Presentation
Projectile vomiting.
Patient Data

Enlarged pylorus. The length was 16 mm (upper limit of normal 14 mm), and the muscle thickness was 4 mm (upper limit of normal 3 mm).
This image also shows the “antral nipple sign” - redundant pyloric mucosa protruding into the gastric antrum, and the “cervix sign” - indentation of the pylorus into the fluid-filled antrum. The most telling sign, however, was that no gastric contents were seen to pass through the pylorus at any time during the examination.
Case Discussion
Pyloric stenosis affects males 4-5 times more often than females. It occurs between 4-8 weeks of life, and presents with non-bilious projectile vomiting. There may be a positive family history.
Ultrasound findings include:
- target sign: hypertrophied hypoechoic muscle surrounding echogenic mucosa
- elongated pylorus with thickened muscle
- cervix sign
- antral nipple sign
- exaggerated peristalsis
- failure of the pylorus to open