Tag Archive for: imaging

data science illustration

Federated learning: A solution to AI’s data-sharing challenges

data science illustration

Federated learning can solve data-sharing challenges, allowing nimble collaboration across institutions to drive medical advances using artificial intelligence (AI).

Federated learning can solve data-sharing challenges, allowing nimble collaboration across institutions to drive medical advances using artificial intelligence (AI), according to a new manuscript from 10 thought leaders in AI and machine learning in medicine.

In Health Informatics Journal, these leading experts on how technology is shaping medicine shared a conversation that they had at the Radiology Society of North America’s conference. They weighed challenges facing AI, including barriers to data sharing because of privacy rules that prevent the distribution of information to different institutions. With federated learning, models are shared – rather than data – allowing institutions to aggregate information and collaborate with a master model.

“Federated learning offers tremendous promise,” said Marius George Linguraru, D.Phil., M.A., M.Sc., the Connor Family Professor of Research and Innovation, principal investigator at the Sheikh Zayed Institute of Pediatric Surgical Innovation and senior author on the manuscript. “As a community of experts, we have found that federated learning allows us to move away from the challenges of sharing data in central repositories. Instead, we share the models, which can be designed to protect privacy by limiting what’s shared outside of any given institution.”

A champion of pediatric health, Linguraru wants to ensure that children are represented in the development of models that advance science and medicine. “Sharing data is even more crucial when there are few patients, such as in rare diseases or pediatric populations,” he said. “In general, healthcare data suffers from inequitable representation in our public health systems and services.”

Learn more here about the challenges and potential solutions from experts at Rhino Health, Johns Hopkins University School of Medicine, NVIDIA, University of Cambridge, Ben-Gurion University Israel, MD Anderson Cancer Center, Dana-Farber Cancer Institute and Children’s National Hospital.

AI chip illustration

How radiologists and data scientists can collaborate to advance AI in clinical practice

AI chip illustration

The scientific community continues to debate AI’s possibility of outperforming humans in specific tasks. In the context of the machine’s performance versus the clinician, Linguraru et al. argue that the community must consider social, psychological and economic contexts in addition to the medical implications to answer this puzzling question.

In a special report published in Radiology: Artificial Intelligence, a Children’s National Hospital expert and other institutions discussed a shared multidisciplinary vision to develop radiologic and medical imaging techniques through advanced quantitative imaging biomarkers and artificial intelligence (AI).

“AI algorithms can construct, reconstruct and interpret radiologic images, but they also have the potential to guide the scanner and optimize its parameters,” said Marius George Linguraru, D.Phil., M.A., M.Sc., principal investigator in the Sheikh Zayed Institute for Pediatric Surgical Innovation at Children’s National. “The acquisition and analysis of radiologic images is personalized, and radiologists and technologists adapt their approach to every patient based on their experience. AI can simplify this process and make it faster.”

The scientific community continues to debate AI’s possibility of outperforming humans in specific tasks. In the context of the machine’s performance versus the clinician, Linguraru et al. argue that the community must consider social, psychological and economic contexts in addition to the medical implications to answer this puzzling question.

Still, they believe that developing a useful radiologic AI system designed with the participation of radiologists could complement and possibly surpass human’s interpretation of the visuals.

Given AI’s potential applications, the authors encouraged radiologists to access many freely available resources to learn about machine learning, and radiomics to familiarize with basic concepts. Coursera, for example, can teach radiologists about convolutional neural networks and other techniques used by AI researchers.

Conversely, AI experts must reach out to radiologists and participate in public speaking events about their work. According to the researchers, during those engagement opportunities, clinicians understood the labor-saving benefits of automatic complex measurements on millions of images—something that they have been doing manually for years.

There are also hurdles around this quest of automation, which Linguraru et al. hope both fields can sort out by working together. A critical challenge that the experts mentioned was earning the trust of clinicians that are skeptical about the “black box” functionality of AI models, which makes it hard to understand and explain the behavior of a model.

Some questions, too, need answers on how to best leverage both human intelligence and AI by using human-in-the-loop where people train, tune, and test a particular algorithm, or AI in-the-loop where this different framing generates AI input and reflection in human systems.

“The key is to have a good scientific premise to adequately train and validate the algorithms and make them clinically useful. At that point, we can trust the box,” said Linguraru. “In radiology, we should focus on AI systems with radiologists in-the-loop, but also on training radiologists with AI in-the-loop, particularly as AI systems are getting smarter and learning to work better with radiologists.”

The experts also provided possible solutions to sharing large datasets, how to build datasets that allows robust investigations and how to improve the quality of a model that might be compared against human’s gold standard.

This special report is the second in a series of panel discussions hosted by the Radiological Society of North America and the Medical Image Computing and Computer Assisted Intervention Society. The discussion builds upon the first in the series “Machine Learning for Radiology from Challenges to Clinical Applications” that touched on how to incentivize annotators to participate in projects, the promotion of “team science” to address research questions and challenges, among other topics.

multimodal imaging images

Real-time surgical guidance system enables multimodal tissue monitoring

For the first time, researchers at Children’s National Hospital successfully demonstrated a label-free tissue perfusion imaging in a pre-clinical model, according to a study published in IEEE Transactions on Biomedical Engineering.

Richard Jaepyeong Cha, Ph.D., research faculty associate professor at Children’s National, and colleagues combined visible, near-infrared laser speckle contrast imaging (LSCI) and snapshot hyperspectral (HSI) cameras into a single clinical multimodal imaging device suitable for real-time intraoperative visualization and demonstrated such a device in a surgical model for the first time, to the best knowledge of the authors. This system provides instant microcirculation information about the ischemic regions, normal tissue and transitional ischemic zones with quantitative values that are reproducible.

“Our pre-clinical work demonstrated a novel, dye-free imaging platform for quantitatively assessing bowel perfusion. The ability to identify optimal surgical resection margins can improve surgical performance and patient outcome in terms of more targeted bowel resection and bowel preservation without anastomotic leakage,” Cha said. “This new optical imaging and quantitative assessment technology holds great promise to solving the long-standing issue of suboptimal assessment of intestinal viability.”

Intraoperative imaging techniques for the precise monitoring of blood flow, hemorrhage and oxygen saturation are needed to minimize errors caused by blood vessel ligation to reduce surgical blood loss and successfully isolate and resect ischemic regions.

When the blood flow, hemorrhage and oxygen are not monitored properly, anastomotic leak (AL) is a serious complication of intestinal surgery that can occur due to a technical error, and most frequently because of poorly vascularized intestine.

This complication of intestinal surgery carries with it a reported mortality ranging from 6 to 39%. The best time to prevent a possible AL is during its creation in the operating room.

Creating a healthy and safe intestinal anastomosis requires a good blood supply to the two ends of bowel to be joined. The tools for diagnosing well-perfused bowel intraoperatively are limited and often rely on the subjective evaluation of the surgeon.

“We are hoping that the use and application of multimodal LSCI/HSI imaging, capable of both non-invasive and quantitative gross tissue perfusion assessment, will provide colorectal/general surgeons with a convenient and objective method for assessment of bowel perfusion characteristics and facilitate surgical transection in tissues requiring colorectal anastomosis,” Cha said.

