ABSTRACT
-The objective of this paper is to evaluate the efficacy of various magnetic resonance
imaging (MRI) sequences and the general usefulness of prenatal MRI in determining
the position of the fetal liver and visualizing lung tissue in fetuses who have congenital
diaphragmatic hernia (CDH). This was a retrospective review of prenatal MRI of fetuses
with a confirmed diagnosis by surgery or autopsy of CDH. MRI was performed in a 1.5-Tesla
magnet using fast gradient echo, half-Fourier single-shot turbo spin-echo (HASTE)
and echo planar images. The presence of a chest mass, position of the stomach and
liver and visualization of the lungs by MRI was noted in all fetuses. This was compared
to ultrasound studies performed the same day and correlated with postnatal or autopsy
studies. The fetuses were 18-36 weeks gestational age (mean 24.5 weeks). MRI diagnosed
left CDH (33), right CDH (4), and bilateral CDH (1) and agreed with the postnatal
diagnosis in all patients. Ultrasound (US) diagnosed left CDH (33), right CDH (2),
and congenital cystic adenomatoid malformation (3). MRI changed the diagnosis in four
patients. The fetal liver was easily demonstrated with MRI in all fetuses and was
herniated into the chest in 25 of the 38. US diagnosed liver up in 21. Correlation
with postnatal studies found MRI correctly diagnosed liver position in 37 out of 38
cases. US correctly diagnosed liver position in 32 out of 38. Both lungs could be
visualized in all fetuses with MRI. MRI accurately and easily diagnoses CDH and can
differentiate it from other chest masses. MRI was superior to US in demonstrating
the position of the fetal liver above or below the diaphragm. MRI reliably visualized
fetal lung tissue. These findings are important for counseling parents, selecting
fetal surgical candidates, and estimating prognosis.
KEYWORD
Prenatal diagnosis - congenital diaphragmatic hernia - MRI
