Pyloric stenosis is a condition in young infants where the muscle at the outlet of the stomach (pylorus) thickens and blocks food from passing into the small intestine.
Forceful, projectile vomiting after feeds (often a few weeks after birth), persistent hunger, dehydration, and weight loss or poor weight gain.
Imaging confirms the thickened pyloric muscle and measures the length and thickness — both used to make the diagnosis.
Abdominal ultrasound is the test of choice; it directly measures pyloric muscle thickness and channel length.
Treatment is a small operation called pyloromyotomy after correcting any fluid and electrolyte imbalance; recovery is usually quick.
This entry explains the condition. The next step is having a radiologist interpret your specific scan, not a general definition.