Recently, indocyanine green fluorescence angiography (ICG-FA) was introduced for intraoperative assessment of anastomotic perfusion. Preliminary evidence suggests that ICG-FA may reduce the rate of anastomotic leakage in gastrointestinal surgery.

Perfusion assessment at the site of anastomosis may alter surgical strategy and possibly reduce anastomotic leakage rates. However, ICG-FA evaluation requires an exogenous fluorophore and the surgeon must subjectively assess the quality of perfusion. For an ideal intestinal viability test, it is essential that the technique is easily performed by the surgeon, minimally invasive, objective and reproducible—which is what Lee et al. demonstrate with their new approach.

multimodal imaging system

The hybrid tracking mount for the LUS transducer

New hybrid approach for AR visualization of ultrasound images has surgical use

Children’s National Hospital researchers combined augmented reality (AR) and ultrasound imaging technologies to improve visualization during laparoscopic procedures. The patent-pending hybrid tracking method improved accuracy compared with hardware-based and computer vision-based approaches, according to the pre-clinical study published in the Journal of Medical Imaging.

“The system that we developed can work reliably under challenging intraoperative conditions, which is exciting for us,” said Raj Shekhar, M.S., Ph.D., principal investigator at Children’s National and senior author in the study. “The surgical view is usually very complex with various tissues, tools, blood and smoke in the view. Our system has been evaluated on pre-clinical models and has shown to provide acceptable overlay accuracy even during extreme conditions.”

Augmented reality for surgery is an emerging trend, consisting of a computer-generated image for the operating surgeon to see. While using ultrasound during surgery allows the doctor to see the organ’s internal structures, when combined, the AR system significantly improves the surgeon’s comprehension of the ultrasound image in the context of the surgical view.

“The AR system that we developed will benefit patients because AR-guided surgeries can be more precise, safer and faster,” said Shekhar. “Through sustained research and development effort and robust clinical-technical partnership, Children’s National is leading in clinical translation and technology transfer of the laparoscopic AR visualization technology. Other solutions are more laboratory-based while our focus has been on building a clinically practical and viable solution from day one.”

Laparoscopic surgery is known to improve outcomes, cause less scarring and speed the recovery process since the surgeons create small incisions with the aid of a camera. Still, doctors have a limited view of anatomic structures and surgical targets below the exposed surfaces.

Given that AR is an emerging technology, this work would not have been possible until recently. According to the researchers, no other scientists in the field take advantage of both tracking hardware and computer vision-based approaches.

“This work is important because it features best of both worlds: relying on tracking hardware to ensure robustness while using computer vision to enhance accuracy. This will generate a more accurate and reliable AR system which is more feasible for clinical use,” said Shekhar.

The hybrid tracking mount for the LUS transducer

The hybrid tracking mount for the LUS transducer. The mount contains a six-DOF EM sensor and an AB with 21 markers fixed on three flat surfaces.

schematic of Mueller polarimetric imaging

Novel technique improved nerve visualization in head and neck surgery

In a pre-clinical model, researchers from Children’s National Hospital found that the Mueller polarimetric imaging, a novel technique that improves image contrast, may help identify nerves from other surrounding tissues during neck and head surgical procedures, avoiding accidental nerve damage.

“This technology holds great promise for the possibility of a truly noninvasive imaging approach and may help improve surgical outcomes by potentially reducing inadvertent, ill effects of nerve injuries in head and neck surgery,” said Bo Ning, Ph.D., R&D engineer at Children’s National and lead author of the study.

This pre-clinical study presents the first application of a full-field polarimetric imaging technique in vivo during head and neck surgery to highlight the vagus nerve (VN) and a branch that supplies all the intrinsic muscles to the larynx, known as recurrent laryngeal nerve (RLN).

“Unlike conventional nerve identification devices, this technique is noninvasive and less interruptive to intact tissues without disrupting surgical workflows,” said Ning et al. “Since the technique has an easy mechanism and promising performance in our study, this novel method holds great potential for real-time, noninvasive, and convenient nerve visualization.”

While some promising methods use polarimetric imaging for tissue characterizations, the current literature is still limited to ex vivo conditions due to the system complications and prolonged acquisition speeds.

“Recently, the industry released a new polarimetric camera, which is compact and allows fast and high-definition polarimetric imaging through simple snapshots. Enlightened by this technical advance, we have developed a practical polarimetric imaging method,” said Ning, who also develops compact and practical imaging systems for surgical innovation, including 3D, fluorescent, laser speckle and hyperspectral techniques. “It allows fast polarimetric analysis and can acquire birefringence maps over the whole field of view within 100 milliseconds, which provides an appropriate speed for directly surgical use.”

The new approach proofs that the concept is feasible to set up in live subjects during head and neck surgery, which can also be easily adapted for other surgeries. Among the seven subjects, the VNs and RLNs were successfully differentiated from arteries and other surrounding tissues.

Additional co-authors from Children’s National include Itai Katz, Ph.D., M.S., R&D staff engineer III; Anthony D. Sandler, M.D., Senior Vice President and Surgeon-in-Chief; Richard Jaepyeong Cha, Ph.D., research faculty assistant professor.

schematic of Mueller polarimetric imaging

Researchers at Children’s National used a novel technique that improves image contrast, which may help improve surgical outcomes.

Micrograph of human parasite Schistosoma mansonii

Diagnosing and monitoring of urogenital schistosomiasis

Micrograph of human parasite Schistosoma mansonii

Urogenital schistosomiasis (UGS) is caused by egg-laying S. haematobium worms dwelling within the veins draining the main pelvic organs, including the bladder, uterus, and cervix.

Although urogenital schistosomiasis remains a major global challenge, Michael Hsieh, M.D., Ph.D., director of Transitional Urology at Children’s National Hospital, and other experts including Eglal Shalaby Rana, M.D., from Children’s National, show in a new study published in Advances in Parasitology that newer refinements in associated technologies may lead to improvements in patient care.

In addition, application of investigational imaging methods, such as confocal laser endomicroscopy and two-photon microscopy in urogenital schistosomiasis, are likely to contribute to the understanding of this infection’s pathogenesis.

Read the full study in Advances in Parasitology.

Marius George Linguraru

$1M grant funds research on quantitative imaging for tumors

“For children who are at risk of losing their vision, this project will bring a window of opportunity for physicians to start treatment earlier and save their vision,” says Marius George Linguraru, DPhil, MA, MSc.

A team from Children’s National Hospital is part of a project receiving a two-year grant of nearly $1,000,000 from the National Institutes of Health (NIH) for the first pediatric project in the Quantitative Imaging Network (QIN) of the National Cancer Institute (NCI). Marius George Linguraru, DPhil, MA, MSc, principal investigator from the Sheikh Zayed Institute for Pediatric Surgical Innovation at Children’s National Hospital in Washington, D.C., is one of two principal investigators on the project, which focuses on developing quantitative imaging (QI) tools to improve pediatric tumor measurement, risk predictions and treatment response. Roger Packer, M.D., Senior Vice President of the Center for Neuroscience & Behavioral Health, Director of the Gilbert Neurofibromatosis Institute and Director of the Brain Tumor Institute, is co-investigator.

