Catherine Limperopoulos

Tracking preemies’ blood flow to monitor brain maturation

Catherine Limperopoulos

A new study led by Catherine Limperopoulos, Ph.D., finds that blood flow to key regions of very premature infants’ brains is altered, providing an early warning sign of disturbed brain maturation well before such injury is visible on conventional imaging.

Blood is the conduit through which our cells receive much of what they need to grow and thrive. The nutrients and oxygen that cells require are transported by this liquid messenger. Getting adequate blood flow is especially important during the rapid growth of gestation and early childhood – particularly for the brain, the weight of which roughly triples during the last 13 weeks of a typical pregnancy. Any disruption to blood flow during this time could dramatically affect the development of this critical organ.

Now, a new study by Children’s National Health System researchers finds that blood flow to key regions of very premature infants’ brains is altered, providing an early warning sign of disturbed brain maturation well before such injury is visible on conventional imaging. The prospective, observational study was published online Dec. 4, 2017 by The Journal of Pediatrics.

“During the third trimester of pregnancy, the fetal brain undergoes an unprecedented growth spurt. To power that growth, cerebral blood flow increases and delivers the extra oxygen and nutrients needed to nurture normal brain development,” says Catherine Limperopoulos, Ph.D., director of the Developing Brain Research Laboratory at Children’s National and senior author of the study. “In full-term pregnancies, these critical brain structures mature inside the protective womb where the fetus can hear the mother and her heartbeat, which stimulates additional brain maturation. For infants born preterm, however, this essential maturation process happens in settings often stripped of such stimuli.”

The challenge: How to capture what goes right or wrong in the developing brains of these very fragile newborns? The researchers relied on arterial spin labeling (ASL) magnetic resonance (MR) imaging, a noninvasive technique that labels the water portion of blood to map how blood flows through infants’ brains in order to describe which regions do or do not receive adequate blood supply. The imaging work can be done without a contrast agent since water from arterial blood itself illuminates the path traveled by cerebral blood.

“In our study, very preterm infants had greater absolute cortical cerebral blood flow compared with full-term infants. Within regions, however, the insula (a region critical to experiencing emotion), anterior cingulate cortex (a region involved in cognitive processes) and auditory cortex (a region involved in processing sound) for preterm infants received a significantly decreased volume of blood, compared with full-term infants. For preterm infants, parenchymal brain injury and the need for cardiac vasopressor support both were correlated with decreased regional CBF,” Limperopoulos adds.

The team studied 98 preterm infants who were born June 2012 to December 2015, were younger than 32 gestational weeks at birth and who weighed less than 1,500 grams. They matched those preemies by gestational age with 104 infants who had been carried to term. The brain MRIs were performed as the infants slept.

Blood flows where it is needed most with areas of the brain that are used more heavily commandeering more oxygen and nutrients. Thus, during brain development, CBF is a good indicator of functional brain maturation since brain areas that are the most metabolically active need more blood.

“The ongoing maturation of the newborn’s brain can be seen in the distribution pattern of cerebral blood flow, with the greatest volume of blood traveling to the brainstem and deep grey matter,” says Marine Bouyssi-Kobar, M.S., the study’s lead author. “Because of the sharp resolution provided by ASL-MR images, our study finds that in addition to the brainstem and deep grey matter, the insula and the areas of the brain responsible for sensory and motor functions are also among the most oxygenated regions. This underscores the critical importance of these brain regions in early brain development. In preterm infants, the insula may be particularly vulnerable to the added stresses of life outside the womb.”

Of note, compromised regional brain structures in adults are implicated in multiple neurodevelopmental disorders. “Altered development of the insula and anterior cingulate cortex in newborns may represent early warning signs of preterm infants at greater risk for long-term neurodevelopmental impairments,” Limperopoulos says.

Research reported in this post was supported by the Canadian Institutes of Health Research, MOP-81116; the SickKids Foundation, XG 06-069; and the National Institutes of Health under award number R01 HL116585-01.

newborn in incubator

Working to reduce brain injury in newborns

newborn in incubator

A new study from Children’s National Health System and Drexel University College of Medicine has identified a promising treatment to reduce or prevent brain injury in newborns who have suffered hypoxia-ischemia.

Research-clinicians at Children’s National Health System and Drexel University College of Medicine led the first study to identify a promising treatment to reduce or prevent brain injury in newborns who have suffered hypoxia-ischemia, a serious complication in which restricted blood flow deprives the brain of oxygen.

Consequences of brain injury resulting from oxygen deprivation affect the entire lifespan and range from mild (learning disabilities) to severe (inability to breathe, walk, talk or see). This complication can occur during or before birth due to maternal/placental problems, such as placental abruption or cord prolapse, or due to fetal/newborn issues, such as asphyxia due to labor difficulties, infection, fetal-maternal bleeding or twin-to-twin transfusion.

Published in Neonatology on Oct. 13, 2017, the study evaluated newborn experimental models exposed to hypoxia-ischemia. The experimental models were given standard cooling therapy (therapeutic hypothermia) alone and in combination with a selective Src kinase inhibitor, PP2, that blocks a regulatory enzyme of apoptosis (cell death), which intensifies as a result of hypoxia-ischemia. The Food and Drug Administration has approved a Src kinase inhibitor as an oncology treatment. This study is the first to test the benefits of blocking this enzyme in reducing the neurological damage caused by brain hypoxia-ischemia.

“In hypoxia-ischemia, CaM kinase is over-activated, but hypothermia has been shown to decrease this enzyme’s activation. We theorized that a Src kinase inhibitor, in addition to hypothermia, would further attenuate the activation of CaM kinase IV and that the result might be less brain damage,” explains Panagiotis Kratimenos, M.D., Ph.D., the study’s lead author, and a specialist in neonatology and neonatal neurocritical care at Children’s National. “From this study, we were pleased that this seems to be the case.”

The research team assessed neuropathology, adenosine triphosphate and phosphocreatine  concentrations as well as CaM kinase IV activity. The CaM kinase IV activity in cerebral tissue was 2,002 (plus or minus 729) with normal oxygen levels and in normal temperatures, 4,104 (plus or minus 542) in hypoxia with hypothermia treatment, and 2,165 (plus or minus 415) in hypoxia with hypothermia treatment combined with PP2 administration.

The authors conclude that hypothermia alone attenuated the over-activation of CaM kinase IV and improved neuropathology after hypoxia. However, the combination of hypothermia with Src kinase inhibition following hypoxia further attenuated the increased activation of CaM kinase IV, compared with hypothermia alone in the newborn experimental model brain.

Currently, the only treatment for hypoxia-ischemia is therapeutic hypothermia. Starting in the first six hours of life, doctors in the neonatal intensive care unit lower a baby’s temperature by about 3 degrees Celsius for three days. This therapy is proven to reduce neural defects by up to 30 percent, yet many infants still have poor outcomes even after the therapeutic cooling treatment.

“In oxygen deprivation of the brain, the pathways leading to cell death are over-activated, including the nuclear enzyme CaM kinase IV. We sought to intervene in this pathway to reduce the heightened cell death, which leads to brain damage,” explains Dr. Kratimenos, an assistant professor of pediatrics at The George Washington University School of Medicine and Health Sciences whose research focus is neonatal encephalopathy and therapeutic hypothermia.

To continue preclinical research into this approach, Dr. Kratimenos envisions studying the effect of other types of small molecule inhibitors to target the apoptotic cascade, perhaps in multiple doses, eliminating the potential side effects, and determining the best dose and duration of treatment.

“If confirmed by further studies, this approach─in combination with cooling─may help to further attenuate neurological damage that babies suffer after experiencing hypoxia-ischemia,” says Dr. Kratimenos.

The study co-authors include Ioannis Koutroulis, M.D., Ph.D., a faculty member in Children’s Division of Emergency Medicine; and Amit Jain, M.D.; Shadi Malaeb, M.D.; and the world-renowned neonatologist and pioneer in bioenergetics of the brain, Maria Delivoria-Papadopoulos, M.D., all of the Drexel University College of Medicine.

Adolescent brain scan from obesity study

Imaging captures obesity’s impact on the adolescent brain

Adolescent brain scan from obesity study

For the first time, a team of researchers led by Chandan Vaidya, Ph.D., chair of the Department of Psychology at Georgetown University, has used functional magnetic resonance imaging (fMRI) to capture the brain function of a small population of adolescents with obesity, both before and after bariatric surgery.

Obesity affects the whole body, from more obvious physical impacts on bones and joints to more subtle, internal impacts on organs like the brain.

For the first time, a team of researchers has used functional magnetic resonance imaging (fMRI) to capture the brain function of a small population of adolescents with obesity, both before and after bariatric surgery. The goal is to better understand the neural changes that occur when an adolescent is obese, and determine the effectiveness of interventions, such as vertical sleeve gastrectomy, at improving brain function as weight is lost.

The study, published as the November Editors’ Choice in the journal Obesity, found that executive and reward-related brain functions of study participants with obesity improved following the surgical procedure and initial weight loss.

How bariatric surgery changes the teenage brain from Research Square on Vimeo.

