The developmental anatomy of congenital diaphragmatic hernia

Abstract

Uniform agreement on the mechanisms of closure of the pleuroperitoneal canals cannot be found in the literature. While many authors suggest that the pleuroperitoneal membrane has to join the transverse plate in order to close the canals, some suggest that the canal is “crowded out” by growth of the underlying organs. Scanning electron microscopic photographs presented in this paper show that closure happens in two layers: the internal canal is closed by liver and suprarenal gland and the external canal is closed at a membranous level. There is a striking difference in the shape of both canals. Up to now, the mechanisms of development of congenital diaphragmatic hernia are also unclear. We found six pathogenetic theories, most of these based on a “pressure” theory with subsequent secondary hypoplasia of the lung.