The project, in collaboration with Children’s Hospital of Philadelphia and Children’s Hospital Colorado, centers on the most common type of brain tumor in children, called a low-grade glioma. This project focuses on a clinically challenging group of children with neurofibromatosis type 1 (NF1), the most common inherited tumor predisposition syndrome. Nearly 20% of children with NF1 will develop a low-grade glioma called optic pathway glioma (OPG). In children with this type of brain tumor, the growth occurs around the optic nerve, chiasm and tracts, also called the optic pathway, which connects the eye to the brain. OPGs can cause vision loss and even blindness. Permanent vision loss usually occurs between one and eight years of age with doctors closely monitoring the tumor with magnetic resonance imaging (MRI) to assess the disease progression.

“Our traditional two-dimensional measures of tumor size are not appropriate to assess the changes in these amorphous tumors over time or how the tumor responds to treatment,” says Linguraru. “This means physicians have difficulty determining the size of the tumor as well as when treatment is working. Research such as this can lead to innovative medical technologies that can improve and possibly change the fate of children’s lives.”

Dr. Linguraru is leading the technical trials on this project, which take place in the first two years, or phase one, starting in June 2020. Phase one focuses on improving the often inaccurate human measurements of tumor size by developing QI tools to make precise and automated measures of tumor volume and shape using machine learning. In this phase, the project will use and homogenize MRI data from multiple centers to develop predictive models of the treatment response based on the tumor volume that are agnostic to the differences in imaging protocols. By doing this, it will allow physicians to make more informed decisions about the treatment’s success and whether the child will recover their vision.

When phase one is complete, Linguraru and the project’s other principal investigator Robert A. Avery, DO, MSCE, neuro-ophthalmologist in the Division of Ophthalmology at Children’s Hospital of Philadelphia, will initiate the second phase, which includes validating the QI application on data from the first ever phase III clinical trial comparing two treatments for NF1-OPGs. Phase two is scheduled to start in the Summer 2022 and continue through Summer 2025.

“For children who are at risk of losing their vision, this project will bring a window of opportunity for physicians to start treatment earlier and save their vision,” says Linguraru. “For those children who won’t benefit from chemotherapy because the tumor poses no threat to their sight, this project will save them from having to go through that difficult treatment unnecessarily. It will be life-changing for the children and their families, which is what excites me about this QI application.”

This project is a collaboration between Children’s Hospital of Philadelphia and Children’s National Hospital in Washington, D.C., in partnership with Children’s Hospital of Colorado and University of Pennsylvania. Upon project completion, the QI application will provide a precision-medicine approach for NF1-OPGs and improve clinical outcomes for pediatric tumors.

preterm baby

Validating a better way to stratify BPD risk in vulnerable newborns

preterm baby

Factoring in the total number of days that extremely preterm infants require supplemental oxygen and tracking this metric for weeks longer than usual improves clinicians’ ability to predict respiratory outcomes according to bronchopulmonary dysplasia severity.

Factoring in the total number of days that extremely preterm infants require supplemental oxygen and tracking this metric for weeks longer than usual improves clinicians’ ability to predict respiratory outcomes according to bronchopulmonary dysplasia (BPD) severity, a research team led by Children’s National Hospital writes in Scientific Reports. What’s more, the researchers defined a brand-new category (level IV) for newborns who receive supplemental oxygen more than 120 days as a reliable way to predict which infants are at the highest risk of returning to the hospital due to respiratory distress after discharge.

About 1 in 10 U.S. infants is born preterm, before 37 weeks gestation, according to the Centers for Disease Control and Prevention. That includes extremely preterm infants who weigh about 1 lb. at birth. These very low birthweight newborns have paper thin skin, frail hearts and lungs that are not yet mature enough to deliver oxygen throughout the body as needed. Thanks to advances in neocritical care, an increasing number of them survive prematurity, and many develop BPD, a chronic lung disease characterized by abnormal development of the lungs and pulmonary vasculature.

“About half of the babies born prematurely will come back to the hospital within the first year of life with a respiratory infection. The key is identifying them and, potentially, preventing complications in this high-risk population,” says Gustavo Nino, M.D., a Children’s National pulmonologist and the study’s lead author.

For decades, the most common way to stratify BPD risk in these vulnerable newborns has been to see if they require supplemental oxygen at 36 weeks corrected gestational age.

“The problem with this classification is it doesn’t take into account the very premature babies who are on oxygen for much longer than other babies. So, we asked the question: Can we continue risk stratification beyond 36 weeks in order to identify a subset of babies who are at much higher risk of complications,” Dr. Nino says.

The longitudinal cohort study enrolled 188 infants born extremely preterm who were admitted to the neonatal intensive care unit (NICU) at Children’s National and tracked their data for at least 12 months after discharge. The team used a multidimensional approach that tracked duration of supplemental oxygen during the newborns’ NICU stay as well as scoring lung imaging as an independent marker of BPD severity. To validate the findings, these U.S.-born newborns were matched with 130 infants who were born preterm and hospitalized at two NICUs located in Bogotá, Colombia.

“Babies who are born very preterm and require oxygen beyond 120 days should have expanded ventilation of the lungs and cardiovascular pulmonary system before going home,” he notes. “We need to identify these newborns and optimize their management before they are discharged.”

And, the babies with level IV BPD risk need a different type of evaluation because the complications they experience – including pulmonary hypertension – place them at the highest risk of developing sleep apnea and severe respiratory infection, especially during the first year of life.

“The earlier we identify them, the better their outcome is likely to be,” Dr. Nino says. “We really need to change the risk stratification so we don’t call them all ‘severe’ and treat them the same when there is a subset of newborns who clearly are at a much higher risk for experiencing respiratory complications after hospital discharge.”

In addition to Dr. Nino, Children’s National study co-authors include Awais Mansoor, Ph.D., staff scientist at the Sheikh Zayed Institute for Pediatric Surgical Innovation (SZI); Geovanny F. Perez, M.D., pediatric pulmonologist; Maria Arroyo, M.D., pulmonologist; Xilei Xu Chen, M.D., postdoctoral fellow; Jered Weinstock, pediatric pulmonary fellow; Kyle Salka, MS, research technician; Mariam Said, M.D., neonatologist, and Marius George Linguraru, DPhil, MA, MSc, SZI principal investigator and senior author. Additional co-authors include Ranniery Acuña-Cordero, Universidad Militar Nueva Granada, Bogotá, Colombia; and Monica P. Sossa-Briceño and Carlos E. Rodríguez-Martínez, both of Universidad Nacional de Colombia.

Funding for research described in this post was provided by the National Institutes of Health (NIH) under award Nos. HL145669, AI130502 and HL141237. In addition, the NIH has awarded Dr. Nino an RO1 grant to continue this research.

electronic cigarette dispenser with different flavors of nicotine

Extreme difficulty breathing and swallowing linked to teen’s vaping?

electronic cigarette dispenser with different flavors of nicotine

After a teen was transferred to Children’s National Hospital suffering from severe difficulty breathing and swallowing, a multidisciplinary team continued the detective work and surmises that vaping was to blame for her unusual symptoms.

