Only the most casual reference is made in literature to the deformities of the duodenum, and when the pyloric end of the stomach is the seat of intrinsic obstructive disorders the pylorus is almost invariably referred to as the seat of the obstructing cause.
In these later days of gastric surgery there is evident a growing sense of appreciation of the important rôle played by the duodenal ulcer in causing obstructive disorders of the stomach, and more critical analysis of the distribution of the so-called peptic ulcer tends to demonstrate an increasing ratio of duodenal ulcers. The tardy discovery of this fact is easily explained by the vaguely defined symptom-complex of the duodenal ulcer. During the last eight years I have operated on four cases of the so-called acute abdomen and discovered perforated duodenal ulcers.
In all these cases but one, the most careful canvass of the personal history failed
MACKENZIE KAJ. THE HOUR-GLASS DUODENUM.A PLEA FOR A MORE EXTENDED USE OF PLASTIC SURGERY TO PRESERVE THE DUODENAL ROUTE.. JAMA. 1906;XLVII(5):341-345. doi:10.1001/jama.1906.25210050025002e