[Echographic diagnosis of hypertrophic stenosis of the pylorus].

We reviewed the abdominal sonograms of thirty three infants presenting with vomiting. Thirty patients were clinically suspected of having hypertrophic pyloric stenosis. The thickened pyloric muscle was seen as a hypoechoic mass with strong central echoes, situated medial to the gallbladder, and anterior to the right kidney and caval vein, in transverse and longitudinal sections respectively. The muscle thickness measured between 3.8 and 7 mm. These findings were found in thirty infants, in 27 of whom the diagnosis was clinically suspected, and the other three were presumed to have gastroesophageal reflux. All of them had subsequent confirmation of hypertrophic pyloric stenosis by upper gastrointestinal tract examination and/or surgery. Real time ultrasound is considered a useful, quick, reliable and non invasive method to confirm the hypertrophic pyloric stenosis in infants with vomiting.