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Sarah Mulkey

MRI and ultrasound imaging detect the spectrum of Zika’s impact

Sarah Mulkey

“A combination of prenatal MRI and US was able to detect Zika-related brain abnormalities during pregnancy, giving families timely information to prepare for the potential complex care needs of these infants,” says Sarah B. Mulkey, M.D., Ph.D.

Worldwide, thousands of babies have been born to mothers who were infected during pregnancy with Zika, a virus associated with neurological deficits, impaired vision and neurodevelopmental disabilities, among other birth defects. These birth defects are sometimes severe, causing lifelong disability. But they’re also relatively rare compared with the overall rates of infection.

Predicting how many Zika-exposed babies would experience neurological birth defects has been challenging.

However, an international study led by Children’s faculty suggests that ultrasound (US) imaging performed during pregnancy and after childbirth revealed most Zika-related brain abnormalities experienced by infants exposed to the Zika virus during pregnancy, according to a prospective cohort study published online Nov. 26, 2018, in JAMA Pediatrics. Some Zika-exposed infants whose imaging had been normal during pregnancy had mild brain abnormalities detected by US and magnetic resonance imaging (MRI) after they were born.

“A combination of prenatal MRI and US was able to detect Zika-related brain abnormalities during pregnancy, giving families timely information to prepare for the potential complex care needs of these infants,” says Sarah B. Mulkey, M.D., Ph.D., a fetal-neonatal neurologist at Children’s National Health System and the study’s lead author. “In our study, we detected mild brain abnormalities on postnatal neuroimaging for babies whose imaging was normal during pregnancy. Therefore, it is important for clinicians to continue to monitor brain development for Zika-exposed infants after birth.”

As of Nov. 20 2018, nearly 2,500 pregnant women in the U.S. had laboratory confirmed Zika infection, and about 2,400 of them had given birth, according to the Centers for Disease Control and Prevention (CDC). While more than 100 U.S. infants were born with Zika-associated birth defects, the vast majority of Zika-exposed U.S. infants were apparently normal at birth. The sequential neuroimaging study Dr. Mulkey leads seeks to determine the spectrum of brain findings in infants exposed to Zika in the womb using both US and MRI before and after birth.

The international research team enrolled 82 women in the study from June 15, 2016, through June 27, 2017. All of the women had been exposed to Zika during pregnancy; all but one experienced clinical symptoms by a mean gestational age of 8.2 weeks. Eighty of those women lived in or near Barranquilla, Colombia, and were exposed to Zika there. Two U.S. study participants were exposed to the primarily mosquito-borne illness during travel to Zika hot zones.

All women received fetal MRIs and US during the second and/or third trimester of pregnancy. After their infants were born, the children received brain MRI and cranial US. Blood samples from both mothers and babies were tested for Zika using polymerase chain reaction and serology.

Fetal MRI was able to discern Zika-related brain damage as early as 18 weeks gestation and picked up significant fetal brain abnormalities not fully appreciated in US imaging. In one case, the US remained normal while fetal MRI alone detected brain abnormalities. Three fetuses (4 percent) had severe fetal brain abnormalities consistent with Zika infection, including:

Seventy-five infants were born at term. One pregnancy was terminated at 23 weeks gestation due to the gravity of the fetal brain abnormalities. One fetus with normal imaging died during pregnancy. One newborn who was born with significant fetal brain abnormalities died at age 3 days.

Cranial US and brain MRI was performed on the majority of infants whose prenatal imaging had been normal.  Seven of 53 (13 percent) Zika-exposed infants had mild brain abnormalities detected by MRI after birth. In contrast, postnatal cranial US was better at detecting changes of lenticulostriate vasculopathy, cysts within the brain’s choroid plexus (cells that produce cerebrospinal fluid), germinolytic/subependymal cysts and/or calcifications, which were seen in 21 of 57 (37 percent) infants.

“Sequential neuroimaging revealed that the majority of Zika-exposed fetuses had normal brain development. Tragically, in a small number of pregnancies, Zika-related brain abnormalities were quite severe,” Dr. Mulkey adds. “Our data support the CDC’s recommendation that cranial US be performed after Zika-exposed babies are born. In addition, there is clearly a need to follow these babies over time to gauge whether the brain anomalies we see in imaging affects language, motor and social skills.”