A teenage girl with no hint of prior asthma or respiratory illness began to feel hoarseness in her throat and a feeling that she needed to clear her throat frequently. Within a few weeks, her hoarseness and throat-clearing worsened with early morning voice loss and feeling as if food were lodged in her throat. She started having trouble swallowing and began to avoid food all together.

Her pediatrician prescribed loratadine for suspected allergies to no avail. Days later, an urgent care center prescribed a three-day course of prednisone. For a few days, she felt a little better, but went back to feeling like she was breathing “through a straw.” After going to an emergency room with acute respiratory distress and severe difficulty swallowing, staff tried intravenous dexamethasone, ampicillin/sulbactam, and inhaled racemic epinephrine and arranged for transfer.

When she arrived at Children’s National Hospital, a multidisciplinary team continued the detective work with additional testing, imaging and bloodwork.

Examining her throat confirmed moderate swelling and a partially obstructed airway draped with thick chartreuse-colored mucus. The teen had no history of an autoimmune disorder, no international travel and no exposure to animals. She had no fever and had received all her scheduled immunizations.

“With epiglottitis – an inflammation of the flap found at the base of the tongue that prevents food from entering the trachea – our first concern is that an underlying infection is to blame,” says Michael Jason Bozzella, D.O., MS, a third-year infectious diseases fellow and lead author of the case report published Feb. 5, 2020, in Pediatrics. “We tested her specimens in a number of ways for a host of respiratory pathogens, including human rhino/enterovirus, respiratory syncytial virus, influenza, Epstein-Barr virus, Streptococcus and more. All negative. We also looked for more atypical infections with bacteria, like Arcanobacterium, Mycoplasma and Gonorrhea. Those were all negative as well,” Dr. Bozzella adds.

She slowly improved during a seven-day initial hospital stay, though soon returned for another six-day hospital stay after it again became excruciatingly painful for her to swallow.

Every throat culture and biopsy result showed no evidence of fungal, bacterial or viral infection, acid-fast bacilli or other malignancy. But in speaking with doctors, the teen had admitted to using candy-and fruit-flavored e-cigarettes three to five times with her friends over the two months preceding her symptoms. The last time she vaped was two weeks before her unusual symptoms began.

According to the Centers for Disease Control and Prevention, 2,668 people in the U.S. have been hospitalized for e-cigarette or vaping product use-associated lung injury, as of Jan. 14, 2020. The Children’s National case report’s authors say the increasing use of vaping products by teenagers highlights the potential for unknown health risks to continue to grow.

“This teenager’s use of e-cigarettes is the most plausible reason for this subacute epiglottitis diagnosis, a condition that can become life-threatening,” says Kathleen Ferrer, M.D., a hospitalist at Children’s National and the case report’s senior author. “This unusual case adds to a growing list of toxic effects attributable to vaping. While we normally investigate infectious triggers, like Streptococci, Staphylococci and Haemophilus, we and other health care providers should also consider e-cigarettes as we evaluate oro-respiratory complaints.”

In addition to Drs. Bozzella and Ferrer, Children’s National case report co-authors include Matthew Allen Magyar, M.D., a hospitalist; and Roberta L. DeBiasi, M.D., MS, chief of the Division of Pediatric Infectious Diseases.

sleeping baby

False negatives: Delayed Zika effects in babies who appeared normal at birth

sleeping baby

Colombian infants exposed to Zika virus in the womb showed neurodevelopmental delays as toddlers, despite having “normal” brain imaging and head circumference at birth, a finding that underscores the importance of long-term neurodevelopmental follow-up for Zika-exposed infants.

Colombian infants exposed to Zika virus in the womb showed neurodevelopmental delays as toddlers, despite having “normal” brain imaging and head circumference at birth, a finding that underscores the importance of long-term neurodevelopmental follow-up for Zika-exposed infants, according to a cohort study published online Jan. 6, 2020, in JAMA Pediatrics.

“These infants had no evidence of Zika deficits or microcephaly at birth. Neurodevelopmental deficits, including declines in mobility and social cognition, emerged in their first year of life even as their head circumference remained normal,” says Sarah B. Mulkey, M.D. Ph.D., a fetal/neonatal neurologist at Children’s National Hospital and the study’s first author. “About one-third of these newborns who underwent postnatal head ultrasound had nonspecific imaging results, which we believe are the first published results finding a link between subtle brain injuries and impaired neuromotor development in Zika-exposed children.”

The multi-institutional research group led by Children’s National enrolled pregnant women in Atlántico Department, which hugs the Caribbean coast of Colombia, who had been exposed to Zika, and performed a series of fetal magnetic resonance images (MRI) and ultrasounds as their pregnancies progressed.

Even though their mothers had laboratory-confirmed Zika infections, 77 out of 82 of their offspring were born with no sign of congenital Zika syndrome, a constellation of birth defects that includes severe brain abnormalities, eye problems and congenital contractures, and 70 underwent additional testing of neurodevelopment during infancy. These apparently normal newborns were born between Aug. 1, 2016, and Nov. 30, 2017, at the height of the Zika epidemic, and had normal head circumference.

When they were 4 to 8 months or 9 to 18 months of age, the infants’ neurodevelopment was evaluated using two validated tools, the Warner Initial Developmental Evaluation of Adaptive and Functional Skills (a 50-item test of such skills as self-care, mobility, communication and social cognition) and the Alberta Infant Motor Scale (a motor examination of infants in prone, supine, sitting and standing positions). Some infants were assessed during each time point.

Women participating in the study were highly motivated, with 91% following up with appointments, even if it meant traveling hours by bus. In addition to Children’s National faculty traveling to Colombia to train staff how to administer the screening instruments, videotaped assessments, MRIs and ultrasounds were read, analyzed and scored at Children’s National. According to the study team, the U.S. scoring of Alberta Infant Motor Scale tests administered in Colombia is also unprecedented for a research study and offers the potential of remote scoring of infants’ motor skill maturity in regions of the world where pediatric specialists, like child neurologists, are lacking.

“Normally, neurodevelopment in infants and toddlers continues for years, building a sturdy neural network that they later use to carry out complex neurologic and cognitive functions as children enter school,” Dr. Mulkey adds. “Our findings underscore the recommendations by the Centers for Disease Control and Prevention (CDC) that all infants exposed to Zika in the womb undergo long-term follow-up, providing an opportunity to intervene earlier.”

An accompanying editorial by CDC staffers concurs, saying the study reported “intriguing data” that add “to the growing evidence of the need for long-term follow-up for all children with Zika virus exposure in utero to ensure they receive the recommended clinical evaluations even when no structural defects are identified at birth.”

In addition to Dr. Mulkey, study co-authors include Margarita Arroyave-Wessel, MPH, Dorothy I. Bulas, M.D., chief of Diagnostic Imaging and Radiology, JiJi Jiang, MS, Stephanie Russo, BS, Robert McCarter, ScD, research section head, design and biostatistics,  Adré J. du Plessis, M.B.Ch.B., MPH, chief of the Division of Fetal and Transitional Medicine, and co-Senior Author, Roberta L. DeBiasi, MD, MS, chief of the Division of Pediatric Infectious Diseases, all of Children’s National; Colleen Peyton, PT, DPT, of Northwestern University; Yamil Fourzali, M.D., of Sabbag Radiologos, Barranquilla, Colombia; Michael E. Msall, M.D., of University of Chicago Comer Children’s Hospital; and co-Senior Author, Carlos Cure, M.D., BIOMELab, Barranquilla, Colombia.

