A muscle spasm which closes the pylorus so that food cannot pass through into the duodenum.
Closure of the outlet of the stomach (pylorus) due to muscle spasm, leading to delay in the passage of stomach contents to the duodenum and vomiting. It is usually associated with duodenal or pyloric ulcers.
Spasm of the pyloric portion of the stomach. This interferes with the passage of food in a normal, gentle fashion into the intestine, causing the pain that comes on from half an hour to three hours after meals; it is associated with severe disorders of digestion. It is often produced by an ulcer of the stomach or duodenum.
Spasmodic contraction of the pyloric orifice. The usual cause is a disturbance in the motor innervation of the pyloric sphincter. It may occur secondary to lesions of the stomach or duodenum near the pyloric orifice. It may sometimes be mistaken for infantile hypertrophic pyloric stenosis.