Companion editorial: Revealing the effects of Zika

In addition to Dr. Mulkey, study co-authors include Dorothy I. Bulas, M.D.Gilbert Vezina, M.D., Margarita Arroyave-Wessel, MPH,  Stephanie Russo, B.S, Youssef A. Kousa, D.O, Ph.D.Roberta L. DeBiasi, M.D., MS, Senior Author Adré J. du Plessis, M.B.Ch.B., MPH, all of Children’s National; Christopher Swisher, BS, Georgetown University and Caitlin Cristante, BS, Loyola University, both of  whose contributions included research performed at Children’s National; Yamil Fourzali, M.D., Armando Morales, M.D., both of Sabbag Radiologos; Liliana Encinales, M.D., Allied Research Society; Nelly Pacheco, Bacteriologa, Bio-Nep; Robert S. Lanciotti, Ph.D., Arbovirus Diseases Branch, Centers for Disease Control and Prevention; and Carlos Cure, M.D., BIOMELAB.

Research reported in this news release was supported by the IKARIA fund.

Dorothy Bulas

Dorothy Bulas, M.D., receives the Society for Pediatric Radiology’s highest honor

Dorothy Bulas

Dorothy Bulas, M.D. F.A.C.R., F.A.I.U.M., F.S.R.U., chief of diagnostic imaging and radiology in the Division of Diagnostic Imaging and Radiology at Children’s National Health System, is being recognized at the 2018 Society for Pediatric Radiology Annual Meeting with their most distinguished honor, the Gold Medal.

The Society of Pediatric Radiology (SPR) Gold Medal is awarded to pediatric radiologists who have contributed greatly to the SPR and their subspecialty of pediatric radiology as a scientist, teacher, personal mentor and leader.

Initially, Dr. Bulas completed her residency in pediatrics. During a pediatric radiology rotation at John Hopkins University, she realized how much she loved problem solving and using emerging imaging modalities and went on to complete her radiology residency at Albert Einstein Hospital. Soon after, Dr. Bulas moved to Washington, D.C. to complete a pediatric radiology fellowship at her professional home, Children’s National.

Since the completion of her fellowship, Dr. Bulas views her role in the advancement of fetal imaging as her most significant professional contribution. She has published 131 papers, one of her most recent as a co-author on “Neuroimaging findings in normocephalic infants with Zika virus” in Pediatric Neurology. Dr. Bulas is also a co-author of the textbook entitled Fundamental and Advanced Fetal Imaging and has authored 35 book chapters.

She has served as program director of the Radiology Fellowship Program at Children’s National since 2005 where she has impacted medical students, residents and fellows from the United States and abroad.

As a previous chair member for numerous organizations, Dr. Bulas currently co-chairs the American College of Radiology’s pediatric radiology education committee. She is a founding member of the Image Gently Alliance, where she chaired the outreach campaign to parents and wrote brochures, web material and articles. Dr. Bulas is also a founder of the World Federation of Pediatric Imaging.

Dr. Bulas was honored as an outstanding teacher with the Edward Singleton-Hooshang Taybi Award for Excellence in Education from the SPR and this past fall and as the Outstanding Educator in 2017 by the Radiological Society of North America.

Dorothy Bulas

Congratulations to Dorothy Bulas, M.D. – 2017 RSNA Outstanding Educator recipient

Dorothy Bulas

Dorothy Bulas, M.D., section head of ultrasound and fetal imaging at Children’s National Health System, was honored with the RSNA 2017 Outstanding Educator award at the Radiological Society of North America’s (RSNA) Annual Meeting, held November 26 – December 1 in Chicago, Illinois.

The winner of the award is selected annually by the RSNA Board of Directors based on the awardee’s significant contributions and long-term commitment – 15 years or more – to radiologic education.

“In addition to being a talented clinician and an accomplished researcher, Dr. Bulas is an extraordinary teacher who has made tireless contributions to the educational programs of RSNA,” said RSNA President Richard L. Ehman, M.D. “For more than three decades, she has been a passionate and effective advocate for improving pediatric radiology worldwide – especially in poorly served countries – by participating in educational outreach.”

Children’s National earns five awards at the 2017 SPR Annual Meeting

Radiology PULSE Suite

Several technologists, fellows and faculty in the Division of Diagnostic Imaging and Radiology at Children’s National Health System were recognized at the 2017 Society of Pediatric Radiology (SPR) Annual Meeting in Vancouver, Canada, May 16-20. Each year, the international conference recognizes society members for outstanding research and education in pediatric care on the topics of imaging and image-guided care. Out of 15 major awards, Children’s National staff earned five, including two Caffey Awards – SPR’s most prestigious awards for academic excellence.

