled, placing little wire coils where it was unsafe to use glue, getting at the remaining small and numerous branches that remained of the left anterior cerebral artery.

Also read:
two doctors perform surgery

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.

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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.