Introduction
Congenital diaphragmatic hernia (CDH) is a severe birth defect, occuring in approximately 1 in 3,000 live born neonates. 1Despite optimal neonatal treatment, the disease is associated with high mortality and survivors often suffer short and long term morbidities.1 These include respiratory, gastro-intestinal and neurologic impairments.2Neurodevelopmental delays, as well as behavioral difficulties have been linked to CDH in the past and certain risk factors have been suggested, including gestational age at birth, disease severity, associated anomalies, the requirement for extracorporeal membrane oxygenation and long stay in the neonatal intensive care unit. 2-5
In infants with CDH, imaging studies have demonstrated several abnormalities including increased extra-axial space, delayed sulcation and white matter injury but the exact mechanisms remain unclear. As for other congenital malformations with an increased risk for neurodevelopmental abnormalities, parents may ask whether these are already present at the time of prenatal diagnosis, or they are more likely to be postnatally acquired. This will become even more important with the advent of effective fetal therapy 6, 7, which aims at fetuses with the more severe forms of CDH. For those parents and physicians likewise will want to understand whether brain development in CDH is already altered prenatally, and when present, if this would be severity dependent.8 Currently, there is limited data on in utero brain development in CDH fetuses. 8-10. Radhakrishnan et al described enlargement of the extra-axial space and congestion of the venous sinuses in the third trimester. A further study reported a correlation between cerebellar and vermian dimensions and the severity of lung hypoplasia (evidenced by a lower fetal lung volume).8 Recently, we described in a longitudinal ; study changes in cerebellar growth, and correlated this to disease severity; this study however was done by ultrasound.5
The objective was to describe brain development in CDH fetuses however using the gold standard imaging modality (MRI) to document cortical folding as well as the dimensions and volume of different brain structures in comparison to that in normal fetuses longitudinally during the second half of pregnancy.