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Key Points
Defect in formation of diaphragm that is associated with pulmonary hypoplasia.
Incidence is around 1 in 2200 with 85% to 90% being left sided, 10% to 15% right sided, and 2% bilateral.
Approximately 60% of cases are isolated and 40% are complex or syndromic.
Multiple sonographic and MRI techniques have been described to predict lung volume, which is an important predictor of survival. Liver position is also very important with regard to outcome.
In the most severe cases of congenital diaphragmatic hernia (CDH), the fetal tracheal occlusion (FETO) with a balloon is removed prior to delivery “or EXIT-to-ECMO offers the best hope for survival.”
All fetuses with CDH should be delivered in a tertiary center with specific neonatal and surgical expertise in this condition and ECMO capability.
Cesarean section delivery is indicated only for standard obstetrical reasons.
Approximately a dozen single-gene disorders have CDH as a major feature. With increased cytogenetic resolution through array cGH, more syndromic cases are being recognized as being associated with a chromosome abnormality. Fetal karyotype is indicated.
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Congenital diaphragmatic hernia (CDH), a defect in the diaphragm, is thought to be due to failure of the pleuroperitoneal canal to close by 9 to 10 weeks of gestation and results in varying degrees of pulmonary hypoplasia from compression of the developing lungs by the herniated viscera (Harrison et al., 1993b). The traditional view that the diaphragm forms by fusion of the septum transversum, the esophageal mesentery, the pleuroperitoneal folds, and in growth of musculature from the lateral body wall, is now being questioned (Pober, 2008). In model organisms, recent work suggests that a nonmuscular diaphragmatic anlage first develops, and that the diaphragmatic musculature derives from muscle precursors that migrate through the pleuroperitoneal folds at approximately day 37 of gestation (Babiuk and Greer, 2002; Pober, 2008).
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During the development of the diaphragm, the peritoneal cavity is quite small and the midgut is normally present in the umbilical cord as physiologic herniation of the cord. If closure and muscularization of the pleuroperitoneal canal has not occurred by 9 or 10 weeks of gestation, when the midgut returns to the abdomen to undergo its normal 270-degree rotation, the viscera may herniate into the thorax through the posterolateral diaphragmatic defect because of limited intra-abdominal space (Areechon et al., 1963). If herniation occurs before the closure of the pleuroperitoneal canal there is no hernia sac. However, if pleuroperitoneal membrane has formed but is not muscularized, a hernia sac will be present and is observed in 10% to 15% of cases (Areechon et al., 1963). Occasionally, a “transient” herniation may occur later in gestation, with little effect on pulmonary development (Adzick et al., 1985a; Stringer et al., 1995).
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The clinical course of an infant with isolated CDH depends entirely on the degree ...