Giant cystic abdominal masses in children.

In this pictorial essay the common and uncommon causes of large cystic and cyst-like abdominal masses in children are reviewed. We discuss and illustrate the following: mesenchymal hamartoma, choledochal cyst, hydrops of the gallbladder, congenital splenic cyst, pancreatic pseudocyst, pancreatic cystadenoma, hydronephrosis, multicystic dysplastic kidney, multilocular cystic nephroma, adrenal hemorrhage, mesenteric and omental cysts, gastrointestinal duplication cyst, meconium pseudocyst, ovarian cysts and cystic neoplasms, hematocolpos, urachal cysts, appendiceal abscess, abdominal and sacrococcygeal teratoma, and CSF pseudocyst. We also describe imaging features and clues to the diagnosis.