Echogenic forms of hydatid cysts: sonographic diagnosis.

Of 167 patients with abdominal hydatidosis, 29 showed a total of 36 hydatid cysts in which ultrasound demonstrated an overall echogenic appearance. The following ultrasound characteristics of an abdominal mass suggest the diagnosis of hydatid cyst: round or oval shape, well-defined borders, partial wall calcification, peripheral cystic structures, internal echogenic linear formations, snow storm and/or hyperechogenic internal echo pattern, and posterior acoustic enhancement. A comparative study with computed tomography has also been carried out in 10 of these cysts. Pathologic correlation in most cases allows us to postulate that this appearance represents an overly mature, probably ruptured, hydatid cyst.