Imaging description

Antenatal screening ultrasound (US) demonstrated multiple echogenic rounded foci within the left chest causing mass effect on the heart. The stomach was not noted to be in its expected location within the left upper abdomen. Longitudinal US images demonstrated the stomach above the diaphragm and the heart shifted towards the right side of the chest (Fig. 80.1a, b). T2-weighted MR sequences demonstrated multiple rounded hyperintense (fluid-filled) bowel loops in the left chest and the heart shifted towards the right aspect of the chest (Fig. 80.1c–e). The diagnosis of left congenital diaphragmatic hernia (CDH) was suggested. Immediate postnatal chest radiograph in a different patient with CDH demonstrated both opacification of the left hemithorax and multiple rounded lucencies in the left thorax, representing a combination of herniated tissues and gaseous distended bowel loops (Fig. 80.2).

Importance

CDH affects 1/3000 live births. The diaphragm is completely formed at eight weeks of gestation by the septum transversum and the pleuroperitoneal membranes. A defect in formation of the diaphragm leads to CDH. Approximately 85–90% of diaphragmatic hernias occur on the posterolateral left side, referred to as a Bochladek hernia, 5% occur in the anteromedial region, referred to as a Morgagni hernia. Morgagni hernias are frequently small and asymptomatic and discovered incidentally postnatally. The following discussion refers to the Bochdalek hernia as CDH. Despite advances in antenatal and perinatal care, when CDH is associated with morphologic or genetic anomalies, there is a high overall mortality rate of up to 50%. Severe pulmonary hypoplasia and pulmonary hypertension are the main etiologies for one-third of neonatal deaths from CDH. The administration of antenatal steroids, use of extracorporeal membrane oxygenation (ECMO), new modes of ventilation, timing of the hernia repair, as well as ex utero intrapartum treatment (EXIT) to ECMO along with intermittent in utero fetal tracheal occlusion have provided neonatologists and surgeons with various modes of management.