Hypertrophic Pyloric Stenosis

  • Etiology: hypertrophy of pylorus muscle
  • AXR: caterpillar sign due to hyperperistalsis
  • US: pyloric muscle > 3.5 mm thick, pyloric channel > 17 mm long
  • UGI: antrum + duodenal bulb deformity on upper GI: antral shouldering + pyloric beak / teat + tram track through pylorus
  • DDX: prostaglandin E induced gastritis

Cases of Hypertrophic Pyloric Stenosis