{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,17]],"date-time":"2026-09-17T11:05:26Z","timestamp":1789643126156,"version":"4.0.0"},"reference-count":20,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2026,9,17]],"date-time":"2026-09-17T00:00:00Z","timestamp":1789603200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Medicina"],"abstract":"<jats:p>Background and Objective: The ultrasound sliding sign dynamically assesses pouch of Douglas (POD) obliteration in suspected endometriosis. Transvaginal (TVS) and transrectal (TRS) ultrasound are used in patients with and without a self-reported history of vaginal intercourse, respectively, and thus in clinically distinct populations. We evaluated sliding sign performance for predicting surgically confirmed complete POD obliteration in patients with ovarian endometriomas and described findings in route-defined TVS and TRS groups. Materials and Methods: This retrospective cohort study enrolled 318 patients with surgically and pathologically confirmed ovarian endometriomas; intraoperative POD status was evaluable in 309. Patients with and without a self-reported history of vaginal intercourse underwent TVS (n = 247) and TRS (n = 71), respectively. A negative sliding sign (absent movement between the uterus and rectum) was the positive index test result for complete POD obliteration. The unadjusted full-cohort diagnostic accuracy analysis was the primary analysis. Because no parous patient underwent TRS (a lack of overlap in examination-route assignment among parous patients), exploratory adjusted analyses were restricted to nulliparous patients, using overlap weighting (principal adjusted analysis) and 1:1 propensity score matching (sensitivity analysis). Results: In the primary unadjusted analysis of the full cohort (n = 309), the negative sliding sign showed limited to moderate discriminative ability (sensitivity 0.71, 95% CI 0.63\u20130.78; specificity 0.60, 95% CI 0.52\u20130.67; PLR 1.78, 95% CI 1.44\u20132.20; NLR 0.48, 95% CI 0.36\u20130.64) and was associated with complete POD obliteration (p &lt; 0.001). The between-route sensitivity difference was inconclusive (0.19, 95% CI \u22120.01 to 0.38). In the exploratory overlap-weighted analysis of nulliparous patients (n = 217), the association remained significant (weighted OR = 2.80, 95% CI 1.17\u20136.69; p = 0.021), without significant sliding sign-by-route interaction (p = 0.302); findings were consistent in the matching sensitivity analysis (66 pairs). Conclusions: The sliding sign was associated with surgically confirmed complete POD obliteration in patients with ovarian endometriomas, but evidence that this association differed between route-defined groups was inconclusive. Route-specific findings are exploratory because the examination route was determined by sexual history rather than randomization. Whether TRS offers performance comparable to TVS remains undetermined, because the two techniques were not evaluated in the same population and TRS feasibility was not formally assessed.<\/jats:p>","DOI":"10.3390\/medicina62091791","type":"journal-article","created":{"date-parts":[[2026,9,17]],"date-time":"2026-09-17T09:59:03Z","timestamp":1789639143000},"page":"1791","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Ultrasound Sliding Sign Assessed by Transvaginal or Transrectal Route for Predicting Complete Pouch of Douglas Obliteration in Patients with Ovarian Endometriomas: An Exploratory Retrospective Study"],"prefix":"10.3390","volume":"62","author":[{"given":"Dong","family":"Liu","sequence":"first","affiliation":[{"name":"Department of Gynecology, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou 510630, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"software","vocabulary":"credit"},{"role":"validation","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"}]},{"given":"Huanli","family":"He","sequence":"additional","affiliation":[{"name":"Department of Gynecology, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou 510630, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuebo","family":"Yang","sequence":"additional","affiliation":[{"name":"Department of Gynecology, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou 510630, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8455-6967","authenticated-orcid":false,"given":"Qingjian","family":"Ye","sequence":"additional","affiliation":[{"name":"Department of Gynecology, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou 510630, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"827","DOI":"10.1093\/humrep\/den464","article-title":"Rich innervation of deep infiltrating endometriosis","volume":"24","author":"Wang","year":"2009","journal-title":"Hum. Reprod."},{"key":"ref_2","first-page":"209","article-title":"Anatomical distribution of pelvic deep infiltrating endometriosis and its relationship with pain symptoms","volume":"125","author":"Dai","year":"2012","journal-title":"Chin. Med. J."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"20","DOI":"10.1016\/j.ejogrb.2021.05.044","article-title":"Coexistence of endometriomas with extraovarian endometriosis and adhesions","volume":"263","author":"Piriyev","year":"2021","journal-title":"Eur. J. Obstet. Gynecol. Reprod. Biol."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"685","DOI":"10.1002\/uog.12305","article-title":"Prediction of pouch of Douglas obliteration in women with suspected endometriosis using a new real-time dynamic transvaginal ultrasound technique: The sliding sign","volume":"41","author":"Reid","year":"2013","journal-title":"Ultrasound Obstet. Gynecol."