Torsion of an ovarian cyst mimicking enteric duplication cyst on transabdominal ultrasound: two cases.

We describe two girls with abdominal cysts which demonstrated the "double wall" or "muscular rim" sign. On the basis of this, the diagnosis of duplication cyst was made in each case. At surgery, both were found to have ovarian cysts, and histology revealed prominent haemorrhage within the cyst wall. To our knowledge, there has been no previous report of a false-positive "double wall sign".