Enteric duplication cysts are rare lesions, and relatively few cases h
ave been diagnosed prenatally. We report two cases with a distinctive
presentation One, a duplication of the antrum of the stomach, was adja
cent to an extralobar pulmonary sequestration. The other, a duodenal d
uplication, appeared as a thick-walled right lower quadrant cyst. We o
bserved distinct peristalsis in this cyst, a finding that helped us ma
ke a firm diagnosis of enteric duplication.