OBJECTIVETo investigate the sonographic features of struma ovarii and its corresponding histopathologic findings.

METHODSThe sonographic and histopathological features of 72 patients with histopathologically comfirmed struma ovarii who were treated in Peking Union Medical College Hospital from January 2005 to December 2014 were retrospectively reviewed.

RESULTSOf these 72 patients,71 had benign struma ovarii(73 lesions)and one patient had malignant struma ovarii(1 lesion). On ultrasonography,all the 73 benign lesions had distinct margin,45(61.6%)had multilocular cystic or cystic-solid mass,49(67.1%)had irregular shape,and 28(38.4%)had nodular solid protrusions in the cystic areas. On the color Doppler flow imaging,36(49.3%)lesions had blood flow signals. The ultrasonographic features of the malignant struma ovarii lesion were multilocular cystic-solid mass with several nodular solid protrusions in the cysic areas;on the color Doppler flow imaging,blood flow signals were visible within septa and solid areas.

CONCLUSIONSThe sonographic features of struma ovarii are diverse. If ultrasonography reveals multilocular cystic or cystic-solid mass with distinct margin and isoechoic or hyperechoic nodular solid protrusions in the cystic areas with visible blood flow signals,the diagnosis of struma ovarii should be considered.