“We’ve known for some time that severe obesity has negative consequences on some neurocognitive function areas for adults,” says Chandan Vaidya, Ph.D., chair of the Department of Psychology at Georgetown University and a senior author of the study. “But for the first time, we’ve captured fMRI evidence in young patients, and also shown that surgical intervention and the resulting weight loss can reverse some of those deficits.”

“For me, this early evidence makes a strong case that when kids are struggling with severe obesity, we need to consider surgical intervention as an option sooner in the process,” notes Evan Nadler, M.D., director of the Bariatric Surgery Program at Children’s National Health System, who also contributed to the study. “The question that remains is whether the neurocognitive function improves more if surgery, and thus weight loss, happens earlier – and is there a time factor that should help us determine when to perform a procedure that will maximize improvements?”

The preliminary study included 36 participants and was conducted using patients recruited from the Children’s National Bariatric Surgery program, one of the first children’s hospitals to achieve national accreditation by the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program.

“We asked these questions because we know that in the kids we see, their behavioral, brain, and physical health are all very closely related to one another and have an impact on each other,” adds Eleanor Mackey, Ph.D., study senior author and co-principal investigator on the National Institute of Diabetes and Digestive and Kidney Diseases grant that funded the project. “We expected that as physical health improves, we might see corresponding improvements in brain and behavior such as cognitive and school performance.”

The study also pointed out some technical and practical challenges to studying this particular young population. Anyone with a BMI greater than 50 was not able to fit within the MR bore used in the study, preventing fMRI participation by those patients.

“In addition to future studies with a larger sample size, we’d like to see if there are neuroimaging markers of plasticity differences in a population with BMI greater than 50,” says Dr. Vaidya. “Does the severity of the obesity change how quickly the brain can adapt following surgery and weight loss?”

The abstract was selected by the journal’s editors as one that provides insights into preventing and treating obesity. It was featured at the Obesity Journal Symposium during Obesity Week 2017 in Washington, D.C., as part of the Obesity Week recognition, and a digital video abstract was also released about the findings.

An-Massaro

Continuous EEG monitoring better predicts HIE outcomes

An-Massaro

“What we were trying to determine with this study is whether evaluating the pattern of evolution of the aEEG as a whole provides more information compared with looking at snapshots in time,” explains the study’s senior author An N. Massaro, M.D.

For newborns who experience a serious complication that deprives their brain of oxygen, continuously monitoring brain activity and examining how the electrical signals evolve may be a more reliable way to identify infants most at risk for brain injury, compared with doing evaluations at discreet intervals, according to a prospective cohort study led by Children’s National Health System research-clinicians.

Amplitude-integrated electroencephalogram (aEEG) is a bedside tool that permits clinicians to monitor the complex electrical activity of the child’s brain over time. It’s a positive sign when an aEEG shows babies beginning to sleep and wake normally by the time they are 3 days old. Conversely, severely abnormal aEEG readings in the first days of life predict poor outcomes.

The Children’s team used aEEG with infants born with hypoxic-ischemic encephalopathy (HIE), one of the most severe complications that can affect full-term infants. During pregnancy, birth or shortly after birth, a hypoxic-ischemic event can occur that impedes blood flow and oxygen delivery to the brain, resulting in destruction of brain tissue. Cooling (therapeutic hypothermia) is now standard for newborns with HIE in order to stave off life-long consequences, but deaths and neurodevelopmental disability still can occur.

“We know whole-body cooling – or lowering the body’s temperature by about 3 degrees Celsius – can help vulnerable newborns survive and can protect their brains from suffering profound injuries,” says An N. Massaro, M.D., a Children’s National neonatologist and senior author of the study published online Sept. 28, 2017 in American Journal of Perinatology.  “What we were trying to determine with this study is whether evaluating the pattern of evolution of the aEEG as a whole provides more information compared with looking at snapshots in time.”

Eighty infants undergoing therapeutic cooling who met the inclusion criteria were enrolled in the five-year study, one of the largest such studies to date. The babies weighed more than 1,800 grams and were older than 35 weeks’ gestational age at birth, and either needed prolonged resuscitation after birth or had low APGAR scores – a measure of how well newborns fare outside the womb. Continuous recordings of EEG data occurred from the time of admission up to 12 hours after the infants’ temperatures were raised to normal and aEEG tracings were calculated.

After the therapeutic cooling blankets were removed, the infants underwent at least one magnetic resonance imaging (MRI) scan prior to discharge. During the routine follow-up check at about 18 months of age, the HIE survivors’ cognitive and motor skills were assessed using validated instruments.

Fifty-six of the infants in the study had favorable outcomes. Twenty-four infants had adverse outcomes, including 15 with severe brain injury detected by MRI and nine infants who died. These children had lower APGAR scores at five minutes, and were more likely to have severe HIE and to have experienced more frequent seizures.

“Infants whose aEEG abnormalities do not improve were at increased risk: Infants who do not reach a discontinuous background pattern by 15.5 hours of life, achieve cycling by 45.5 hours after birth and who fail to achieve continuous normal voltage by 78 hours after birth are most at risk for adverse outcomes,” Dr. Massaro says. “In addition to defining worrisome trends, we found that overall assessment of continuous aEEG readings through the course of hypothermia treatment provide the most meaningful predictive power. This means we can speak with families at the bedside with more confidence about their child’s outcomes after the infant undergoes cooling therapy.”

Related Resources

Sarah Mulkey

Fetal MRI plus ultrasound assess Zika-related brain changes

Sarah Mulkey

Magnetic resonance imaging and ultrasound provide complementary data needed to assess ongoing changes to the brains of fetuses exposed to Zika in utero, says Sarah B. Mulkey, M.D., Ph.D.

For Zika-affected pregnancies, fetal magnetic resonance imaging (MRI) used in addition to standard ultrasound (US) imaging can better assess potential brain abnormalities in utero, according to research presented by Children’s National Health System during IDWeek 2017. In cases of abnormal brain structure, fetal MRI can reveal more extensive areas of damage to the developing brain than is seen with US.

“MRI and US provide complementary data needed to assess ongoing changes to the brains of fetuses exposed to Zika in utero,” says Sarah B. Mulkey, M.D., Ph.D., a fetal/neonatal neurologist at Children’s National Health System and lead author of the research paper. “In addition, our study found that relying on ultrasound alone would have given one mother the false assurance that her fetus’ brain was developing normally while the sharper MRI clearly pointed to brain abnormalities.”

As of Sept. 13, the Centers for Disease Control and Prevention (CDC) reported that 1,901 U.S. women were exposed to Zika at some point during their pregnancies but their infants appeared normal at birth. Another 98 U.S. women, however, gave birth to infants with Zika-related birth defects.  And eight more women had pregnancy losses with Zika-related birth defects, according to CDC registries.

The longitudinal neuroimaging study led by Children’s National enrolled 48 pregnant women exposed to the Zika virus in the first or second trimester whose infection was confirmed by reverse transcription polymerase chain reaction, which detects Zika viral fragments shortly after exposure, and/or Immunoglobulin M testing, which reveals antibodies the body produces to neutralize the virus. Forty-six of the study volunteers live in Barranquilla, Colombia, where Zika infection is endemic. Two women live in the Washington region and were exposed to Zika during travel elsewhere.

All of the women underwent at least one diagnostic imaging session while pregnant, receiving an initial MRI or US at 25.1 weeks’ gestational age. Thirty-six women underwent a second MRI/US imaging pair at roughly 31 weeks’ gestation. Children’s National radiologists read every image.

Three of 48 pregnancies, or 6 percent, were marked by abnormal fetal MRIs:

  • One fetus had heterotopias (clumps of grey matter located at the wrong place) and abnormal cortical indent (a deformation at the outer layer of the cerebrum, a brain region involved in consciousness). The US taken at the same gestational age for this fetus showed its brain was developing normally.
  • Another fetus had parietal encephalocele (an uncommon skull defect) and Chiari malformation Type II (a life-threatening structural defect at the base of the skull and the cerebellum, the part of the brain that controls balance). The US for this fetus also detected these brain abnormalities.
  • The third fetus had a thin corpus callosum (bundle of nerves that connects the brain’s left and right hemispheres), an abnormally developed brain stem, temporal cysts, subependymal heterotopias and general cerebral/cerebellar atrophy. This fetal US showed significant ventriculomegaly (fluid-filled structures in the brain that are too large) and a fetal head circumference that decreased sharply from the 32nd to 36th gestational week, a hallmark of microcephaly.

After they were born, infants underwent a follow-up MRI without sedation and US. For nine infants, these ultrasounds revealed cysts in the choroid plexus (cells that produce cerebrospinal fluid) or germinal matrix (the source for neurons and glial cells that migrate during brain development). And one infant’s US after birth showed lenticulostriate vasculopathy (brain lesions).

“Because a number of factors can trigger brain abnormalities, further studies are needed to determine whether the cystic changes to these infants’ brains are attributable to Zika exposure in the womb or whether some other insult caused these troubling results,” Dr. Mulkey says.