Funding for the research described in this post was provided by the Thrasher Research Fund, the National Institutes of Health under award Nos. UL1TR001876 and KL2TR001877, and the Leadership Education in Neurodevelopmental and Related Disorders Training Program under grant HRSA/MCHB T73 MC11047.

brain network illustration

$2.5M to protect the brain from metabolic insult

brain network illustration

The brain comprises only 2% of the body’s volume, but it uses more than 20% of its energy, which makes this organ particularly vulnerable to changes in metabolism.

More than 30 million Americans have diabetes, with the vast majority having Type 2 disease. Characterized by insulin resistance and persistently high blood sugar levels, poorly controlled Type 2 diabetes has a host of well-recognized complications: compared with the general population, a greatly increased risk of kidney disease, vision loss, heart attacks and strokes and lower limb amputations.

But more recently, says Nathan A. Smith, MS, Ph.D., a principal investigator in Children’s National Research Institute’s Center for Neuroscience Research, another consequence has become increasingly apparent. With increasing insulin resistance comes cognitive damage, a factor that contributes significantly to dementia diagnoses as patients age.

The brain comprises only 2% of the body’s volume, but it uses more than 20% of its energy, Smith explains – which makes this organ particularly vulnerable to changes in metabolism. Type 2 diabetes and even prediabetic changes in glucose metabolism inflict damage upon this organ in mechanisms with dangerous synergy, he adds. Insulin resistance itself stresses brain cells, slowly depriving them of fuel. As blood sugar rises, it also increases inflammation and blocks nitric oxide, which together narrow the brain’s blood vessels while also increasing blood viscosity.

When the brain’s neurons slowly starve, they become increasingly inefficient at doing their job, eventually succumbing to this deprivation. These hits don’t just affect individual cells, Smith adds. They also affect connectivity that spans across the brain, neural networks that are a major focus of his research.

While it’s well established that Type 2 diabetes significantly boosts the risk of cognitive decline, Smith says, it’s been unclear whether this process might be halted or even reversed. It’s this question that forms the basis of a collaborative Frontiers grant, $2.5 million from the National Science Foundation split between his laboratory; the lead institution, Stony Brook University; and Massachusetts General Hospital/Harvard Medical School.

Smith and colleagues at the three institutions are testing whether changing the brain’s fuel source from glucose to ketones – byproducts from fat metabolism – could potentially save neurons and neural networks over time. Ketones already have shown promise for decades in treating some types of epilepsy, a disease that sometimes stems from an imbalance in neuronal excitation and inhibition. When some patients start on a ketogenic diet – an extreme version of a popular fat-based diet – many can significantly decrease or even stop their seizures, bringing their misfiring brain cells back to health.

Principal Investigator Smith and his laboratory at the Children’s National Research Institute are using experimental models to test whether ketones could protect the brain against the ravages of insulin resistance. They’re looking specifically at interneurons, the inhibitory cells of the brain and the most energy demanding. The team is using a technique known as patch clamping to determine how either insulin resistance or insulin resistance in the presence of ketones affect these cells’ ability to fire.

They’re also looking at how calcium ions migrate in and out of the cells’ membranes, a necessary prerequisite for neurons’ electrical activity. Finally, they’re evaluating whether these potential changes to the cells’ electrophysiological properties in turn change how different parts of the brain communicate with each other, potentially restructuring the networks that are vital to every action this organ performs.

Colleagues at Athinoula A. Martinos Center for Biomedical Imaging at Massachusetts General Hospital and Harvard Medical School, led by Principal Investigator Eva-Maria Ratai, Ph.D.,  will perform parallel work in human subjects. They will use imaging to determine how these two fuel types, glucose or ketones, affect how the brain uses energy and produces the communication molecules known as neurotransmitters. They’re also investigating how these factors might affect the stability of neural networks using techniques that investigate the performance of these networks both while study subjects are at rest and performing a task.

Finally, colleagues at the Laufer Center for Physical and Quantitative Biology at Stony Brook University, led by Principal Investigator Lilianne R. Mujica-Parodi, Ph.D., will use results generated at the other two institutions to construct computational models that can accurately predict how the brain will behave under metabolic stress: how it copes when deprived of fuel and whether it might be able to retain healthy function when its cells receive ketones instead of glucose.

Collectively, Smith says, these results could help retain brain function even under glucose restraints. (For this, the research team owes a special thanks to Mujica-Parodi, who assembled the group to answer this important question, thus underscoring the importance of team science, he adds.)

“By supplying an alternate fuel source, we may eventually be able to preserve the brain even in the face of insulin resistance,” Smith says.

kidneys with cysts on them

$6M gift powers new PKD clinical and research activities

kidneys with cysts on them

PKD is a genetic disorder characterized by clusters of fluid-filled sacs (cysts) multiplying and interfering with the kidneys’ ability to filter waste from the blood.

When Lisa M. Guay-Woodford, M.D., McGehee Joyce Professor of Pediatrics at Children’s National Hospital, considers a brand-new gift, she likens it to 6 million gallons of “rocket fuel” that will power new research to better understand polycystic kidney disease.

Dr. Guay-Woodford received a $5.7 million dollar gift to support PKD clinical and research activities. PKD is a genetic disorder characterized by clusters of fluid-filled sacs (cysts) multiplying and interfering with the kidneys’ ability to filter waste from the blood. The kidneys’ smooth surface transforms to a bumpy texture as the essential organs grow oversized and riddled with cysts.

The extraordinary generosity got its start in an ordinary clinical visit.

Dr. Guay-Woodford saw a young patient in her clinic at Children’s National a few times in 2015. The child’s diagnosis sparked a voyage of discovery for the patient’s extended family and, ultimately, they attended a presentation she gave during a regional meeting about PKD. That led to a telephone conversation and in-person meeting as they invited her to describe “the white space” between what was being done at the time to better understand PKD and what could be done.

“It’s the power of the art and science of medicine. They come to see people like me because of the science. If we can convey to patients and families that who they are and their unique concerns are really important to researchers, that becomes a powerful connection,” she says. “The art plus the science equals hope. That is what these families are looking for: We give people the latest insights about their disease because information is power.”

