Struma ovarii simulating a teratodermoid cyst. Computed tomographic findings in one case

A case report is presented in which there were computed tomographic (CT) findings of struma ovarii (SO) simulating a teratodermoid cyst. The patient was a 73-year-old woman with a painful mass in the lower abdomen. CT revealed a large complex mass with multiple cystic and solid components. One of the cysts had fat-fluid level and minor calcification in the wall. The histological findings were struma ovarii. To our knowledge, these CT findings have not been described previously. Our case demonstrates the importance of including struma ovarii in the CT differential diagnosis of teratodermoid cysts.