The Blood Supply of the Oesophagus in Relation to Oesophageal Atresia.

Over 100 years ago vascular insufficiency was suggested as a cause of intestinal atresia. This remained a popular hypothesis until Tandler (1902) produced his work on the development of the duodenum, showing a stage at which the lumen was obliterated and postulating that arrest of development at this stage and failure of recanalization produced atresia. This theory was applied indiscriminately to all parts of the gut and continues to be quoted as a cause of oesophageal atresia, although Johns (1952) demonstrated that in human development the oesophagus was never completely occluded. It is partly because of a lack of knowledge of normal development that the pathogenesis of congenital abnormalities, particularly those of the alimentary tract, is not fully understood. Two facts, however, must be accepted. First, most congenital defects can be produced by any one of several agents acting during a certain period of embryonic development, and a specific agent may produce different anomalies when applied at different stages of development. Secondly, the normal development of the embryo must depend on an adequate oxygen supply and nutrition; and after the foetal heart begins to beat in the fourth week (4 mm. stage) the development of the various organs must depend on the development of their blood vessels and the maintenance of a normal blood supply through those vessels. Louw (1959) showed experimentally that various small bowel atresias could be produced by surgical interference with the blood supply to the gut of puppies in utero. In oesophageal atresia Keith and Spicer in 1906 found anomalous aortic arches and anomalous right subclavian arteries, and Fluss and Poppen (1951) more recently suggested that anomalies in arteries and fourth aortic arch remnants might be more common than was appreciated. The suggestion of these authors was that oesophageal atresia could be produced by pressure from abnormal vessels. A careful dissection of the post-mortem material of 15 cases of oesophageal atresia at the Queen Elizabeth Hospital for Children in London revealed