CT differentiation of large abdominal lymphangioma from ascites.

Abdominal lymphangiomas are uncommon benign tumors, usually presenting in early childhood as a palpable abdominal mass. Their sonographic and CT appearance has been well described, and usually consists of well-defined, thin-walled cysts which can be unilocular, or multiloculated, and may contain septations. Rarely, these cysts may be large enough to be confused with ascites on physical exam. We present such a case to emphasize the imaging features that may help in the differentiation between ascites and large mesenteric lymphangiomas.