The infusion of new funding will strengthen the global initiative’s four pillars:

  • Coordinated care for children and families impacted by renal cystic disease. The Inherited and Polycystic Kidney Disease (IPKD) program, launched September 2019, includes a cadre of experts working together as a team in the medical home so that “in a single, one-stop visit, Children’s National can address the myriad concerns they have,” she explains. A multi-disciplinary team that includes nephrologists, hepatologists and endocrinology experts meets weekly to ensure the Center of Excellence provides the highest-caliber patient care. The team includes genetic counselors to empower families with knowledge about genetic risks and testing opportunities. A nurse helps families navigate the maze of who to call about which issue. Psychologists help to ease anxiety. “There is stress. There is fear. There is pain that can be associated with this set of diseases. The good news is we can control their medical issues. The bad news is some children have difficulty coping. Our psychologists help children cope so they can be a child and do the normal things that children do,” she says.
  • Strengthening global databases to capture PKD variations. The team will expand its outreach to other centers located around the world – including Australia, Europe, India and Latin America – caring for patients with both the recessive and dominant forms of polycystic kidney disease, to better understand the variety of ways the disease can manifest in children. “We really don’t know a lot about kids with the dominant form of the disease. How hard should we push to control their blood pressure, knowing that could ease symptoms? What are the ramifications of experiencing acute pain compared with chronic pain? How much do these pain flareups interfere with daily life and a child’s sense of self,” she asks. Capturing the nuances of the worldwide experience offers the power of harnessing even more data. And ensuring that teams collect data in a consistent way means each group would have the potential to extract the most useful information from database queries.
  • Filling a ‘desperate need’ for biomarkers. Developing clinical trials for new therapies requires having biomarkers that indicate the disease course. Such biomarkers have been instrumental in personalizing care for patients with other chronic conditions. “We are in desperate need for such biomarkers, and this new funding will underwrite pilot studies to identify and validate these disease markers. The first bite at the apple will leverage our imaging data to identify promising biomarkers,” she says.
  • Genetic mechanisms that trigger kidney disease. About 500,000 people in the U.S. have PKD. In many cases, children inherit a genetic mutation but, often, their genetic mutation develops spontaneously. Dr. Guay-Woodford’s research about the mechanisms that make certain inherited renal disorders lethal, such as autosomal recessive polycystic kidney disease, is recognized around the world. The fourth pillar of the new project provides funding to continue her lab’s research efforts to improve the mechanistic understanding of what triggers PKD.
Andrea Gropman

$5M in federal funding to help patients with urea cycle disorders

Andrea Gropman

Andrea L. Gropman, M.D.: We have collected many years of longitudinal clinical data, but with this new funding now we can answer questions about these diseases that are meaningful on a day-to-day basis for patients with urea cycle disorders.

An international research consortium co-led by Andrea L. Gropman, M.D., at Children’s National Hospital has received $5 million in federal funding as part of an overall effort to better understand rare diseases and accelerate potential treatments to patients.

Urea cycle disorder, one such rare disease, is a hiccup in a series of biochemical reactions that transform nitrogen into a non-toxic compound, urea. The six enzymes and two carrier/transport molecules that accomplish this essential task reside primarily in the liver and, to a lesser degree, in other organs.

The majority of patients have the recessive form of the disorder, meaning it has skipped a generation. These kids inherit one copy of an abnormal gene from each parent, while the parents themselves were not affected, says Dr. Gropman, chief of the Division of Neurodevelopmental Pediatrics and Neurogenetics at Children’s National. Another more common version of the disease is carried on the X chromosome and affects boys more seriously that girls, given that boys have only one X chromosome.

Regardless of the type of urea cycle disorder, when the urea cycle breaks down, nitrogen converts into toxic ammonia that builds up in the body (hyperammonemia), particularly in the brain. As a result, the person may feel lethargic; if the ammonia in the bloodstream reaches the brain in high concentrations, the person can experience seizures, behavior changes and lapse into a coma.

Improvements in clinical care and the advent of effective medicines have transformed this once deadly disease into a more manageable chronic ailment.

“It’s gratifying that patients diagnosed with urea cycle disorder now are surviving, growing up, becoming young adults and starting families themselves. Twenty to 30 years ago, this never would have seemed conceivable,” Dr. Gropman says. “We have collected many years of longitudinal clinical data, but with this new funding now we can answer questions about these diseases that are meaningful on a day-to-day basis for patients with urea cycle disorders.”

In early October 2019, the National Institutes of Health (NIH) awarded the Urea Cycle Disorders Consortium for which Dr. Gropman is co-principal investigator a five-year grant. This is the fourth time that the international Consortium of physicians, scientists, neuropsychologists, nurses, genetic counselors and researchers has received NIH funding to study this group of conditions.

Dr. Gropman says the current urea cycle research program builds on a sturdy foundation built by previous principal investigators Mendel Tuchman, M.D., and Mark Batshaw, M.D., also funded by the NIH. While previous rounds of NIH funding powered research about patients’ long-term survival prospects and cognitive dysfunction, this next phase of research will explore patients’ long-term health.

Among the topics they will study:

Long-term organ damage. Magnetic resonance elastrography (MRE) is a state-of-the-art imaging technique that combines the sharp images from MRI with a visual map that shows body tissue stiffness. The research team will use MRE to look for early changes in the liver – before patients show any symptoms – that could be associated with long-term health impacts. Their aim is spot the earliest signs of potential liver dysfunction in order to intervene before the patient develops liver fibrosis.

Academic achievement. The research team will examine gaps in academic achievement for patients who appear to be underperforming to determine what is triggering the discrepancy between their potential and actual scholastics. If they uncover issues such as learning difficulties or mental health concerns like anxiety, there are opportunities to intervene to boost academic achievement.

“And if we find many of the patients meet the criteria for depression or anxiety disorders, there are potential opportunities to intervene.  It’s tricky: We need to balance their existing medications with any new ones to ensure that we don’t increase their hyperammonemia risk,” Dr. Gropman explains.

Neurologic complications. The researchers will tap continuous, bedside electroencephalogram, which measures the brain’s electrical activity, to detect silent seizures and otherwise undetectable changes in the brain in an effort to stave off epilepsy, a brain disorder that causes seizures.

“This is really the first time we will examine babies’ brains,” she adds. “Our previous imaging studies looked at kids and adults who were 6 years and older. Now, we’re lowering that age range down to infants. By tracking such images over time, the field has described the trajectory of what normal brain development should look like. We can use that as a background and comparison point.”

In the future, newborns may be screened for urea cycle disorder shortly after birth. Because it is not possible to diagnose it in the womb in cases where there is no family history, the team aims to better counsel families contemplating pregnancy about their possible risks.

Research described in this post was underwritten by the NIH through its Rare Diseases Clinical Research Network.

zika virus

Neuroimaging essential for Zika cases

zika virus

About three years ago, Zika virus emerged as a newly recognized congenital infection, and a growing body of research indicates the damage it causes differs from other infections that occur in utero.

Seventy-one of 110 Brazilian infants at the highest risk for experiencing problems due to exposure to the Zika virus in the womb experienced a wide spectrum of brain abnormalities, including calcifications and malformations in cortical development, according to a study published July 31, 2019 in JAMA Network Open.

The infants were born at the height of Brazil’s Zika epidemic, a few months after the nation declared a national public health emergency. Already, many of the infants had been classified as having the severe form of congenital Zika syndrome, and many had microcephaly, fetal brain disruption sequence, arthrogryposis and abnormal neurologic exams at birth.

These 110 infants “represented a group of ZIKV-exposed infants who would be expected to have a high burden of neuroimaging abnormalities, which is a difference from other reported cohorts,” Sarah B. Mulkey, M.D., Ph.D., writes in an invited commentary published in JAMA Network Open that accompanies the Rio de Janeiro study. “Fortunately, many ZIKV-exposed infants do not have abnormal brain findings or a clinical phenotype associated with congenital Zika syndrome,” adds Dr. Mulkey, a fetal–neonatal neurologist in the Division of Fetal and Transitional Medicine at Children’s National in Washington, D.C.