What Children’s has learned about congenital Zika infection

Roberta DeBiasi

Roberta DeBiasi, M.D., M.S., outlined lessons learned during a pediatric virology workshop at IDWeek2017, one of three such Zika presentations led by Children’s National research-clinicians during this year’s meeting of pediatric infectious disease specialists.

The Congenital Zika Virus Program at Children’s National Health System provides a range of advanced testing and services for exposed and infected fetuses and newborns. Data that the program has gathered in evaluating and managing Zika-affected pregnancies and births may offer instructive insights to other centers developing similar programs.

The program evaluated 36 pregnant women and their fetuses from January 2016 through May 2017. Another 14 women and their infants were referred to the Zika program for postnatal consultations during that time.

“As the days grow shorter and temperatures drop, we continue to receive referrals to our Zika program, and this is a testament to the critical need it fulfills in the greater metropolitan D.C. region,” says Roberta L. DeBiasi, M.D., M.S., chief of the Division of Pediatric Infectious Diseases and co-leader of the program. “Our multidisciplinary team now has consulted on 90 dyads (mothers and their Zika-affected fetuses/infants). The lessons we learned about when and how these women were infected and how their offspring were affected by Zika may be instructive to institutions considering launching their own programs.”

Dr. DeBiasi outlined lessons learned during a pediatric virology workshop at IDWeek2017, one of three such Zika presentations led by Children’s National research-clinicians during this year’s meeting of pediatric infectious disease specialists.

“The Zika virus continues to circulate in dozens of nations, from Angola to the U.S. Virgin Islands. Clinicians considering a strategic approach to managing pregnancies complicated by Zika may consider enlisting an array of specialists to attend to infants’ complex care needs, including experts in fetal imaging, pediatric infectious disease, physical therapists, audiologists, ophthalmologists and radiologists skilled at reading serial magnetic resonance images as well as ultrasounds,” Dr. DeBiasi says. “At Children’s we have a devoted Zika hotline to triage patient and family concerns. We provide detailed instructions for referring institutions explaining protocols before and after childbirth, and we provide continuing education for health care professionals.”

Of the 36 pregnant women possibly exposed to Zika during pregnancy seen in the program’s first year, 32 lived in the United States and traveled to countries where Zika virus was circulating. Two women had partners who traveled to Zika hot zones. And two moved to the Washington region from places where Zika is endemic. Including the postnatal cases, 89 percent of patients had been bitten by Zika-tainted mosquitoes, while 48 percent of women could have been exposed to Zika via sex with an infected partner.

Twenty percent of the women were exposed before conception; 46 percent were exposed to Zika in the first trimester of pregnancy; 26 percent were exposed in the second trimester; and 8 percent were exposed in the final trimester. In only six of 50 cases (12 percent) did the Zika-infected individual experience symptoms.

Zika infection can be confirmed by detecting viral fragments but only if the test occurs shortly after infection. Twenty-four of the 50 women (nearly 50 percent) arrived for a Zika consultation outside that 12-week testing window. Eleven women (22 percent) had confirmed Zika infection and another 28 percent tested positive for the broader family of flavivirus infections that includes Zika. Another detection method picks up antibodies that the body produces to neutralize Zika virus. For seven women (14 percent), Zika infection was ruled out by either testing method.

“Tragically, four fetuses had severe Zika-related birth defects,” Dr. DeBiasi says. “Due to the gravity of those abnormalities, two pregnancies were not carried to term. The third pregnancy was carried to term, but the infant died immediately after birth. The fourth pregnancy was carried to term, but that infant survived less than one year.”

Catherine Limperopoulous

Brain impairment in newborns with CHD prior to surgery

Catherine Limperopoulous

Children’s National researchers led by Catherine Limperopoulos, Ph.D., demonstrate for the first time that the brains of high-risk infants show signs of functional impairment before they undergo corrective cardiac surgery.

Newborns with congenital heart disease (CHD) requiring open-heart surgery face a higher risk for neurodevelopmental disabilities, yet prior studies had not examined whether functional brain connectivity is altered in these infants before surgery.

Findings from a Children’s National Health System study of this question suggest the presence of brain dysfunction early in the lives of infants with CHD that may be associated with neurodevelopmental impairments years later.

Using a novel imaging technique, Children’s National researchers demonstrated for the first time that the brains of these high-risk infants already show signs of functional impairment even before they undergo corrective open heart surgery. Looking at the newborns’ entire brain topography, the team found intact global organization – efficient and effective small world networks – yet reduced functional connectivity between key brain regions.

“A robust neural network is critical for neurons to travel to their intended destinations and for the body to carry out nerve cells’ instructions. In this study, we found the density of connections among rich club nodes was diminished, and there was reduced connectivity between critical brain hubs,” says Catherine Limperopoulos, Ph.D., director of the Developing Brain Research Laboratory at Children’s National and senior author of the study published online Sept. 28, 2017 in NeuroImage: Clinical. “CHD disrupts how oxygenated blood flows throughout the body, including to the brain. Despite disturbed hemodynamics, infants with CHD still are able to efficiently transfer neural information among neighboring areas of the brain and across distant regions.”

The research team led by Josepheen De Asis-Cruz, M.D., Ph.D., compared whole brain functional connectivity in 82 healthy, full-term newborns and 30 newborns with CHD prior to corrective heart surgery. Conventional imaging had detected no brain injuries in either group. The team used resting state functional connectivity magnetic resonance imaging (rs-fcMRI), a imaging technique that characterizes fluctuating blood oxygen level dependent signals from different regions of the brain, to map the effect of CHD on newborns’ developing brains.

The newborns with CHD had lower birth weights and lower APGAR scores (a gauge of how well brand-new babies fare outside the womb) at one and five minutes after birth. Before the scan, the infants were fed, wrapped snugly in warm blankets, securely positioned using vacuum pillows, and their ears were protected with ear plugs and ear muffs.

While the infants with CHD had intact global network topology, a close examination of specific brain regions revealed functional disturbances in a subnetwork of nodes in newborns with cardiac disease. The subcortical regions were involved in most of those affected connections. The team also found weaker functional connectivity between right and left thalamus (the region that processes and transmits sensory information) and between the right thalamus and the left supplementary motor area (the section of the cerebral cortex that helps to control movement). The regions with reduced functional connectivity depicted by rs-fcMRI match up with regional brain anomalies described in imaging studies powered by conventional MRI and diffusion tensor imaging.

“Global network organization is preserved, despite CHD, and small world brain networks in newborns show a remarkable ability to withstand brain injury early in life,” Limperopoulos adds. “These intact, efficient small world networks bode well for targeting early therapy and rehabilitative interventions to lower the newborns’ risk of developing long-term neurological deficits that can contribute to problems with executive function, motor function, learning and social behavior.”

Vittorio Gallo

How the environment helps to shape the brain

Vittorio Gallo

“The strength, duration and timing of environmental experience influences plasticity in brain circuitry, which is made up of communication cables called axons that link neurons throughout the brain and are coated by myelin, a fatty substance that helps nerve impulses speed from place to place,” says Vittorio Gallo, Ph.D., Chief Research Officer at Children’s National and senior study author.

Researchers have long known that babies of all kinds need to be exposed to rich, complex environments for optimal brain health and potential. Exposure to new sights, sounds and other sensory experiences appears to be critical for strengthening infants’ developing brains and encouraging smoothly running neural networks. Until recently, little was known about the biological mechanisms behind this phenomenon.

In a review article published online Aug. 22, 2017 in Trends in Neurosciences, Children’s National Health System researchers discuss the role of environmental stimuli on the development of myelin—the fatty insulation that surrounds the extensions that connect cells throughout the nervous system and make up a large part of the brain’s white matter. Positive influences, such as exposure to a large vocabulary and novel objects, can boost the growth of myelin. Conversely, negative influences, such as neglect and social isolation, can harm it, potentially altering the course of brain development.

“The strength, duration and timing of environmental experience influences plasticity in brain circuitry, which is made up of communication cables called axons that link neurons throughout the brain and are coated by myelin, a fatty substance that helps nerve impulses speed from place to place,” says Vittorio Gallo, Ph.D., Chief Research Officer at Children’s National and senior study author. “As it responds to environmental stimuli, the brain continually shores up myelin’s integrity. Just as important, damaged myelin can leave gaps in the neural network which can lead to cognitive, motor and behavioral deficits.”

According to Gallo and study lead author Thomas A. Forbes, a pool of oligodendrocyte progenitor cells (OPCs) specialize in making myelin and do so from childhood into adulthood. The resulting oligodendrocyte cells (OLs) form an important working partnership with axons. From approximately 23 to 37 weeks’ gestation, OLs develop in the fetal brain and they continue to be generated after birth until adolescence.

“This dynamic feedback loop between myelin plasticity and neuronal excitability is crucial,” Forbes says. “It helps to strengthen motor and cognitive function and permits children and adults to learn new skills and to record new memories.”

In utero, genetics plays an outsized role in the initial structure of white matter, which is located in the subcortical region of the brain and takes its white color from myelin, the lipid and protein sheath that electrically insulates nerve cells. Defects in the microstructural organization of white matter are associated with many neurodevelopmental disorders. Once infants are born, environmental experiences also can begin to exert a meaningful role.

