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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.”

newborn in incubator

Tracking oxygen saturation with vital signs to identify vulnerable preemies

 

Khodayar-Rais-Bahrami

What’s known

Critically ill infants in neonatal intensive care units (NICU) require constant monitoring of their vital signs. Invasive methods, such as using umbilical arterial catheters to check blood pressure, are the gold standard but pose significant health risks. Low-risk noninvasive monitoring, such as continuous cardiorespiratory monitors, can measure heart rate, respiratory rate and blood oxygenation. A noninvasive technique called near-infrared spectroscopy (NIRS) can gauge how well tissues, including the brain, are oxygenated. While NIRS long has been used to monitor oxygenation in conditions in which blood flow is altered, such as bleeding in the brain, how NIRS values relate to other vital sign measures in NICU babies was unknown.

What’s new

A research team led by Khodayar Rais-Bahrami, M.D., a neonatologist at Children’s National Health System, investigated this question in 27 babies admitted to Children’s NICU. The researchers separated these subjects into two groups: Low birth weight (LBW, less than 1.5 kg or 3.3 pounds) and moderate birth weight (MBW, more than 1.5 kg). Then, they looked for correlations between information extracted from NIRS, such as tissue oxygenation (specific tissue oxygen saturation, StO2) and the balance between oxygen supply and consumption (fractional tissue oxygen extraction, FTOE), and various vital signs. They found that StO2 increased with blood pressure for LBW babies but decreased with blood pressure for MBW babies. Brain and body FTOE in LBW babies decreased with blood pressure. In babies with abnormal brain scans, brain StO2 increased with blood pressure and brain FTOE decreased with blood pressure. Together, the researchers suggest, these measures could give a more complete picture of critically ill babies’ health.

Questions for future research

Q: Can NIRS data be used as a surrogate for other forms of monitoring?

Q: How could NIRS data help health care professionals intervene to improve the health of critically ill infants in the NICU?

Source: Significant correlation between regional tissue oxygen saturation and vital signs of critically ill infants.” B. Massa-Buck, V. Amendola, R. McCloskey and K. Rais-Bahrami. Published by Frontiers in Pediatrics Dec. 21, 2017.

Children’s National Fetal Medicine Institute hosts 2nd annual International Symposium on the Fetal Brain


The Children’s National Health System Fetal Medicine Institute hosted the 2nd annual International Symposium on the Fetal Brain in August 2017 in Washington, D.C.

Speakers at this year’s symposium focused on the following four areas:

  • Brain Development in an Unsupportive In Utero Environment – Diagnosis and Consequences
  • Supporting Brain Development in the Ex Utero Fetus: How Far Are We From Optimal?
  • Genomic and Epigenomic Mechanisms Underlying Differences in Brain Development
  • The Emergence of Consciousness and Pain Sensation

Adré J. du Plessis, M.B.Ch.B., M.P.H., Director of the Fetal Medicine Institute and Division Chief of Fetal and Transitional Medicine hosted the conference. In his opening remarks Dr. du Plessis noted “Our goal has been to gather together a diverse group from across the spectrum of disciplines focused on the well-being of the fetal brain and to engage all disciplines together.”

Diana-Bianchi-at-ISFB

Diana Bianchi, MD gives her keynote presentation on non-invasive fetal testing at the second annual International Symposium on the Fetal Brain.

Invited, internationally renowned speakers presented on diverse topics, including Diana Bianchi, Director of the Eunice Kennedy Shriver National Institute of Child Health and Human Development who spoke on the “Non-Invasive Fetal Testing Beyond Karyotype: What’s in it for the Fetal Brain?”

A new component to the symposium was the clinically-focused breakfast breakout sessions, created based on feedback from attendees of the 2016 Symposium. Sessions covered varied topics such as “Fetal Ultrasound: the Cornerstone of Fetal Neurodiagnosis,” “The Essentials of Neurogenetic Testing,” “Developing a Transitional Fetal-Neonatal Program” and “Using MRI to Advance Fetal Neurodiagnosis.”

The conference started with an exciting discussion by Alistair Gunn, M.B.Ch.B., Head of the Department of Physiology at the University of Auckland. His presentation “Fetal Heart Rate: What It Does and Does Not Tell Us” explored the considerable body of evidence that essentially all decelerations are mediated by chemoreflex responses to repeated hypoxia and that the parasympathetic autonomic nervous system is the critical regulator of both fetal heart rate and heart rate variation in labor.

Following a voting process from the symposium’s external speakers, the inaugural Andrea Poretti Abstract Award was presented to Katherine Ottolini for her poster titled: Breastmilk Feeds Improve Brain Microstructural Development in Very Premature Infants.

For more information about the sessions and speakers at the 2017 Symposium, please visit our website.