Indeed, a retrospective cohort of 82 women exposed to Zika during their pregnancies led by a research team at Children’s National found only three pregnancies were complicated by severe fetal brain abnormalities. Compared with the 65% abnormal computed tomography (CT) or magnetic resonance imaging (MRI) findings in the new Brazilian study, about 1 in 10 (10%) of babies born to women living in the continental U.S. with confirmed Zika infections during pregnancy had Zika-associated birth defects, according to the Centers for Disease Control and Prevention.

“There appears to be a spectrum of brain imaging abnormalities in ZIKV-exposed infants, including mild, nonspecific changes seen at cranial US [ultrasound], such as lenticulostriate vasculopathy and germinolytic cysts, to more significant brain abnormalities, such as subcortical calcifications, ventriculomegaly and, in its most severe form, thin cortical mantle and fetal brain disruption sequence,” Dr. Mulkey writes.

About three years ago, Zika virus emerged as a newly recognized congenital infection, and a growing body of research indicates the damage it causes differs from other infections that occur in utero. Unlike congenital cytomegalovirus infection, cerebral calcifications associated with Zika are typically subcortical, Dr. Mulkey indicates. What’s more, fetal brain disruption sequence seen in Zika-exposed infants is unusual for other infections that can cause microcephaly.

“Centered on the findings of Pool, et al, and others, early neuroimaging remains one of the most valuable investigations of the Zika-exposed infant,” Dr. Mulkey writes, including infants who are not diagnosed with congenital Zika syndrome.  She recommends:

  • Cranial ultrasound as the first-line imaging option for infants, if available, combined with neurologic and ophthalmologic exams, and brainstem auditory evoked potentials
  • Zika-exposed infants with normal cranial ultrasounds do not need additional imaging unless they experience a developmental disturbance
  • Zika-exposed infants with abnormal cranial ultrasounds should undergo further neuroimaging with low-dose cranial CT or brain MRI.
Catherine Limperopoulos

Breastfeeding boosts metabolites important for brain growth

Catherine Limperopoulos

“Proton magnetic resonance spectroscopy, a non-invasive imaging technique that describes the chemical composition of specific brain structures, enables us to measure metabolites that may play a critical role for growth and explain what makes breastfeeding beneficial for newborns’ developing brains,” says Catherine Limperopoulos, Ph.D.

Micro-preemies who primarily consume breast milk have significantly higher levels of metabolites important for brain growth and development, according to sophisticated imaging conducted by an interdisciplinary research team at Children’s National.

“Our previous research established that vulnerable preterm infants who are fed breast milk early in life have improved brain growth and neurodevelopmental outcomes. It was unclear what makes breastfeeding so beneficial for newborns’ developing brains,” says Catherine Limperopoulos, Ph.D., director of MRI Research of the Developing Brain at Children’s National. “Proton magnetic resonance spectroscopy, a non-invasive imaging technique that describes the chemical composition of specific brain structures, enables us to measure metabolites essential for growth and answer that lingering question.”

According to the Centers for Disease Control and Prevention, about 1 in 10 U.S. infants is born preterm. The Children’s research team presented their findings during the Pediatric Academic Societies 2019 Annual Meeting.

The research-clinicians enrolled babies who were very low birthweight (less than 1,500 grams) and 32 weeks gestational age or younger at birth when they were admitted to Children’s neonatal intensive care unit in the first week of life. The team gathered data from the right frontal white matter and the cerebellum – a brain region that enables people to maintain balance and proper muscle coordination and that supports high-order cognitive functions.

Each chemical has its own a unique spectral fingerprint. The team generated light signatures for key metabolites and calculated the quantity of each metabolite. Of note:

  • Cerebral white matter spectra showed significantly greater levels of inositol (a molecule similar to glucose) for babies fed breast milk, compared with babies fed formula.
  • Cerebellar spectra had significantly greater creatine levels for breastfed babies compared with infants fed formula.
  • And the percentage of days infants were fed breast milk was associated with significantly greater levels of both creatine and choline, a water soluble nutrient.

“Key metabolite levels ramp up during the times babies’ brains experience exponential growth,” says Katherine M. Ottolini, the study’s lead author. “Creatine facilitates recycling of ATP, the cell’s energy currency. Seeing greater quantities of this metabolite denotes more rapid changes and higher cellular maturation. Choline is a marker of cell membrane turnover; when new cells are generated, we see choline levels rise.”

Already, Children’s National leverages an array of imaging options that describe normal brain growth, which makes it easier to spot when fetal or neonatal brain development goes awry, enabling earlier intervention and more effective treatment. “Proton magnetic resonance spectroscopy may serve as an important additional tool to advance our understanding of how breastfeeding boosts neurodevelopment for preterm infants,” Limperopoulos adds.

Pediatric Academic Societies 2019 Annual Meeting presentation

  • “Improved cerebral and cerebellar metabolism in breast milk-fed VLBW infants.”
    • Monday, April 29, 2019, 3:30–3:45 p.m. (EST)

Katherine M. Ottolini, lead author; Nickie Andescavage, M.D., Attending, Neonatal-Perinatal Medicine and co-author; Kushal Kapse, research and development staff engineer and co-author; Sudeepta Basu, M.D., neonatologist and co-author; and Catherine Limperopoulos, Ph.D., director of MRI Research of the Developing Brain and senior author, all of Children’s National.

Matthew Oetgen, M.D., discusses an image of a patient’s spine.

Eliminating unnecessary radiation exposure from spinal radiography

Matthew Oetgen, M.D., discusses an image of a patient’s spine.

Chief of Orthopaedics and Sports Medicine Matthew Oetgen, M.D., discusses an image of a patient’s spine.

If a child arrives at the pediatric orthopaedic specialist for an idiopathic scoliosis evaluation without an adequate radiographic image of his or her spine, it’s often necessary to order yet another imaging study for accurate assessment.

A study published in the Journal of the American Academy of Orthopaedic Surgeons found that in a 6 month period, almost half (43 percent) of patients referred for evaluation required a repeat radiograph due to missing or poor quality existing images.

“Repeating the radiograph means these kids received another exposure to radiation, too,” says Matthew Oetgen, M.D., the study’s lead author and chief of Orthopaedic Surgery and Sports Medicine at Children’s National Health System. “It’s frustrating because in many cases, a simple change in how the initial radiograph was taken could have prevented the need for more imaging studies.”

Dr. Oetgen and the study authors note that there is currently no standardized protocol for spinal radiography of suspected idiopathic scoliosis. However, a few basic criteria could greatly reduce the number of repeat images necessary. Radiographic images that allow for proper evaluation of idiopathic scoliosis and reduce radiation exposure include:

  • A full coronal view of the spine including skull base and pelvis
  • The iliac crest as an indicator of skeletal maturity
  • A full-length lateral view of the spine

Study authors also reinforced the need to do everything possible to reduce radiation exposure for children through proper use of protective shielding for reproductive organs and digital radiograph technology.