“The environment can be viewed as a noninvasive therapeutic approach that can be employed to bolster white matter health, either on its own or working in tandem with pharmacologic therapies,” Gallo adds. “The question is how to design the best environment for infants and children to grow and to achieve the highest cognitive function. An enriched environment not only involves the opportunity to move and participate in physical exercise and physical therapy; it is also an environment where there is novelty, new experiences and continuously active learning. It is equally important to minimize social stressors. It’s all about the balance.”

Among the potential interventions to boost brain power, independent of socioeconomic status:

  • Exposing children to new and different objects with an opportunity for physical activity and interaction with a number of playmates. This type of setting challenges the child to continuously adapt to his or her surroundings in a social, physical and experiential manner. In experimental models, enriched environments supported brain health by increasing the volume and length of myelinated fibers, the volume of myelin sheaths and by boosting total brain volume.
  • Exposure to music helps with cognition, hearing and motor skills for those who play an instrument, tapping multiple areas of the brain to work together collaboratively. Diffusion tensor imaging (DTI) reveals that professional pianists who began playing as children have improved white matter integrity and plasticity, Gallo and Forbes
  • At its heart, active learning requires interacting with and adapting to the environment. Generating new OLs influences learning new motor skills in the very young as well as the very old. And cognitive training and stimulation shapes and preserves white matter integrity in the aging.
  • DTI studies indicate that four weeks of integrative mind-body training alters myelination and improves white matter efficiency with especially pronounced changes in the area of the brain responsible for self-regulation, impulse control and emotion.
  • Voluntary exercise in experimental models is associated with OPCs differentiating into mature OLs. Imaging studies show a positive relationship between physical fitness, white matter health and the brain networks involved in memory.

Conversely, such negative influences as premature birth, poor nutrition, disease, neglect and social isolation can degrade myelin integrity, compromising the person’s ability to carry out basic motor skills and cognitive function. Usually, the pool of OPCs expands as the fetus is about to be born. But brain injury, lack of oxygen and restricted blood supply can delay maturation of certain brain cells and can cause abnormalities in white matter that diminish the brain’s capacity to synthesize myelin. Additional white matter insults can be caused by use of anesthesia and stress, among other variables.

The environmental influence has the potential to be “the Archimedes’ Lever to appropriating WM development among a limited range of only partially efficacious treatment options,” the authors conclude.

Exchanging ideas

Exchanging ideas, best practices in China

Exchanging ideas

Physicians from the Children’s National delegation attended the Shanghai Pediatric Innovation Forum in June 2017. Pictured (left to right): Roberta DeBiasi, M.D., Michael Mintz, M.D., Robert Keating, M.D., Lawrence Jung, M.D., Peter Kim, M.D., and Sarah Birch, D.N.P., A.P.R.N.

In late June, a delegation of international pediatric experts from Children’s National Health System journeyed across the world to learn about the practice of pediatric medicine in China and to exchange ideas with colleagues there. Leaders from several of Children’s key specialties joined the delegation, including:

The group, led by Drs. Keating and Gaillard, traveled to China with Children’s Outreach Coordinator John Walsh, whose longtime connections and close familiarity with the pediatric medical community in Hangzhou and Shanghai made the collaboration possible. The team toured several of the largest children’s hospitals in country, including The Children’s Hospital of Zhejiang University School of Medicine in Hangzhou and Shanghai Children’s Medical Center, connecting with pediatric specialists there.

“Some of the most important parts of this trip were the opportunities to exchange ideas and solidify long term relationships that will allow us to work closely with our peers in China as they develop their pediatric programs. The potential is tremendous for unique collaborations between our teams and theirs for research and the development of clinical care improvements for children,” said Roger Packer, M.D., senior vice president of the Center for Neuroscience and Behavioral Health, who joined the delegation in Beijing.

A keynote lecture and more at the 3rd China International Forum on Pediatric Development

The delegation also was honored with an invitation to participate in the 3rd China International Forum on Pediatric Development. The forum is one of the largest pediatric focused meetings in the country and is led by all the major children’s hospitals in China, including those in Beijing and Shanghai. Close to 4,000 pediatricians attended the meeting, and presenters included esteemed international leaders in pediatric medicine from around the world.

Dr. Packer delivered one of the opening keynote lectures, entitled, “Translation of molecular advances into care: the challenge ahead for children’s hospitals.” His talk focused on the tremendous promise and significant challenges posed by the latest scientific advances, through the lens of a neurologist.

“Across the world, we are looking at the same challenges: How can we use scientific advances to find better outcomes? How can we financially support the new types of interventions made possible by these molecular biologics insights when they can cost millions of dollars for one patient?”

“There’s palpable excitement that these new developments will give us potential therapies we never dreamed about before, ways to reverse what we initially thought was irreversible brain damage, ways to prevent severe illnesses including brain tumors, but the issue is how to turn this promise into reality. That’s a worldwide issue, not simply a single country’s issue,” he continued.

He also flagged mental health and behavioral health as a crucial, universal challenge in need of addressing on both sides of the Pacific.

The Children’s National delegation, including Drs. DeBiasi, Song, Keating, Gaillard and Packer were also honored to share their insight in a series of specialty-specific breakout sessions at the Forum.

Overall, the long journey opened a dialogue between Children’s National and pediatric care providers in China, paving the way for future discussion about how to learn from each other and collaborate to enhance all institutions involved.

LCModel output from 32 GA baby

Understanding the long-term consequences of prematurity

LCModel output from 32 GA baby

Children’s National Health System researchers processed H1-MRS data using LCModel software to calculate absolute metabolite concentrations for N-acetyl-aspartate (NAA), choline (Cho) and creatine (Cr). Preterm infants had significantly lower cerebellar NAA (p=<0.025) and higher Cho (p=<0.001) when compared with healthy term-equivalent infants. The area of the brain within the red box is the cerebellum, the region of interest for this study.

Premature birth, a condition that affects approximately 10 percent of births in the United States, often is accompanied by health problems ranging from difficulties breathing and eating to long-term neurocognitive delays and disabilities. However, the reasons for these problems have been unclear.

In a study published online Aug. 15, 2017 in Scientific Reports, a team of Children’s National Health System clinician-researchers reports that prematurity is associated with altered metabolite profiles in the infants’ cerebellum, the part of the brain that controls coordination and balance. Pre-term infants in the study had significantly lower levels of a chemical marker of nerve cell integrity and significantly higher concentrations of a chemical marker of cellular membrane turnover.

“These data suggest that interrupting the developing fetal brain’s usual growth plan during gestation – which can occur through early birth, infection or experiencing brain damage – might trigger a compensatory mechanism. The infant’s brain tries to make up for lost time or heal injured tissue by producing a certain type of cells more quickly than it normally would,” says Catherine Limperopoulos, Ph.D., director of the Developing Brain Research Laboratory at Children’s National and senior study author. “The more sensitive imaging technique that we used also revealed nerve cell damage from brain injuries extends beyond the site of injury, a finding that contrasts with what is found through conventional magnetic resonance imaging (MRI).”

It has long been clear that prematurity – birth before 37 weeks gestation – is accompanied by a number of immediate and long-term complications, from potential problems breathing and feeding at birth to impairments in hearing and sight that can last throughout an individual’s life.

Neurocognitive developmental delays often accompany pre-term birth, many of which can have long-lasting consequences. Studies have shown that children born prematurely are more likely to struggle in school, have documented learning disabilities and experience significant delays in developing gross and fine motor skills compared with children born at full-term.

Several studies have investigated the root cause of these issues in the cerebrum, the structure that takes up the majority of the brain and is responsible for functions including learning and memory, language and communication, sensory processing and movement. However, the cerebellum – a part of the brain that plays an important role in motor control – has not received as much research attention.

In the new study, Limperopoulos and colleagues used a specialized MRI technique that allowed them to parse out differences in which molecules are present in the cerebellum of full-term infants compared with premature infants. Their findings show a variety of differences that could offer clues to explain developmental differences between these two populations – and potentially identify ways to intervene to improve outcomes.

The researchers recruited 59 premature infants, born at 32 or fewer weeks’ gestation, and 61 healthy, full-term infants. Each baby received a special type of MRI known as proton magnetic resonance spectroscopy, or H1-MRS, that measures the concentrations of particular molecules in the brain. The full-term infants had these MRIs shortly after birth; the pre-term infants had them at 39 to 41 weeks gestational age, or around the time that they would have been born had the pregnancy continued to term.

Looking specifically at the cerebellum, the researchers found that the pre-term infants overall had significantly lower concentrations of N-acetyl-aspartate (NAA), a marker of the integrity of nerve cells. They also had significantly higher concentrations of choline, a marker of cell membrane integrity and membrane turnover.

Concentrations of creatine, a marker of stores of cellular energy, were about the same overall between the two groups. However, the researchers found that brain injuries, which affected 35 of the pre-term infants but none of the full-term infants, were associated with significantly lower concentrations of NAA, choline and creatine. Having a neonatal infection, which affected 21 of the pre-term infants but none of the full-term ones, was associated with lower NAA and creatine.

