Prenatal MRI evaluation of congenital diaphragmatic hernia

The objective of this paper is to evaluate the efficacy of various magnetic resonance imaging (MRI) sequences and the general usefulness of prenatal M RI in determining the position of the fetal liver and visualizing lung tiss ue in fetuses who have congenital diaphragmatic hernia (CDH). This was a re trospective review of prenatal MRI of fetuses with a confirmed diagnosis by surgery or autopsy of CDH. MRI was per formed in a 1.5-Tesla magnet using fast gradient echo, half-fourier single-shot turbo spin-echo (HASTE) and ec ho 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 w ith 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 bila teral CDH (1) and agreed with the postnatal diagnosis in all patients. Ultr asound (US) diagnosed left CDH (33), right CDH (2), and congenital cystic a denomatoid malformation (3). MRI changed the diagnosis in four patients. Th e fetal liver war easily demonstrated with MRI in all fetuses and was herni ated into the chest in 25 of the 38. US diagnosed liver up in 21. Correlati on with postnatal studies found MRI correctly diagnosed liver position in 3 7 out of 38 cases. US correctly diagnosed liver position in 32 out of 38. B oth lungs could be visualized in all fetuses with MRI. MRI accurately and e asily diagnoses CDH and can differentiate it from other chest masses, MRI w as superior to US in demonstrating the position of the fetal liver above or below the diaphragm. MRI reliably visualized fetal lung tissue. These find ings are important for counseling parents, selecting fetal surgical candida tes, and estimating prognosis.