The awards received are as follows:

The Society of Pediatric Radiology Caffey Award for Best Clinical Research Paper went to attending radiologist, Dorothy Bulas, M.D., for her clinical research paper titled, “CXR Reduction Protocol in the Neonatal Intensive Care Unit (NICU) – Lessons Learned,” which highlighted collaboration with the NICU team to reduce the reliance on x-rays to monitor neonates. This method decreases the radiation dose with no risk to the patient.

The Society of Pediatric Radiology Caffey Award for Educational Exhibit was given to Benjamin Smith, M.D., a pediatric radiology fellow, for his educational poster “Sonographic Evaluation of Diaphragmatic Motion: A Practical Guide to Performance and Interpretation.” The exhibit displayed a unique technique for examining the motion of the diaphragm using ultrasound to make an accurate diagnosis of diaphragm paralysis or motion. Dr. Smith’s exhibit was also recognized by The American Academy of Pediatrics and was given the Outstanding Clinical Education Poster Award along with radiologist Hansel Otero, M.D.; sonographer Tara K. Cielma, R.D.M.S, R.D.C.S, R.V.T.; and faculty member Anjum N. Bandarkar, M.D.

The Society of Pediatric Radiology Radiographer Best Poster Award was given to Dr. Bandarkar for her poster titled, “Infantile Hypertrophic Pyloric Stenosis: Value of measurement technique to avoid equivocal exam.” The World Federation of Pediatric Imaging also awarded Dr. Bandarkar, Adebunmi O. Adeyiga, M.D. and Tara Cielma the 2017 Outstanding Radiographer Educational Poster Award for their collaborative poster on, “A Sonographic Walk‐Through: Infantile Hypertrophic Pyloric Stenosis.”

Division Chief of Diagnostic Imaging and Radiology, Raymond Sze, M.D., remarked, “This is a major win not only for the department but also for the entire hospital. The support and collaboration of our Children’s National colleagues across many departments allowed us to advance the field of pediatric imaging and earn national recognition for the high-quality and impactful research and education that’s happening at our institution.”

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.

Drs. DeBiasi and du Plessis

Zika virus, one year later

Drs. DeBiasi and du Plessis

A multidisciplinary team at Children’s National has consulted on 66 Zika-affected pregnancies and births since May 2016.

The first pregnant patient with worries about a possible Zika virus infection arrived at the Children’s National Health System Fetal Medicine Institute on Jan. 26, 2016, shortly after returning from international travel.

Sixteen months ago, the world was just beginning to learn how devastating the mosquito-borne illness could be to fetuses developing in utero. As the epidemic spread, a growing number of sun-splashed regions that harbor mosquitoes that efficiently spread the virus experienced a ballooning number of Zika-affected pregnancies and began to record sobering birth defects.

The Washington, D.C. patient’s concerns were well-founded. Exposure to Zika virus early in her pregnancy led to significant fetal brain abnormalities, and Zika virus lingered in the woman’s bloodstream months after the initial exposure — longer than the Centers for Disease Control and Prevention (CDC) then thought was possible.

The research paper describing the woman’s lengthy Zika infection, published by The New England Journal of Medicine, was selected as one of the most impactful research papers written by Children’s National authors in 2016.

In the intervening months, a multidisciplinary team at Children National has consulted on 66 pregnancies and infants with confirmed or suspected Zika exposure. Thirty-five of the Zika-related evaluations were prenatal, and 31 postnatal evaluations assessed the impact of in utero Zika exposure after the babies were born.

The continuum of Zika-related injuries includes tragedies, such as a 28-year-old pregnant woman who was referred to Children’s National after imaging hinted at microcephaly. Follow-up with sharper magnetic resonance imaging (MRI) identified severe diffuse thinning of the cerebral cortical mantle, evidence of parenchymal cysts in the white matter and multiple contractures of upper and lower extremities with muscular atrophy.

According to a registry of Zika-affected pregnancies maintained by the CDC, one in 10 pregnancies across the United States with laboratory-confirmed Zika virus infection has resulted in birth defects in the fetus or infant.

“More surprising than that percentage is the fact that just 25 percent of infants underwent neuroimaging after birth – despite the CDC’s recommendation that all Zika-exposed infants undergo postnatal imaging,” says Roberta L. DeBiasi, M.D., M.S., chief of the Division of Pediatric Infectious Diseases and co-director of the Congenital Zika Virus Program at Children’s National. “Clinicians should follow the CDC’s guidance to the letter, asking women about possible exposure to Zika and providing multidisciplinary care to babies after birth. Imaging is an essential tool to accurately monitor the growing baby’s brain development.”

