Stenosis due to duodenal ulceration.

THE lumen of the first part of the duodenum is a comparatively narrow segment of the alimentary canal so that when the surgeon passes his finger along its length at operation he finds that its mucosa hugs him comfortably. Placing an ulcer into this canal and surrounding its crater by scar tissue would, one might think, produce stenosis in a high percentage of cases, yet the somewhat surprising fact is that obstruction due to duodenal ulceration is comparatively uncommon. When stenosis does occur, it is rarely produced simply by fibrous scar tissue. Usually obstruction occurs in the presence of active ulceration and a considerable part of the obstructive factor is produced by associated inflammatory oedema and pylorospasm. Indeed, if the ulcer heals under intensive medical treatment. the clinical features of the stenosis regress and there may even be long term relief of the obstructive symptoms (Brown, 1959).