Follow-up MRI recommendations for adnexal lesions on pelvic ultrasound: frequency, associations and outcomes

Purpose To assess the frequency and outcomes of follow-up MRI recommendations for adnexal lesions on pelvic US interpreted by US experts versus non-US expert abdominal radiologists.

In this IRB-approved, HIPAA-compliant retrospective cohort study, all pelvic US reports in adult women between 2018–2023 at a tertiary academic center were screened using a validated NLP algorithm for follow-up MRI recommendations for incidental adnexal lesions. MRI recommendation rates, compliance with the recommendation, and impact of MRI on management (malignancy risk upgrade/no change/downgrade and final outcomes) were compared between US expert and non-US expert abdominal radiologists.

Of 19,335 pelvic US in 14,328 patients (15,609, 80.7% read by US experts, 3726, 19.3% by non-US expert abdominal radiologists), 458 (2.3%) had follow-up MRI recommendations. US experts made fewer recommendations (248, 1.5% vs 210, 5.6%; p < 0.001) and had higher compliance rate (157, 63.3% vs 108, 51.4%; p = 0.01). MRI caused risk downgrade, no change, and upgrade in 191 (72.1%), 62 (23.4%), and 12 (4.5%) respectively; without significant difference between US experts and non-US experts (113, 72%, 39, 24.8%, 5, 3.2% vs 78, 72.2%, 23, 21.3%, 7, 6.5%; p = 0.96). Of 191 lesions with risk-downgrade, 124 underwent surgery (n = 60) or follow-up (n = 64) without any cancers; 67 had no further follow-up. Of 12 lesions with risk-upgrade on MRI, 6 (50%) were malignant, 4 (33.3%) benign, 2 (16.7%) borderline. Of 193 cases where MRI was not performed, 60 were resected (53, 88.3% benign, 3, 5.0% borderline, 4, 6.7% malignant).

US experts made fewer follow-up MRI recommendations, with no difference in the impact of MRI on risk-assessment between US experts and non-US expert radiologists. MRI resulted in malignancy risk-downgrade in most lesions and can potentially avoid unnecessary surgeries. Similar content being viewed by others Data availability No datasets were generated or analysed during the current study.

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J Am Coll Radiol 18:233–239. https://doi.org/10.1016/j.jacr.2020.02.021 Author information Authors and Affiliations Contributions SR and KSW wrote the main manuscript text. SR, KSW, and AS edited the manuscript text. SR, EN, and KSW prepared the figures and tables. All authors reviewed the manuscript. Corresponding author Ethics declarations Competing interests The authors declare no competing interests. Additional information Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. Rights and permissions Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. About this article Cite this article Rao, S., Najem, E., Shinagare, A. et al. Follow-up MRI recommendations for adnexal lesions on pelvic ultrasound: frequency, associations and outcomes. Abdom Radiol 51, 3115–3124 (2026). https://doi.org/10.1007/s00261-025-05289-w Received: Revised: Accepted: Published: Version of record: Issue date: DOI: https://doi.org/10.1007/s00261-025-05289-w