The findings could offer insight into exactly what’s happening in the brain when infants are born pre-term and when these vulnerable babies develop infections or their brains become injured – conditions that convey dramatically higher risks for babies born too early, Limperopoulos says. The differences between the full-term babies and the pre-term ones reflect disturbances these cells are experiencing at a biochemical level, she explains.

Limperopoulos and colleagues note that more research will be necessary to connect these findings to what is already known about developmental problems in pre-term infants. Eventually, she says, scientists might be able to use this knowledge to develop treatments that might be able to change the course of brain development in babies born too early, getting them on track with infants born at term.

“We know that the bodies of pre-term infants demonstrate a remarkable ability to catch up with peers who were born at full-term, in terms of weight and height. Our challenge is to ensure that preemies’ brains also have an opportunity to develop as normally as possible to ensure optimal long-term outcomes,” Limperopoulos says.

ECIN Briefing

Building resilient kids through healthy adults

ECIN Briefing

Mr. Lane, Dr. Hodgkinson, Dr. Biel, and Dr. Beers provided a briefing at the Washington, D.C., City Council in July about the Early Childhood Innovation Network, which takes evidence-based national models for early childhood mental health interventions and adds components designed to address Washington, D.C.’s unique needs.

Exposures to adverse childhood experiences are the single biggest predictor of outcomes for physical health, mental health, social functioning and academic achievement in children and into adulthood. There is evidence that negative experiences – such as poverty, housing insecurity, having a parent with untreated mental illness or actively engaged in substance abuse – have biological impacts on a child’s brain size and function.

Conversely, during the critical first few years of life, safe, stable and nurturing relationships from adult caregivers build healthy brains, even in the midst of adversity. Additionally, the ability of a child’s brain to absorb experience and to change means that early intervention to reduce exposure to or impact of these negative events can be particularly effective for young children. In a briefing for the Washington, D.C., City Council, leaders from the Early Childhood Innovation Network (ECIN) shared these facts and outlined how ECIN’s local collaborative of health, education and social service providers promotes resilient families and children through interventions designed to work best for each family.

“We are taking evidence-based practices from other places, and then personalizing them to our communities in D.C.,” says Lee Beers, M.D., co-director of the ECIN and the medical director for Municipal and Regional Affairs within the Child Health Advocacy Institute at Children’s National Health System. “We spent a lot of time seeking input and advice from primary care doctors, social services providers and community leaders, to make sure that we bring programs to clinics like the Children’s Health Center at Anacostia that are useful, sustainable and measurable for the children and families who live there.”

The network’s other co-director, Matthew G. Biel, M.D., chief of the Division of Child and Adolescent Psychiatry at MedStar Georgetown University Hospital continues, “We know that the best way to help these kids is by addressing challenges across generations – we can’t reach children without first helping the adults. In addition to evaluating for risk factors, we also need to screen for protective factors – how families can best buffer these young children from the toxic effects of adverse childhood experiences. Then, in a non-confrontational setting such as a routine primary care visit, we can provide them with additional tools to enhance those protective factors.”

A working example: HealthySteps D.C.

Drs. Beers and Biel cited the implementation of the HealthySteps program, an evidence-based intervention with a national network of over 100 pediatric and family practice sites across 15 states, locally in D.C. as one example of ECIN’s approach. The program, now underway at the Children’s Health Center at Anacostia and recently launched at the Children’s Health Center at THEARC, embeds specially trained HealthySteps specialists into the primary care team to provide parents and professionals with skills and tools that nurture healthy development in young children.

Nationwide, HealthySteps has been shown to have a significant impact on children, families and practices at relatively low cost, providing services within the primary care setting such as:

  • Early identification and access to effective interventions for development delays
  • Coaching on age-appropriate parent-child interactions and child social-emotional development
  • Support for parental depression, domestic violence, substance abuse, food, housing and other social determinants
  • Creating better integration between pediatric primary care and early childhood systems

ECIN’s D.C.-based version takes this successful national model and adds additional D.C. needs-based specific activities:

  • Each family is assigned a Family Champion who identifies and addresses specific resource needs, including mental health services, parent training, or support groups and basic needs such as insurance, housing or employment
  • HealthySteps specialists offer brief interventions within the primary care setting to address pressing needs such as maternal depression, grief and loss and child behavior management
  • HealthySteps specialists deliver specialized training to providers on child behavioral and developmental health

“Even in the short time since we implemented HealthySteps, we’re seeing significant impact around care coordination and case management for the families at our Children’s Health Center at Anacostia,” says Stacy Hodgkinson, Ph.D., a licensed clinical psychologist at Children’s National who serves as a HealthySteps specialist at the Children’s Health Center at Anacostia.

HealthySteps D.C. is the first of several initiatives under development by the Early Childhood Innovation Network. The group is also working together with additional community partners such as Educare, Martha’s Table, LIFT, and MedStar Washington Hospital Center to explore, implement and evaluate the effectiveness of programs in areas such as building social-emotional skills in young children, financial literacy and mental health support for mothers-to-be.

Community connections and coordination

“So many children with needs do not get connected to services, and the Early Childhood Innovation Network addresses this challenge. Even better, there has been a genuineness from ECIN to engaging community and earning buy-in for programs from the very beginning. They’ve made community leaders and parents an integral part of the network’s program design and implementation,” adds Ambrose Lane, Jr., chair and founder of the Health Alliance Network and chairman at the D.C. Department of Health Chronic Disease Citywide Collaborative.

Little girl eating

Daily tasks harder for girls with ASD

Little girl eating

Researchers found that girls with autism struggle with day-to-day functioning and independence skills more than boys.

Researchers at the Center for Autism Spectrum Disorders at Children’s National found something surprising in their recent study of executive function and adaptive skills. Girls, who often score well on direct assessments of communication skills, struggle more than boys with crucial tasks such as making a plan, getting organized and following through, as well as basic daily tasks like getting up and getting dressed, or making small talk.

“When parents were asked to rate a child’s day-to-day functioning, it turns out that girls were struggling more with these independence skills. This was surprising because in general, girls with ASD have better social and communication skills during direct assessments. The natural assumption would be that those communication and social skills would assist them to function more effectively in the world, but we found that this isn’t always the case,” says Allison Ratto, Ph.D., a psychologist in the Center for Autism Spectrum Disorders and one of the study’s authors. “Our goal was to look at real world skills, not just the diagnostic behaviors we use clinically to diagnose ASD, to understand how people are actually doing in their day to day lives.”

Conducted by a team within the Center for Autism Spectrum Disorders, the National Institute of Mental Health and The George Washington University, the study is the largest to date examining executive function and adaptive skills in women and girls with autism spectrum disorders (ASD).

The study collected parent-reported data from several rating scales of executive function and adaptive behavior, including the Behavior Rating Inventory of Executive Function, Parent Form (BRIEF) and the Vineland Adaptive Behavior Scales-II (VABS-II). The group included 79 females and 158 males meeting clinical criteria for autism spectrum disorders, ranging in ages from 7 to 18 years old. The groups were matched for intelligence, age and level of autism and ADHD symptoms.

Little is known about autism in females

The findings are part of a growing body of research focused on how ASD may affect females differently than males. The ratio of girls to boys with autism is approximately one to three. As a result of the larger numbers of males, existing data is predominantly focused on traits and challenges in that population. This is especially true in clinical trials, where enrollment is overwhelmingly male.

“Our understanding of autism is overwhelmingly based on males, similar to the situation faced by the medical community once confronted with heart disease research being predominantly male,” notes Lauren Kenworthy, Ph.D., director of the Center for Autism Spectrum Disorders and the study’s senior author. “We know how to identify signs, symptoms and treatments for autism in males, but we know very little about unique aspects of it in females.”

The historical lack of specific discovery around how autism presents in females may contribute to misdiagnosis or delay, and prevent implementation of necessary interventions. Such delays can have a major impact on outcomes, as recent research has demonstrated the critical importance of early diagnosis and intervention in ASD.

“Our focus in caring for children with autism is equipping all of them with strategies and skills to allow them to function and succeed in day-to-day living,” Dr. Kenworthy continues. “This study highlights that some common assumptions about the severity of challenges faced by girls with ASD may be wrong, and we may need to spend more time building the adaptive and executive function skills of these females if we want to help them thrive.”

“Enhancing our understanding of how biological differences change the presentation of autism in the long term is crucial to giving every person with ASD the tools they need to succeed in life,” she concludes.

Kazue Hashimoto-Torii and Masaaki Torii

Center for Neuroscience Research investigators join CIFASD

Kazue Hashimoto-Torii and Masaaki Torii, Collaborative Initiative on Fetal Alcohol Spectrum Disorders

Masaaki Torii, Ph.D., Kazue Hashimoto-Torii, Ph.D., and their research teams are joining Collaborative Initiative on Fetal Alcohol Spectrum Disorders, a consortium supported by the National Institutes of Health.

Kazue Hashimoto-Torii, Ph.D., Masaaki Torii, Ph.D., and the research teams they lead have joined a national research consortium for Fetal Alcohol Spectrum Disorders that is supported by the National Institutes of Health (NIH).