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"236","DOI":"10.1530\/RAF-21-0031","article-title":"Deep learning to diagnose pouch of Douglas obliteration with ultrasound sliding sign","volume":"2","author":"Maicas","year":"2021","journal-title":"Reprod. Fertil."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"e9536","DOI":"10.1097\/MD.0000000000009536","article-title":"Diagnostic accuracy of magnetic resonance imaging, transvaginal, and transrectal ultrasonography in deep infiltrating endometriosis","volume":"97","author":"Alborzi","year":"2018","journal-title":"Medicine"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"625","DOI":"10.1111\/resp.12312","article-title":"Introduction to propensity scores","volume":"19","author":"Williamson","year":"2014","journal-title":"Respirology"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"477","DOI":"10.1002\/uog.24900","article-title":"Diagnostic accuracy of sliding sign for detecting pouch of Douglas obliteration and bowel involvement in women with suspected endometriosis: Systematic review and meta-analysis","volume":"60","author":"Eguez","year":"2022","journal-title":"Ultrasound Obstet. Gynecol."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"928","DOI":"10.1016\/j.jmig.2018.09.777","article-title":"Prediction of Pouch of Douglas Obliteration: Point-of-care Ultrasound Versus Pelvic Examination","volume":"26","author":"Arion","year":"2019","journal-title":"J. Minim. Invasive Gynecol."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"1219","DOI":"10.1002\/jum.15505","article-title":"Transvaginal Ultrasound Findings After Laparoscopic Rectosigmoid Segmental Resection for Deep Infiltrating Endometriosis","volume":"40","author":"Martire","year":"2021","journal-title":"J. Ultrasound Med."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"265","DOI":"10.1016\/j.jmig.2019.08.027","article-title":"Sonographic Evaluation for Endometriosis in Routine Pelvic Ultrasound","volume":"27","author":"Piessens","year":"2020","journal-title":"J. Minim. Invasive Gynecol."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"253","DOI":"10.1002\/uog.17465","article-title":"Accuracy of preoperative real-time dynamic transvaginal ultrasound sliding sign in prediction of pelvic adhesions in women with previous abdominopelvic surgery: Prospective, multicenter, double-blind study","volume":"51","author":"Ayachi","year":"2018","journal-title":"Ultrasound Obstet. Gynecol."},{"key":"ref_13","doi-asserted-by":"crossref","unstructured":"Bal\u0131ko\u011flu, M., Tanyeri, U., K\u0131nc\u0131, M.F., Bozgeyik, M.B., and Akpak, Y.K. (2026). Diagnostic accuracy of the sonographic sliding sign for predicting pelvic organ adhesions in gynecologic endoscopic surgery. BMC Surg., 26.","DOI":"10.1186\/s12893-026-03523-w"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"118","DOI":"10.1002\/j.2205-0140.2013.tb00099.x","article-title":"The \u201csliding sign\u201d in conjunction with sonovaginography: Is this the optimal approach for the diagnosis of Pouch of Douglas obliteration and posterior compartment deep infiltrating endometriosis?","volume":"16","author":"Menakaya","year":"2013","journal-title":"Australas. J. Ultrasound Med."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"26","DOI":"10.4103\/jhrs.JHRS_169_19","article-title":"Sliding Sign and Gel Sonovaginography: A Sneak Peek Prior to Laparoscopy in Patients with Endometriosis","volume":"13","author":"Venkatesh","year":"2020","journal-title":"J. Hum. Reprod. Sci."},{"key":"ref_16","first-page":"118","article-title":"Relationship of pelvic clinic-pathological features and the pain symptoms in ovarian endometrioma","volume":"48","author":"Dai","year":"2013","journal-title":"Zhonghua Fu Chan Ke Za Zhi"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"437962","DOI":"10.1155\/2014\/437962","article-title":"Evaluation of the usefulness of the MRI jelly method for diagnosing complete cul-de-sac obliteration","volume":"2014","author":"Kikuchi","year":"2014","journal-title":"BioMed Res. Int."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"54","DOI":"10.1111\/1754-9485.13283","article-title":"MRI sliding sign: Using MRI to assess rectouterine mobility in pelvic endometriosis","volume":"66","author":"Fan","year":"2022","journal-title":"J. Med. Imaging Radiat. Oncol."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"5959","DOI":"10.2147\/JIR.S421389","article-title":"Plasma and Peritoneal Fluid Annexin A2 Levels in Patients with Endometriosis","volume":"16","author":"Zygarowicz","year":"2023","journal-title":"J. Inflamm. Res."},{"key":"ref_20","doi-asserted-by":"crossref","unstructured":"Kacperczyk-Bartnik, J., Bartnik, P., Go\u0142awski, K., Sierdzi\u0144ski, J., Ma\u0144ka, G., Kiecka, M., Lipa, M., Warzecha, D., Spaczy\u0144ski, R., and Piekarski, P. (2022). Plasma and Peritoneal Poly (ADP-Ribose) Polymerase Levels in Patients with Endometriosis. Biomedicines, 10.","DOI":"10.3390\/biomedicines10102451"}],"container-title":["Medicina"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1648-9144\/62\/9\/1791\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,9,17]],"date-time":"2026-09-17T11:01:27Z","timestamp":1789642887000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1648-9144\/62\/9\/1791"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,9,17]]},"references-count":20,"journal-issue":{"issue":"9","published-online":{"date-parts":[[2026,9]]}},"alternative-id":["medicina62091791"],"URL":"https:\/\/doi.org\/10.3390\/medicina62091791","relation":{},"ISSN":["1648-9144"],"issn-type":[{"value":"1648-9144","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,9,17]]}}}