At the Center for Fetal Diagnosis and Treatment, we believe one of the most important elements of care is careful diagnostic testing and interpretation of results.
At their first visit with us, women undergo a day of testing using the most advanced diagnostic equipment to determine the position of the liver, the lung volumes and the lung-to-head circumference ratio (LHR) in order to better predict the severity of the congenital diaphragmatic hernia (CDH), a baby’s chances of survival and whether they’ll need respiratory support at birth.
A sonographer and radiologist, both highly specialized in diagnosing fetal anomalies, use state-of-the-art ultrasound machines and high frequency probes, as well as 3-D and 4-D techniques if needed, to visualize a baby’s condition. The examination is held in a private room with a television screen overhead so the family can watch the ultrasound in real time. Our team is thorough, examining the liver, lung, face, fingers and toes. We have developed specific ultrasound protocols for each suspected anomaly and typically devote up to 1 1/2 hours for each initial scan. The team’s expertise frequently leads to additional findings that help with a baby’s treatment.
CDH protocol includes:
- 2-D and 3-D views of the diaphragm to show the site, size and contents of the defect.
- Gallbladder imaging (often appears displaced across the midline in left CDH or herniated into the thorax in right CDH cases).
- Color Doppler to illustrate the course of the superior mesenteric artery and the hepatic veins.
- CINE clips to demonstrate bowel peristalsis, as the texture of herniated small bowel loops can occasionally appear similar to the lung echo-texture.
- The highest frequency transducer possible (typically 9 MHz) to show the most detailed resolution.
- Estimation of the volume of the ipsilateral spared lung and the contralateral compressed lung.
- Classification of the degree of mediastinal shift as mild, moderate or severe, with mild representing displacement of the heart just past the midline and severe representing heart displacement to the contralateral chest wall.
“We spend a significant amount of time determining the exact contents that are herniated, taking special views that people don’t usually take, and using color Doppler in a way that’s not usually done,” says Beverly G. Coleman, MD, FACR, director of Fetal Imaging, Center for Fetal Diagnosis and Treatment. Dr. Coleman, a full professor, has been dedicated to imaging fetal anomaly cases at CHOP for more than 15 years.
Fetal magnetic resonance imaging (MRI) supplements the information obtained by ultrasound, often providing higher quality images that make it easier to differentiate between liver and lung, measure lung volume, and rule out any neurologic abnormalities. A core group of technologists perform fetal MRI daily and try to make the experience as comfortable as possible for patients. CHOP pioneered the first ultrafast fetal MRI in the United States. We also pioneered 3 Tesla fetal imaging in the U.S., which we utilize to improve signal to noise ratio, allowing for a much better image and detail of the fetus. This imaging coupled with ultrafast techniques results in shorter scan times and increased visualization of anatomy.
“This level of imaging and planning is not done at all centers,” says Teresa Victoria, MD, PhD, Center for Fetal Diagnosis and Treatment radiologist. “But here it’s a standard of care.”
(L) Coronal image of the diaphragm, (R) Transverse image of stomach, posterior to heart and lateral to BPS
Complex referred cases made clear by our imaging team
- Bowel only CDH with a normal stomach in the left upper quadrant
- CDH misconstrued as congenital pulmonary airway malformation (CPAM) due to fluid in herniated bowel loops or right diaphragmatic defects with a herniated gallbladder
- Diaphragmatic eventration thought to represent CDH
- CDH with associated subtle anomalies including ipsilateral bronchopulmonary sequestration
- Bilateral CDH which may completely lack evidence of mediastinal shift
- Various syndromes, e.g., Fryns and Pallister-Killian, among others
By the numbers
Milestones in CDH Care at CHOP
- 1991 ECMO Program founded
- 1995 CFDT opens
- 2004 Neonatal Surgical Team founded
- 2004 Pulmonary Hypoplasia Program launched
- 2008 SDU opens
CFDT Experience with CDH — 1995–2012
- 909 Patient referrals
- 581 Patients evaluated
- 115 Babies with CDH delivered in the SDU since July 2008
- 288 Patients with CDH repaired postnatally
- 133 CDH patients on ECMO