Gastric outlet obstruction: unusual ultrasonographic findings in the pyloric and antral regions.

: The authors present the cases of four infants aged 2-4 months with symptoms suggesting gastric outlet obstruction. All four had US evaluation of the antropyloric region and upper GI series. Three of them underwent endoscopic investigations and three, surgery. US demonstrated hypertrophied pyloric muscle and, above all, antropyloric abnormalities in all cases, namely a solid mass within the pyloric canal, hypertrophy of the pyloric mucosa in two cases and a double juxtapyloric cyst with an ulcer. Differential diagnosis of the sonographic images is discussed in each case.