Patterns of misinterpretation of adnexal masses on CT and MR in an academic radiology department.

Rationale And Objectives: The aim of this study was to assess potential quality assurance (QA) issues in the diagnosis and characterization of adnexal masses on pelvic computed tomographic (CT) and magnetic resonance (MR) imaging studies.

Materials And Methods: Images from 128 women who had oophorectomies during a 16-month period with CT and/or MR studies within 5 years of surgery (145 CT scans from 103 women and 49 MR studies from 42 women, with 17 having both MR and CT studies) were reviewed by three radiologists who assigned QA scores of 0 (no QA issue), 1 (minor issue with minimal impact on clinical care), or 2 (major issue with potential impact on clinical care). The difficulty of diagnosis was assigned a score of 0 (very difficult diagnosis to make), 1 (difficult but possible to make the diagnosis), or 2 (diagnosis should be made). The incidence of adnexal QA issues was calculated using total CT and MR pelvic examinations performed on women during the interval.

Results: Twenty-nine QA issues were identified in 28 women in 17 of 145 CT studies (11.7%) and 12 of 49 MR examinations (24.5%) in women having adnexal surgery (17 of 11,194 [0.15%] of female pelvic CT studies and 12 of 603 [2.0%] of female pelvic MR studies performed in the time interval). Issues included missed lesions, lesions misidentified as leiomyomas, fat described in the lesion but not seen histologically, postmenopausal status of patient not considered, ultrasound correlation not recommended, and confusion of right and left sides.

Conclusion: Errors in CT and MR studies regarding the diagnosis and characterization of adnexal masses in a highly enriched population of women undergoing adnexal surgery are common. Knowledge of the types of QA issues found in CT and MR studies of adnexal masses should aid in decreasing future errors.