The Collaborative Initiative on Fetal Alcohol Spectrum Disorders (CIFASD) aims to leverage multidisciplinary approaches to develop effective interventions and treatments for Fetal Alcohol Spectrum Disorders.

“Both of our labs have been fortunate in receiving multiple R series research grants from the NIH. I am deeply honored that we now join this prestigious national consortium, which opens additional opportunities to collaborate with other labs with neurobehavioral, genetics and facial dysmorphology expertise as well as other specialized disciplines,” says Hashimoto-Torii, principal investigator in the Center for Neuroscience Research at Children’s National Health System.

Fetal Alcohol Spectrum Disorders are a constellation of conditions that result from exposure to alcohol in the womb that reflect the vastly different ways fetuses respond to that in utero insult. While early intervention is crucial, one challenge that continues to bedevil the field is trying to determine which pregnancies are most at risk.

“It is crucial to develop early and precise biomarkers for predicting children’s risk for cognitive and behavioral problems,” Hashimoto-Torii says. “Our labs will work on developing a novel approach for identifying such biomarkers.”

The Children’s researchers will examine epigenetic changes at the single cell level that may provide the earliest hint of cognitive and learning difficulties – long before children show any symptoms of such problems. Hashimoto-Torii’s lab will perform single-cell droplet digital polymerase chain reaction (PCR) based biomarker analysis of blood samples from experimental models and humans. Meanwhile, the lab run by Torii – also a principal investigator in the Center for Neuroscience Research – will collect blood samples from experimental models, perform comprehensive behavioral analysis, and evaluate potential correlations between behaviors seen in the experimental models and their drop-PCR results.

“Under the auspices of CIFASD, we ultimately hope to link these biomarkers from our lab with results that our colleagues are seeing in children in order to validate their ability to accurately predict outcomes from prenatal alcohol exposure,” she says.

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

Suresh Magge

Sudden blindness leads to unusual diagnosis

Suresh Magge

Suresh N. Magge, M.D., and his colleagues at Children’s National recently published the details of an unusual case of advanced moyamoya disease in the journal Stroke.

When Children’s National Health System Neurosurgeon Suresh N. Magge, M.D., met his new patient, the 16-year-old had suddenly lost her vision in both eyes.

To discover the reason for this abrupt loss of vision, her doctors ran a battery of tests. An ophthalmologist found no problems with her eyes.  Her optic nerves, which run signals generated from the eyes to the brain, also appeared to work normally. However, a computerized tomography scan and magnetic resonance imaging showed the unmistakable signs of a stroke in her occipital lobe, the portion of the brain responsible for interpreting signals relayed from the optic nerves.

“Her brain basically wasn’t seeing what her eyes saw,” Dr. Magge explains.

Delving deeper, her Children’s National care team found the reason why their young patient had suffered a stroke by using a cerebral angiogram, an imaging test that shows the blood vessels in and around the brain. The teen had moyamoya disease, a rare condition that causes blood vessels in the brain to narrow, often leading otherwise healthy adults and children to have strokes.

According to the National Institutes of Health, moyamoya is Japanese for “puff of smoke,” so named because of the telltale signs this condition presents on an angiogram. When arteries in the brain narrow, brain tissue becomes “thirsty” for more blood, Dr. Magge explains, leading its cells to produce chemicals that prompt new blood vessels to grow. These new collateral blood vessels often grow in a thin tangle that looks like smoke on an angiogram. Generally, however, they do not supply sufficient oxygenated blood to meet the brain’s needs, leaving it starved for oxygen. Eventually, the blood supply can get so low that patients suffer transient ischemic attacks, “mini-strokes” that temporarily deprive the brain tissue of oxygen, or full-blown strokes typically characterized by weakness, speech problems, facial paralysis or other problems.

Dr. Magge’s patient had little warning before her stroke occurred. The first major symptom that led her to seek medical attention was abrupt blindness, which Dr. Magge says is a highly unusual occurrence for a moyamoya diagnosis. That’s why he and colleagues decided to publish the details of her case as a teaching report April 14, 2017 in the journal Stroke.

The Children’s National co-authors wrote that once their patient was diagnosed with a stroke due to advanced moyamoya disease, with blood vessels severely narrowed throughout her brain, the first order of business was stabilizing her symptoms and making sure she did not have further strokes. Her blood pressure was stabilized, and she was started on aspirin therapy to decrease her risk of further strokes. She took time to recover as much as possible from her original stroke.

A few weeks later, Dr. Magge and his neurosurgery colleagues performed a type of surgery to revascularize – or restore blood flow – to areas of the brain that were still healthy but at risk of having subsequent strokes. The surgical procedure, known as pial synangiosis, reconfigures the brain’s blood vessels to make sure that these vulnerable areas of the brain have a sufficient blood supply.

Years later, Dr. Magge says, his patient is doing well, except for the original blindness, a permanent consequence of the stroke to her occipital lobe before her diagnosis. She has not had new strokes since the revascularization surgery. She will need aspirin therapy and periodic neurological checkups for the rest of her life, Dr. Magge explains, to make sure that the blood supply to her brain remains stable.

Children’s experts use a team approach to treat patients with complex care needs: Neurologists, neurosurgeons, intensivists, hematologists, anesthesiologists, neuroradiologists and nurses leverage their combined expertise with moyamoya disease to treat the complexities of this condition.

“A team approach is essential to deliver the best outcomes to children with life-changing diseases,” Dr. Magge says. “We try to help kids get back to living full and healthy lives.”

zika virus

Will the Zika epidemic re-emerge in 2017?

Anthony Fauci

Anthony S. Fauci, M.D., director of the National Institute of Allergy and Infectious Diseases at the National Institutes of Health, discussed the possibility of a reemergence of Zika virus at Children’s National Research and Education Week.

Temperatures are rising, swelling the population of Aedes mosquitoes that transmit the Zika virus and prompting an anxious question: Will the Zika epidemic re-emerge in 2017?

Anthony S. Fauci, M.D., director of the National Institute of Allergy and Infectious Diseases at the National Institutes of Health (NIH), sketched out contrasting scenarios. Last year in Puerto Rico, at least 13 percent of residents were infected with Zika, “a huge percentage of the population to get infected in any one outbreak,” Dr. Fauci says. But he quickly adds: “That means that 87 percent of the population” did not get infected. When the chikungunya virus swept through the Caribbean during an earlier outbreak, it did so in multiple waves. “We are bracing for a return of Zika, but we shall see what happens.” Dr. Fauci says.

When it comes to the continental United States, however, previous dengue and chikungunya outbreaks were limited to southern Florida and Texas towns straddling the Mexican border. Domestic Zika transmission last year behaved in much the same fashion.

“Do we think we’re going to get an outbreak [of Zika] that is disseminated throughout the country? The answer is no,” Dr. Fauci adds. “We’re not going to see a major Puerto Rico-type outbreak in the continental United States.”

Dr. Fauci’s remarks were delivered April 24 to a standing-room-only auditorium as part of Research and Education Week, an annual celebration of the cutting-edge research and innovation happening every day at Children’s National. He offered a sweeping, fact-filled summary of Zika’s march across the globe: The virus was first isolated from a primate placed in a treehouse within Uganda’s Zika forest to intentionally become infected; Zika lurked under the radar for the first few decades, causing non-descript febrile illness; it bounced from country to country, causing isolated outbreaks; then, it transformed into an infectious disease of international concern when congenital Zika infection was linked to severe neural consequences for babies born in Brazil.

zika virus

Zika virus lurked under the radar for several decades, causing non-descript febrile illness; it bounced from country to country, resulting in isolated outbreaks; then, it transformed into an infectious disease of international concern.

“I refer to Brazil and Zika as the perfect storm,” Dr. Fauci told attendees. “You have a country that is a large country with a lot of people, some pockets of poverty and economic depression –  such as in the northeastern states –  without good health care there, plenty of Aedes aegypti mosquitoes and, importantly, a totally immunologically naive population. They had never seen Zika before. The right mosquitoes. The right climate. The right people. The right immunological status. And then, you have the explosion in Brazil.”

In Brazil, 139 to 175 babies were born each year with microcephaly – a condition characterized by a smaller than normal skull – from 2010 to 2014. From 2015 through 2016, that sobering statistic soared to 5,549 microcephaly cases, 2,366 of them lab-confirmed as caused by Zika.

Microcephaly “was the showstopper that changed everything,” says Dr. Fauci. “All of a sudden, [Zika] went from a relatively trivial disease to a disease that had dire consequences if a mother was infected, particularly during the first trimester.”

As Zika infections soared, ultimately affecting more than 60 countries, the virus surprised researchers and clinicians a number of times, by:

  • Being spread via sex
  • Being transmitted via blood transfusion, a finding from Brazil that prompted the Food and Drug Administration to recommend testing for all U.S. donated blood and blood products
  • Decimating developing babies’ neural stem cells and causing a constellation of congenital abnormalities, including vision problems and contractions to surviving infants’ arms and legs
  • Causing Guillain-Barré syndrome
  • Triggering transient hearing loss
  • Causing myocarditis, heart failure and arrhythmias

When it comes to the U.S. national response, Dr. Fauci says one of the most crucial variables is how quickly a vaccine becomes available to respond to the emerging outbreak. For Zika, the research community was able to sequence the virus and launch a Phase I trial in about three months, “the quickest time frame from identification to trial in the history of all vaccinology,” he adds.

