[Sonographic appearances of mesenteric cysts--report of 2 cases].

Mesenteric cyst is defined as a cystic mass located in the mesentery, and has rarely been reported. Before the clinical use of ultrasound (US), the imaging diagnosis of the abdominal mass depended on plain X-ray films and contrast examinations to delineate the space occupying lesion. The later use of US enables us to readily identify mass character. For example, whether it is cystic or solid, with or without septum, or whether there is sediment in the cyst. US examination is the method of choice in evaluating abdominal masses. Two cases of pediatric mesenteric cysts were brought to our hospital on account of complication. US of the first patient revealed a huge cystic mass with sediment and septae in central abdomen. Mild hydronephrotic change of the right kidney was found. The pathology showed nonepithelial lining multiloculated cyst surrounded by a thick, fibrotic granulomatous wall with suppurative cell infiltration and some calcifications. The histopathological diagnosis was an infected pseudocyst. The other patient had a cyst which twisted the jejunum and resulted in intestinal obstruction. US found dilated intestinal loops and a septate cystic mass in epigastrium. The pathology showed a multiloculated cyst with mesothelial lining, representing a mesothelial cyst. Both patients were treated surgically and had an uneventful recovery. In this article we described and explained the findings on US, discussed the differential diagnoses and compared different imaging modalities.