"Sea urchin sign": a radiological indicator of fibrotic deep infiltrating endometriosis

Data availability No datasets were generated or analysed during the current study. References VanBuren W, Feldman M, Shenoy-Bhangle AS et al (2024) Radiology State-of-the-art Review: Endometriosis Imaging Interpretation and Reporting. Radiology 312 3:e233482 https://doi.org/10.1148/radiol.233482 Jha P, Sakala M, Chamie LP, et al (2020) Endometriosis MRI lexicon: consensus statement from the society of abdominal radiology endometriosis disease-focused panel. Abdom Radiol 45:1552–1568. https://doi.org/10.1007/s00261-019-02291-x Mason BR, Chatterjee D, Menias CO, Thaker PH, Siegel CL, Yano M (2020) Encyclopedia of endometriosis: a pictorial rad-path review. Abdom Radiol 45:1587–1607. https://doi.org/10.1007/s00261-019-02381-w Takeuchi M, Matsuzaki K, Harada M (2024) Endometriosis, a common but enigmatic disease with many faces: current concept of pathophysiology, and diagnostic strategy. Jpn J Radiol 42:801–819. https://doi.org/10.1007/s11604-024-01569-5 Testini V, Eusebi L, Grechi G, Bartelli F, Guglielmi G (2022) Imaging of Endometriosis: The Role of Ultrasound and Magnetic Resonance. Curr Radiol Rep 10:21–39. https://doi.org/10.1007/s40134-022-00393-x Varela C, Zulfiqar M, Schiappacasse G, Menias CO (2021) ‘Fortune cookie sign’: a variant of mushroom cap sign on T2 weighted MRI for deep sigmoid endometriosis. Abdom Radiol 46:1272–1275. https://doi.org/10.1007/s00261-020-02735-9 Giannini A, Pisaneschi S, Malacarne E, Cela V, Melfi F, Perutelli A, Simoncini T (2018) Robotic Approach to Ureteral Endometriosis: Surgical Features and Perioperative Outcomes. Front Surg. 5:51. https://doi.org/10.3389/fsurg.2018.00051. Piozzi GN, Burea V, Duhoky R, Stefan S, So C, Wilby D, Tsepov D, Khan JS (2024) Robotic surgery for bowel endometriosis: a multidisciplinary management of a complex entity. Tech Coloproctol. 28 1:31. https://doi.org/10.1007/s10151-023-02904-0 Colak C, Chamie LP, Youngner J, Forney MC, Luna Russo MA, Gubbels A, VanBuren WM, Feldman M (2024) MRI Features of Pelvic Nerve Involvement in Endometriosis. Radiographics. 44 1:e230106. https://doi.org/10.1148/rg.230106. Author information Authors and Affiliations Contributions N.W. and M.Y. wrote the main manuscript text. N.W. prepared the figures. M.S. provided photograph of the sea urchin in water. All authors reviewed the manuscript. Corresponding author Ethics declarations Conflict of interest Dr. VanBuren is Course Director and Founder of the International Endometriosis Imaging Congress for which she receives no profit. Funding received for travel to lecture at numerous Radiology and Gynecology societies and for non-profit organizations such as SWHR (Society for Women's Health Research) to support advocacy initiatives on Capitol Hill. Additional information Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. Rights and permissions About this article Cite this article Warrington, N.V., Sugi, M.D., Caserta, M.P. et al. “Sea urchin sign”: a radiological indicator of fibrotic deep infiltrating endometriosis. Abdom Radiol 51, 912–915 (2026). https://doi.org/10.1007/s00261-025-05053-0 Received: Revised: Accepted: Published: Version of record: Issue date: DOI: https://doi.org/10.1007/s00261-025-05053-0