Adré du Plessis, M.B.Ch.B., M.P.H., director of the Fetal Medicine Institute and Congenital Zika Virus Program co-leader, explains the challenges: ”When it comes to understanding the long-term consequences for fetuses exposed to the Zika virus, we are still on the steepest part of the learning curve. Identifying those children at risk for adverse outcomes will require a sustained and concerted multidisciplinary effort from conception well beyond childhood.”

In addition to counseling families in the greater Washington, D.C. region, the Children’s research team is collaborating with international colleagues to conduct a clinical trial that has been recruiting Zika-infected women and their babies in Colombia. Pediatric Resident Youssef A. Kousa, D.O., Ph.D., M.S., and Neurologist Sarah B. Mulkey, M.D., Ph.D., will present preliminary findings during Research and Education Week 2017.

In Colombia as well as the District of Columbia, a growing challenge continues to be assessing Zika’s more subtle effects on pregnancies, developing fetuses and infants, says Radiologist Dorothy Bulas, M.D., another member of Children’s multidisciplinary Congenital Zika Virus Program.

The most severe cases from Brazil were characterized by interrupted fetal brain development, smaller-than-normal infant head circumference, brain calcifications, enlarged ventricles, seizures and limbs folded at odd angles. In the United States and many other Zika-affected regions, Zika-affected cases with such severe birth defects are outnumbered by infants who were exposed to Zika in utero but have imaging that appears normal.

In a darkened room, Dr. Bulas pores over magnified images of the brains of Zika-infected babies, looking for subtle differences in structure that may portend future problems.

“There are some questions we have answered in the past year, but a number of questions remain unanswered,” Dr. Bulas says. “For neonates, that whole area needs assessment. As the fetal brain is developing, the Zika virus seems to affect the progenitor cells. They’re getting hit quite early on. While we may not detect brain damage during the prenatal period, it may appear in postnatal images. And mild side effects that may not be as obvious early on still have the potential to be devastating.”

Mary Donofrio

Getting to the heart of cardiac malposition with fetal MRI

Mary T. Donofrio, MD, Director of the Fetal Heart Program and Critical Care Delivery Program at Children's National Health System

Mary T. Donofrio, M.D., Director of the Fetal Heart Program and Critical Care Delivery Program at Children’s National Health System

In a small percentage of pregnancies, the fetuses’ hearts develop in the wrong place. In the congenital anomaly known as heterotaxy syndrome that often includes a severe heart defect, the heart is often displaced from its usual position in the left chest. In other instances, the heart starts out in a normal position; however, it is pushed out of its normal position by a mass that grows in the chest cavity, by abnormal development of the lungs, or due to other causes. Although rare, babies born with cardiac malpositions associated with other congenital defects can be the most serious of all possible birth defects.

Sometimes, fetuses with these congenital problems die in the womb. Others do not survive long after birth. In some pregnancies, surgery is performed shortly after childbirth to stabilize the circulation so newborns even have a chance at life.

Correctly diagnosing these cardiac conditions during pregnancy can help doctors and parents alike make the most informed decisions and plan ahead.

However, the tools now used most often to reveal the overall anatomic details of cardiac malpositions — obstetrical ultrasound and fetal echocardiography — often don’t give a full picture. A clear view of the fetus can be obscured by the position of the fetus, insufficient amniotic fluid, or even a mother’s body habitus. Imaging techniques sometimes also have a hard time distinguishing between liver, bowel, and lung because the echogenicity of these tissues — the signature that sound waves make as they bounce back from their targets — is so similar.

“To be able to offer parents the best and most comprehensive counseling, and to begin planning for the type of intensive and multidisciplinary care that many of these babies will require, we need to have access to as much information as we can about each baby, not only relating to the heart but all the other organs as well,” says Mary T. Donofrio, M.D., a pediatric cardiologist who directs the Children’s National Health System Fetal Heart Program and Critical Care Delivery Program. “Unfortunately in some instances, obstetrical ultrasound and fetal echocardiography, the two diagnostic tools used most often in these cases, can be limited in what they tell us.”

What fetal MRI can show

An underutilized technique that gathers more details about the associated abnormalities that often accompany cardiac malposition during pregnancy is fetal magnetic resonance imaging, or fetal MRI, says Dr. Donofrio. Even though this technique is widely used to diagnose other fetal conditions, such as brain anomalies, it’s rarely used to better define the overall anatomy in cardiac malposition.

To determine whether fetal MRI is effective in complementing obstetrical ultrasound and fetal echocardiography, the current standard of care for this condition, Dr. Donofrio and colleagues took a retrospective look at all cases of cardiac malposition in which fetuses were evaluated using MRI between 2008 to 2013 at Children’s National. Their search turned up 42 cases.

