Posts

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 epilepsym,” 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.