Zika is a single-stranded, enveloped RNA virus that is closely related to dengue, West Nile, Japanese encephalitis and Yellow fever viruses, which gives the NIH and others racing to produce a Zika vaccine a leg up. The Yellow fever vaccine, at 99 percent effectiveness, is one of the world’s most effective vaccines.

“I think we will wind up with an effective vaccine. I don’t want to be over confident,” Dr. Fauci  says. “The reason I say I believe that we will is because [Zika is] a flavivirus, and we have been able to develop effective flavivirus vaccines. Remember, Yellow fever is not too different from Zika.”

Laura Anthony and Lauren Kenworthy IMFAR

Tools for diverse populations with autism

Laura Anthony and Lauren Kenworthy IMFAR

Laura Anthony, Ph.D., and Lauren Kenworthy, Ph.D., from Children’s Center for Autism Spectrum Disorders shared their knowledge and research findings at the International Meeting for Autism Research.

Researchers, doctors and parents of autistic children seem to all agree on one truth: If you’ve met one child with autism, you’ve met one child with autism. That fact helps to explain why every spring, researchers and clinicians from around the world gather for the International Meeting for Autism Research (IMFAR) – it’s a key opportunity to connect with some of the most respected investigators and stakeholder partners in the research community, and to understand the similarities as well as the differences between autistic populations around the world. Through three days of keynote and panel discussions as well as hundreds of poster presentations on a variety of topics, IMFAR aims to exchange and disseminate the latest scientific and clinical progress in Autism Spectrum Disorders (ASD) to this global audience of scientists and trainees.

This year, ten faculty members, staff and volunteers from the Center for Autism Spectrum Disorders (CASD) at Children’s National attended IMFAR, and presented on a variety of topics related to better understanding the complex challenges of ASD, especially in diverse patient populations such as Latinos and young adults with gender dysphoria.

Laura Anthony, Ph.D., clinical psychologist within CASD, led a panel session entitled, “Addressing Disparities through Interventions in Diverse Community Systems,” which highlighted four community based intervention projects aimed at tackling the vast disparities that exist in screening, diagnosis, acceptance, inclusion and access to evidence-based care, based on populations.

“Each of these studies takes place in very different community contexts,” says Dr. Anthony, “but they share common themes of addressing disparities, using intensive stakeholder input and community partnerships to increase successful adoption, and achieving sustainability through harnessing the existing community-based resources to administer the interventions.”

The panel presentations featured studies from Children’s National as well as other research institutions:

  • Anthony’s co-investigation of the Sesame Workshop’s online tools called See Amazing in All Children and their effectiveness at providing useful education and resources for parents of children with ASD and at helping parents of non-ASD children feel more accepting of children on the spectrum.
  • Lauren Kenworthy, Ph.D., presented findings from the first study comparing two school-based cognitive-behavioral interventions developed by Children’s National and Ivymount, a school for children with autism, ADHD and other special needs. The interventions target executive function/problem solving and increase children’s availability for learning at school. As the interventions are provided by school staff in the school setting, they hold promise to reach the many children who otherwise have no access to specialized clinical care for these disorders. As evidence of this, approximately half of the children in this large scale project in low-income public/charter schools had not received a diagnosis of ADHD or autism prior to the study.
  • A study of the impacts of a stakeholder-informed primary care program to increase the rate of screening and referral for young Latino children (Georgetown University).
  • An analysis of one program’s efforts to increase the use of evidence-based practices in publically-funded mental health centers (University of California, San Diego; University of California, Los Angeles; and University of Illinois).
Allison Ratto Poster IMFAR

Allison Ratto, Ph.D., a clinical psychologist at the CASD, presented a poster entitled “Engaging Latino Families in ASD Treatment Research,” the first assessment of this type of effort to bring information and tools to Latino families in a way that makes them accessible.

Despite having vastly different designs, the panel also identified several common learned lessons from the studies. These include the amount of time required to build trusting relationships in previously neglected communities, and the need for creative and adaptive methodologies. Additionally, the importance of including individuals with ASD, their families and people in the community systems that serve them in stakeholder feedback sessions, and the need for specialized adaptations for each community’s unique needs.

Team members also presented ten research posters across a variety of specialty poster sessions, including Allison Ratto, Ph.D., a clinical psychologist at the CASD, who presented “Engaging Latino Families in ASD Treatment Research,” the first assessment of this type of effort to bring information and tools to Latino families in a way that makes them accessible.

“By developing an adaptive and flexible program, we were able to gain high levels of engagement from Latino families, who previously faced significant barriers to participation. The results show that if researchers take additional steps to build community trust and maintain stakeholder engagement, it is possible to recruit and retain study participants, and ultimately, meet the needs of underserved families.” Dr. Ratto concludes. Her poster was featured in a story in Spectrum News.

“IMFAR is definitely the premier opportunity to dialogue across disciplines and study methods,” says Dr. Kenworthy, who directs the CASD. “We hope that sharing our work at this prestigious meeting brings new understanding for our team and our colleagues in how to best meet the unique needs of psychologically, ethnically and economically diverse patients and families.”

Sarah Mulkey Columbia Zika Study

Damage may lurk in “normal” Zika-exposed brains

Sarah Mulkey Columbia Zika Study

An international study that includes Sarah B. Mulkey, M.D., Ph.D., aims to answer one of the most vexing questions about Zika: If babies’ brains appear “normal” at birth, have they survived Zika exposure in the womb with few neurological repercussions? Dr. Mulkey presented preliminary findings at PAS2017.

It has been well established by researchers, including scientists at Children’s National Health System, that the Zika virus is responsible for a slew of birth defects – such as microcephaly, other brain malformations and retinal damage – in babies of infected mothers. But how the virus causes these often devastating effects, and who exactly is affected, has not been explained fully.

Also unknown is whether exposed babies that appear normal at birth are truly unaffected by the virus or have hidden problems that might surface later. The majority of babies born to Zika-infected mothers in the United States appear to have no evidence of Zika-caused birth defects, but that’s no guarantee that the virus has not caused lingering damage.

Recently, Sarah B. Mulkey, M.D., Ph.D., made a trip to Colombia, where Children’s National researchers are collaborating on a clinical study. There, she tested Zika-affected babies’ motor skills as they sat, stood and lay facing upward and downward. The international study aims to answer one of the most vexing questions about Zika: If babies’ brains appear “normal” at birth, have they survived Zika exposure in the womb with few neurological repercussions?

“We don’t know the long-term neurological consequences of having Zika if your brain looks normal,” says Dr. Mulkey, a fetal-neonatal neurologist who is a member of Children’s Congenital Zika Virus Program. “That is what’s so scary, the uncertainty about long-term outcomes.”

According to the Centers for Disease Control and Prevention (CDC), one in 10 pregnancies across the United States with laboratory-confirmed Zika virus infection results in birth defects in the fetus or infant. For the lion’s share of Zika-affected pregnancies, then, babies’ long-term prospects remain a mystery.

“This is a huge number of children to be impacted and the impact, as we understand, has the potential to be pretty significant,” Dr. Mulkey adds.

Dr. Mulkey, the lead author, presented the research group’s preliminary findings during the 2017 annual meeting of the Pediatric Academic Societies (PAS). The presentation was one of several that focused on the Zika virus. Roberta L. DeBiasi, M.D., M.S., chief of the Division of Pediatric Infectious Diseases at Children’s National, organized two invited symposia devoted to the topic of Zika: Clinical perspectives and knowledge gaps; and the science of Zika, including experimental models of disease and vaccines. Dr. DeBiasi’s presentation included an overview of the 68 Zika-exposed or infected women and infants seen thus far by Children’s multidisciplinary Congenital Zika Virus Program.

“As the world’s largest pediatric research meeting, PAS2017 is an ideal setting for panelists to provide comprehensive epidemiologic and clinical updates about the emergence of Congenital Zika Syndrome and to review the pathogenesis of infection as it relates to the fetal brain,” Dr. DeBiasi says. “With temperatures already rising to levels that support spread of the Aedes mosquito, it is imperative for pediatricians around the world to share the latest research findings to identify the most effective interventions.”

As one example, Dr. Mulkey’s research sought to evaluate the utility of using magnetic resonance imaging (MRI) to evaluate fetal brain abnormalities in 48 babies whose mothers had confirmed Zika infection during pregnancy. Forty-six of the women/infant pairs enrolled in the prospective study are Colombian, and two are Washington, D.C. women who were exposed during travel to a Zika hot zone.

The women were infected with Zika during all three trimesters and experienced symptoms at a mean gestational age of 8.4 weeks. The first fetal MRIs were performed as early as 18 weeks’ gestation. Depending upon the gestational age when they were enrolled in the study, the participants had at least one fetal MRI as well as serial ultrasounds. Thirty-six fetuses had a second fetal MRI at about 31.1 gestational weeks. An experienced pediatric neuroradiologist evaluated the images.