Twenty-three cases had been diagnosed with obstetrical ultrasound and fetal echocardiography as having additional abnormalities beyond the heart’s changed position, and 19 had been given the diagnosis of heterotaxy syndrome. Each patient had been assigned to various known subtypes of these conditions, with some classified as having an unknown etiology for the findings.

After fetal MRI, the diagnoses of nearly one-third changed or were better delineated. Seven of the 23 cases of cardiac malposition attributed to an extra cardiac anomaly were reassigned to a cause different from the original diagnosis based on the new, more detailed information provided by fetal MRI, including three in which a complete diagnosis could not be made due to poor visualization by ultrasound. Five of the 19 cases attributed of heterotaxy were reassigned to different subgroups within this disorder or were given a different diagnosis completely after fetal MRI.

In eight of these 12 diagnoses that changed after fetal MRI, doctors were able to confirm these findings postnatally. Other cases were either lost to follow-up, pregnancy termination, or fetal demise.

The research team led by Dr. Donofrio published these results in the August 2016 issue of Prenatal Diagnosis.

Overall, she says the findings demonstrated the benefits of using fetal MRI as an adjunct to obstetrical ultrasound and fetal echocardiography. MRI offers advantages over ultrasound, she explains, including better spatial resolution, a wider field of view, and a way to see through or around maternal body fat, overlying fetal bone, or a fetus whose position is not optimal.

“Determining the etiology of cardiac malposition remains a challenging diagnosis, and the value of accurate prenatal diagnosis has been long recognized,” Donofrio and colleagues write in the study. “Ultimately, fetal MRI can assist with identifying the etiology of cardiac malposition for informative prenatal counseling and multidisciplinary planning.”

Catherine Limperopoulos

Connection between abnormal placenta and impaired growth of fetuses discovered

CLimperopoulous

A team of researchers used 3-D volumetric magnetic resonance imaging (MRI) in an innovative study that reported that when the placenta fails to grow adequately in a fetus with congenital heart disease (CHD), it contributes to impaired fetal growth and premature birth. Fetal CHD involves an abnormality of the heart and is associated with increased risk for neurodevelopmental morbidity.Until now, CHD in the fetus and its relationship to placental function has been unknown. But the advanced fetal imaging study has shown for the first time that abnormal growth in the fetus with CHD relates to impaired placental growth over the third trimester of pregnancy. Catherine Limperopoulos, PhD, Director of Children’s National Developing Brain Research Laboratory in the Division of Diagnostic Imaging and Radiology, is the senior author of the study published in the September 2015 issue of the journal Placenta, “3-D Volumetric MRI Evaluation of the Placenta in Fetuses With Complex Heart Disease.”

Specifically, the decreased 3-D volumetric MRI measurements of pregnant women reported in this study suggest placental insufficiency related to CHD. The placenta nourishes and maintains the fetus, through the delivery of food and oxygen. Its volume and weight can determine fetal growth and birth weight.

Abnormality in placental development may contribute to significant morbidity in this high risk-population. This study shows impaired placental growth in CHD fetuses is associated with the length of the pregnancy and weight at birth. Nearly 1 in every 100 babies is born in the United States with a congenital heart defect.

Developing the capacity to examine the placenta non-invasively using advanced MRI is needed to identify early markers of impaired placental structure and function in the high-risk pregnancy. This is a critical first step towards developing strategies for improved fetal monitoring and management, Dr. Limperopoulos says.

“We are trying to develop the earliest and most reliable indicators of placental health and disease in high-risk pregnancies. Our goal is to bring these early biomarkers into clinical practice and improve our ability to identify placental dysfunction,” Dr. Limperopoulos says. “If we can develop the capacity to reliably identify when things begin to veer off course, we then have a window of opportunity to develop therapies to restore function.”

The study used in-vivo 3-D MRI studies and explored placental development and its relationship to neonatal outcomes by comparing placental volumetric growth in healthy pregnancies and pregnancies complicated by CHD.

While mortality rates continue to decrease steadily in newborns diagnosed with complex CHD, long-term neurodevelopmental impairments are recognized with increasing frequency in surviving infants, Dr. Limperopoulos says.

“Our goal is to better support the developing fetus with CHD. We can best accomplish this if we develop technology that can allow us to safely and effectively monitor the fetal-placental unit as a whole throughout pregnancy,” Dr. Limperopoulos says.

“This is the new frontier, not only to ensure survival but to safeguard the fetus and to ensure the best possible quality of life,” she says.