Abstract: 【Objective】 To investigate the imaging features of struma ovarii (SO). 【Methods】 The pelvic CT or MRI images of 8 cases of struma ovarii were retrospectively analyzed. All cases were confirmed by pathology. 【Results】 8 cases of patients with pelvic CT or MR showed that the lesions were unilateral

of which 6 cases were left

2 cases in the right. All cases show cystic tumor or cystic tumor with solid components. For cystic lesion of four cases

one was unilocular

whereas three were multicystic. Another four cases were cystic tumor with solid components. In four of six cases with non-contrast CT images

high attenuation areas were recognized with the attenuation ranging from 45 to102 Hounsfield units (Hu). Solid components recognized as soft tissue mass were obviously enhanced on post-contrast CT images. In two cases with MR images

cystic components showed a variety of signal intensities. One showed low signal intensity on T1- weighted images and high signal intensity on T2-weighted images. Another showed slightly high signal intensity on T1-weighted images and variable signal intensities on T2-weighted images. The solid components showed isointense on T1-weighted images and isointense or slightly hyperintense on T2-weighted images. On post-contrast MR images

solid components were well enhanced. In one case

the cyst wall was moderately enhanced after administration of contrast medium. Ascites was present in two lesions. Calcifications were recognized in two lesions. 【Conclusion】 Struma ovarii presents with characteristic imaging features

and the key points focus on the density or signal characteristics of the cystic and solid components to be helpful in the diagnosis of this disease.