Fetal liver and lung volume index of neonatal survival with congenital diaphragmatic hernia

Background: Magnetic resonance imaging (MRI) assesses pulmonary hypoplasia in fetal congenital diaphragmatic hernia (CDH). Neonatal mortality may occur with CDH. Objective: To quantify MRI parameters associated with neonatal survival in fetuses with isolated CDH. Materials and methods: Fetal MRI for assessing CDH included region of interest (ROI) measurements for total lung volume (TLV), herniated liver volume, herniated other organ volume and predicted lung volume. Ratios of observed lung volume and liver up volume to predicted lung volume (observed to predicted TLV, percentage of the thorax occupied by liver) were calculated and compared to neonatal outcomes. Analyses included Wilcoxon rank sum test, multivariate logistic regression and receiver operating characteristic (ROC) curves. Results: Of 61 studies, the median observed to predicted TLV was 0.25 in survivors and 0.16 in non-survivors (P=0.001) with CDH. The median percentage of the thorax occupied by liver was 0.02 in survivors and 0.22 in non-survivors (P<0.001). The association of observed to predicted TLV and percentage of the thorax occupied by liver with survival for gestational age (GA) >28 weeks was greater compared to GA ≤28 weeks. The ROC analysis demonstrated an area under the curve of 0.96 (95% confidence interval 0.91–1.00) for the combined observed to predicted TLV, percentage of the thorax occupied by liver and GA. Conclusion: The percentage of the thorax occupied by liver and observed to predicted TLV was predictive of neonatal survival in fetuses with CDH.