Among the 48 study participants, 45 had “normal” fetal MRIs.

Three fetuses exposed to Zika in the first or second trimester had abnormal fetal MRIs:

  • One had heterotopia and an early, abnormal fold on the surface of the brain, indications that neurons did not migrate to their anticipated destination during brain development. This pregnancy was terminated at 23.9 gestational weeks.
  • One had parietal encephalocele, a rare birth defect that results in a sac-like protrusion of the brain through an opening in the skull. According to the CDC, this defect affects one in 12,200 births, or 340 babies, per year. It is not known if this rare finding is related to Zika infection.
  • One had a thin corpus callosum, dysplastic brainstem, heterotopias, significant ventriculomegaly and generalized cerebral/cerebellar atrophy.

“Fetal brain MRI detected early structural brain changes in fetuses exposed to the Zika virus in the first and second trimester,” Dr. Mulkey says. “The vast majority of fetuses exposed to Zika in our study had normal fetal MRI, however. Our ongoing study, underwritten by the Thrasher Research Fund, will evaluate their long-term neurodevelopment.”

Adré J. du Plessis, MB.Ch.B., M.P.H., director of the Fetal Medicine Institute and senior author of the paper, notes that this group “is a very important cohort to follow as long as Dr. Mulkey’s funding permits. We know that microcephaly is among the more devastating side effects caused by Zika exposure in utero. Unanswered questions remain about Zika’s impact on hearing, vision and cognition for a larger group of infants. Definitive answers only will come with long-term follow-up.”

Many of the Colombian families live in Sabanalarga, a relatively rural, impoverished area with frequent rain, leaving pockets of fresh water puddles that the mosquito that spreads Zika prefers, Dr. Mulkey adds. Families rode buses for hours for access to fetal MRI technology, which is not common in Colombia.

“The mothers are worried about their babies. They want to know if their babies are doing OK,” she says.

Breastfeeding Mom

Breast milk helps white matter in preemies

Breastfeeding Mom

Critical white matter structures in the brains of babies born prematurely at low birth weight develop more robustly when their mothers breast-feed them, compared with preemies fed formula.

Breast-feeding offers a slew of benefits to infants, including protection against common childhood infections and potentially reducing the risk of chronic health conditions such as asthma, obesity and type 2 diabetes. These benefits are especially important for infants born prematurely, or before 37 weeks gestation – a condition that affects 1 in 10 babies born in the United States, according to the Centers for Disease Control and Prevention. Prematurely born infants are particularly vulnerable to infections and other health problems.

Along with the challenges premature infants face, there is a heightened risk for neurodevelopmental disabilities that often do not fully emerge until the children enter school. A new study by Children’s National Health System researchers shows that breast-feeding might help with this problem. The findings, presented at the 2017 annual meeting of the Pediatric Academic Societies, show that critical white matter structures in the brains of babies born so early that they weigh less than 1,500 grams develop more robustly when their mothers breast-feed them, compared with preemie peers who are fed formula.

The Children’s National research team used sophisticated imaging tools to examine brain development in very low birth weight preemies, who weighed about 3 pounds at birth.

They enrolled 37 babies who were no more than 32 weeks gestational age at birth and were admitted to Children’s neonatal intensive care unit within the first 48 hours of life. Twenty-two of the preemies received formula specifically designed to meet the nutritional needs of infants born preterm, while 15 infants were fed breast milk. The researchers leveraged diffusion tensor imaging – which measures organization of the developing white matter of the brain – and 3-D volumetric magnetic resonance imaging (MRI) to calculate brain volume by region, structure and tissue type, such as cortical gray matter, white matter, deep gray matter and cerebellum.

“We did not find significant differences in the global and regional brain volumes when we conducted MRIs at 40 weeks gestation in both groups of prematurely born infants,” says Catherine Limperopoulos, Ph.D., director of the Developing Brain Research Laboratory and senior author of the paper. “There are striking differences in white matter microstructural organization, however, with greater fractional anisotropy in the left posterior limb of internal capsule and middle cerebellar peduncle, and lower mean diffusivity in the superior cerebellar peduncle.”

White matter lies under the gray matter cortex, makes up about half of the brain’s volume, and is a critical player in human development as well as in neurological disorders. The increased white matter microstructural organization in the cerebral and cerebellar white matter suggests more robust fiber tracts and microarchitecture of the developing white matter which may predict better neurologic outcomes in preterm infants. These critical structures that begin to form in the womb are used for the rest of the person’s life when, for instance, they attempt to master a new skill.

“Previous research has linked early breast milk feeding with increased volumetric brain growth and improved cognitive and behavioral outcomes,” she says. “These very vulnerable preemies already experience a high incidence rate of neurocognitive dysfunction – even if they do not have detectable structural brain injury. Providing them with breast milk early in life holds the potential to lessen those risks.”

The American Academy of Pediatrics endorses breast-feeding because it lowers infants’ chances of suffering from ear infections and diarrhea in the near term and decreases their risks of being obese as children. Limperopoulos says additional studies are needed in a larger group of patients as well as longer-term follow up as growing infants babble, scamper and color to gauge whether there are differences in motor skills, cognition and writing ability between the two groups.

Catherine Limperopoulous

The brain’s fluid-filled spaces during growth

Catherine Limperopoulous

Catherine Limperopoulous, Ph.D., and her colleagues used volumetric MRIs to assess how the ventricles, cerebrospinal fluid and the rest of the fetal brain normally change over time.

The human brain is not one solid mass. Buried within its gray and white matter are a series of four interconnected chambers, called ventricles, which produce cerebrospinal fluid. These ventricles are readily apparent on the fetal ultrasounds that have become the standard of prenatal care in the United States and most developed countries around the world. Abnormalities in the ventricles’ size or shape – or both – can give doctors an early warning that fetal brain development might be going awry.

But what is abnormal? It is not always clear, says Catherine Limperopoulos, Ph.D., director of the Developing Brain Research Laboratory at Children’s National Health System. Limperopoulos explains that despite having many variations in fetal ventricles, some infants have completely normal neurodevelopmental outcomes later. On the other hand, some extremely subtle variations in shape and size can signal problems.

On top of these complications are the tools clinicians typically use to assess the ventricles. Limperopoulos explains that most early indications of ventricle abnormalities come from ultrasounds, but the finer resolution of magnetic resonance imaging (MRI) can provide a more accurate assessment of fetal brain development. Still, both standard MRI and ultrasound provide only two-dimensional pictures, making it difficult to quantify slight differences in the volume of structures.

To help solve these problems, Limperopoulos and her colleagues recently published a paper in Developmental Neuroscience that takes a different tack. The team performed volumetric MRIs – a technique that provides a precise three-dimensional measure of structural volumes – on the brains of healthy fetuses to assess how the ventricles, cerebrospinal fluid and the rest of the brain normally change over time. Limperopoulos’ team recently performed a similar study to assess normal volumetric development in the brain’s solid tissues.

Previous studies published on comparable topics typically used information gathered from subjects who initially had clinical concerns but eventually were dismissed from these studies for not having worrisome diagnoses in the end. This might not truly reflect a typical population of pregnant women, Limperopoulos says.

Working with 166 pregnant women with healthy pregnancies spanning from 18 to 40 weeks gestation, the researchers performed volumetric MRIs on their singleton fetuses that covered every week of this second half of pregnancy. This technique allowed them to precisely calculate the volumes of structures within the fetal brain and get an idea of how these volumes changed over time within the group.

Their results show that over the second and third trimester:

  • The lateral ventricles, the largest ventricles found in the cerebrum with one for each brain hemisphere, grew about two-fold;
  • The third ventricle, found in the forebrain, grew about 23-fold;
  • The fourth ventricle, found in the hindbrain, grew about eight-fold;
  • And the extra-axial cerebrospinal fluid, found under the lining of the brain, increased about 11-fold.

The total brain volume increased 64-fold over this time, with the parenchyma – the solid brain tissue that encompasses gray and white matter – growing significantly faster than the cerebrospinal fluid-filled spaces.

Limperopoulos points out that the ability to measure the growth of the brain’s fluid-filled spaces relative to the surrounding brain tissue can provide critical information to clinicians caring for developing fetuses. In most cases, knowing what is normal allows doctors to reassure pregnant women that their fetus’ growth is on track. Abnormalities in these ratios can provide some of the first signals to alert doctors to blockages in cerebrospinal fluid flow, abnormal development, or the loss of brain tissue to damage or disease. Although the neurodevelopmental outcomes from each of these conditions can vary significantly, traditional ultrasounds or MRIs might not be able to distinguish these possibilities from each other. Being able to differentiate why cerebrospinal fluid spaces have abnormal shapes or sizes might allow doctors to better counsel parents, predict neurological outcomes, or potentially intervene before or after birth to mitigate brain damage.

“By developing a better understanding of what’s normal,” Limperopoulos says, “we can eventually identify reliable biomarkers of risk and guide interventions to minimize risks for vulnerable fetuses.”