“Orthopaedic surgeons and pediatricians share the responsibility to ensure children are exposed to as little iatrogenic radiation as possible,” Dr. Oetgen concludes. “All physicians should be sure that the radiology facilities they refer patients to for spinal radiography employ every technology and safety measure available to limit radiation exposure. Additionally, we can and should work with radiologists to define evaluation criteria and improve what’s captured by radiography on the first try.”

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.

William Gaillard

Putting childhood epilepsy in the spotlight at American Epilepsy Society Meeting

William Gaillard

“We aim to build the evidence base for treatments that are effective specifically for children with epilepsy,” says William D. Gaillard, M.D., chief of Child Neurology, Epilepsy and Neurophysiology, and director of the Comprehensive Pediatric Epilepsy Program.

While epilepsy affects people of all ages, the unique way it manifests in infants, children and adolescents can be attributed in part to the complexities of the growing and developing brain. Researchers from the Children’s National Comprehensive Pediatric Epilepsy Program brought their expertise on the challenges of understanding and treating epilepsy in children to the recent American Epilepsy Society Annual Meeting, the largest professional gathering on epilepsy in the world.

“We aim to build the evidence base for treatments that are effective specifically for children with epilepsy,” says William D. Gaillard, M.D., chief of Child Neurology, Epilepsy and Neurophysiology, and director of the Comprehensive Pediatric Epilepsy Program. “We have learned much from studies in adult populations but technologies like functional MRI allow us to get in-depth understanding, often in non-invasive ways, of precisely how epilepsy is impacting a child.”

Dr. Gaillard was also recently elected to serve as the Second Vice President of the American Epilepsy Society. “The AES is the largest multidisciplinary professional and scientific society dedicated to the understanding, treatment and eradication of epilepsy and associated disorders, and I am honored to serve as the new Second Vice President,” he said.

The team’s presentations and poster sessions focused on several key areas in pediatric epilepsy:

Better ways to see, measure and quantify activity and changes in the brain for children with epilepsy before, during and after surgery

  • Novel applications of fMRI for children with epilepsy
    • Evaluation of an fMRI tool that tracks verbal and visual memory in children with epilepsy – one of the first to capture memory functions in this population of children using noninvasive fMRI;
    • Early study of the use of “resting-state” fMRI to map language skills before epilepsy surgery – an important first step toward noninvasively evaluating children who are too young or neurologically impaired to follow tasks in traditional MRI studies;
  • A study of whether intraoperative MRI, i.e. imaging during neurosurgery, allows for more complete removal of abnormal brain tissue associated with focal cortical dysplasia in children, which is a common cause of intractable epilepsy;
  • A preliminary case review of existing data to see if arterial spin labeling MRI, which measures blood flow to the brain, has potential to identify blood flow changes in specific locations of the brain where seizures occur;
  • An analysis of language laterality – the dominant side of the brain controlling language –  questioning the true reasons that the brains of children with epilepsy have differences in the hemisphere that predominantly controls language;
  • A review of some common assessments of language and working memory that are used pre- and post-operatively to gauge the impacts of pediatric epilepsy surgery. The study found that using multiple assessments, and studying results individually rather than as a group average, resulted in a more complete picture of the outcomes of surgery on these areas of brain function;
  • A preliminary study examining whether continuous EEG monitoring of neonates with hypoxic ischemic encephalopathy, or lack of oxygen to the brain, can be a reliable predictor of neurodevelopmental outcomes while the infant is undergoing therapeutic hypothermia.

“In order to expand our understanding of causes, impacts and outcomes, the range of research is broad given the complexity of epilepsy,” says Madison M. Berl, Ph.D. “This is the only way we can contribute to the goal of providing our colleagues and the families they serve with better resources to make informed decisions about how best to assess and treat pediatric epilepsy.”

The molecular, genetic and biological factors that contribute to onset and severity of pediatric epilepsy

  • A retrospective study of young patients with malformations in cortical development that are important causes of childhood epilepsy;
  • Investigation of a simple saliva test to effectively identify the presence of two common viral infections, human herpesvirus-6B and Epstein-Barr virus, that may be contributors to onset of epilepsy in otherwise normally functioning brains;
  • A preliminary review of the possible relationship between febrile infection-related epilepsy syndrome and the co-occurrence of another neuro-inflammatory condition – hemophagocytic lymphohistiocytosis.

Madison Berl, Ph.D., director of research in the Division of Pediatric Neuropsychology, and a pediatric neuropsychologist in the Comprehensive Pediatric Epilepsy Program, adds, “In order to expand our understanding of causes, impacts and outcomes, the range of research is broad given the complexity of epilepsy. This is the only way we can contribute to the goal of providing our colleagues and the families they serve with better resources to make informed decisions about how best to assess and treat pediatric epilepsy.”

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.

Elena Grant

Interventional cardiac magnetic resonance team welcomes new specialist

elena-grant-photo

The Interventional Cardiac Magnetic Resonance (ICMR) Program at Children’s National is actively developing newer and safer ways to perform cardiac procedures on young patients, with some of the world’s leading experts in cardiac catheterization and imaging. Elena Grant, M.D., a former pediatric cardiology fellow at Children’s National, is the newest member to join the team that pioneered real-time MRI-guided radiation-free cardiac catheterization for children.

In addition to clinical work as a Children’s National Interventional Cardiologist, Dr. Grant will perform preclinical research at the National Institutes of Health to develop new procedures, techniques, and devices that can be translated to clinical practice to treat children and adults with congenital heart disease.

Dr. Grant specializes in interventional cardiology. She received her medical degree from the University of Dundee Medical School in Dundee, Scotland, followed by Foundation Training in Edinburgh, Scotland. She completed her pediatric residency at Massachusetts General Hospital, her Pediatric Cardiology fellowship at Children’s National, and she recently finished an advanced fellowship in interventional pediatric cardiology at Children’s Healthcare of Atlanta and Emory University.

Advances in interventional cardiovascular MRI

Children’s National is at the forefront of this exciting new field and is currently the only institution in the United States to perform radiation-free MRI-guided cardiac catheterization procedures in children.

ICMR is a partnership with the National Institutes of Health that brings together researchers, clinicians, engineers, and physicists to provide radiation-free, less invasive, and more precise diagnostics and treatment options for pediatric patients and adults with congenital heart disease.

The ICMR approach to heart catheterization uses real-time MRI, instead of X-ray, in pediatric research subjects undergoing medically necessary heart catheterization. This research study is intended as a step toward routine MRI-guided catheterization in children, which attempts to avoid the hazards of ionizing radiation (X-ray).

In 2015, after working with NIH to explore how interventional cardiovascular MRI could be integrated into pediatric practices, the ICMR team, including Dr. Grant, Russell Cross, M.D., Joshua Kanter, M.D., and Laura Olivieri, M.D., performed the first  radiation-free MRI-guided right heart catheterization on a 14-year-old girl at Children’s National. Since then, nearly 50 such procedures have been successfully completed, and the team is working to broaden the age range and cardiac disease complexity of patients who can undergo the procedure.

About 1 percent of newborns are born with a heart condition, and the team at Children’s performs more than 450 X-ray guided cardiac catheterizations and over 500 cardiac MRI scans per year.