Prevention of reflux from the stomach into the oesophagus.

The normal mechanism of preventing the reflux of gastric contents into the oesophagus has been studied intensely, but no hypothesis is so easy to prove and understand that it has obtained universal acceptance (Allison, 1956; Barrett, 1954; Botha, Astley, and Carre, 1957; Marchand, 1955). Methods of prevention of reflux which has resulted in oesophageal pathology are therefore variable. Reflux is often shown by a barium meal to be associated with a hiatus hernia, and the presence of a length of oesophagus below the diaphragm acting as a flap valve has been thought to play some part in the normal mechanism for preventing reflux (Dornhorst, Harrison, and Pierce, 1954; Creamer, Harrison, and Pierce, 1959; Johnson, 1966). Most procedures designed to prevent reflux include securing a length of oesophagus below the diaphragm, but at the same time the diaphragm hiatus is tightened around the oesophagus and the oesophagus is made to enter the stomach at an acute angle. That reflux can occur without a hiatus hernia demonstrated by barium swallow has been accepted (Belsey, 1966). It is possible that a minimum length of oesophagus in the abdomen is required to prevent reflux and that when this is absent reflux can occur without a full-blown hernia being present. There is an area of thought and findings here which is not clear. A hernia may be demonstrated one day and not the next. With the hand in the abdomen and the chest open, the upper end of the stomach can be pushed into the chest through the hiatus. It is seen to move like a piston in a cylinder of surrounding tissue in the normal and abnormal. An operation is described which appears only to fix a length of oesophagus in the abdominal cavity. The results are described below. They indicate that a length of oesophagus in the abdominal cavity acts as a valve on its own merits under these conditions, without an acute angle of entry into the stomach and without narrowing of the hiatus.