Prevalence of negative sliding sign representing pouch of Douglas obliteration during pelvic transvaginal ultrasound for any indication

Abstract

Objectives Pouch of Douglas (POD) obliteration can be predicted with a high degree of certainty and reproducibility using the dynamic transvaginal ultrasound (TVS) sliding‐sign technique. So far, studies on POD obliteration prediction have focused on tertiary‐care populations with high prevalence of endometriosis; however, POD obliteration may exist in individuals with asymptomatic endometriosis or other conditions. Our primary aim was to determine the prevalence of a negative sliding sign, representing POD obliteration, in a cohort of patients undergoing TVS for any gynecological indication. Methods This was a prospective observational study of consecutive women with an indication for gynecological TVS, conducted at a high‐volume ultrasound practice between July and August 2018. Clinical and surgical history, indication for TVS and TVS findings were documented. The prevalence of TVS‐confirmed POD obliteration, determined by interpretation of the sliding sign, was calculated for the entire cohort and for the subgroups of women with and without risk factors for endometriosis. High risk for endometriosis was defined as having (1) a TVS referral for endometriosis‐like pelvic pain or endometriosis specifically and/or (2) clinical symptoms or signs suggestive of endometriosis. Low risk was defined as the absence of these characteristics. Results During the study period, 1043 consecutive women underwent TVS. After excluding those who underwent transabdominal ultrasound, had a history of hysterectomy or with missing data, 909 women were analyzed. The prevalence of a negative sliding sign in the entire cohort was 47/909 (5.2%). A negative sliding sign was observed in 22/639 (3.4%) women with a low risk for endometriosis and 25/243 (10.3%) of those with a high risk for endometriosis (difference in proportions, 6.9% (95% CI 2.8–10.9%); P < 0.001). Conclusions We have demonstrated an overall prevalence of a negative sliding sign, suggesting POD obliteration, of 5.2% (or 1/20) in women seeking TVS for a gynecological indication. The prevalence of negative sliding sign in low‐risk women is not negligible (3.4% or 1/29 women). These women are most likely to have asymptomatic endometriosis or another important etiology of POD obliteration. The prevalence of a negative sliding sign is approximately three‐times higher in women with signs and/or symptoms of endometriosis (10.3% vs 3.4%). Copyright © 2020 ISUOG. Published by John Wiley & Sons Ltd.

One‐Size‐Fits‐All Approach Does Not Work for Gynecology Trainees Learning Endometriosis Ultrasound Skills

“…The dynamic nature of TVUS necessitates correct performance even before interpretation, so we believe it is crucial for there to be supervision during any learning program. In a recent publication on POD obliteration performed by sonographers in the absence of an ES, we highlighted the possibility that inadequate detection of the sliding sign may lead to an inflated classification of a negative sliding sign 28 . Finally, we also considered the notion that perhaps trainees with greater prior US experience may require less training to become competent with diagnosis of POD obliteration and bowel DE than trainees with less experience; thus, to test this hypothesis, our study incorporated a number of trainees with differing past US experience.…”

“…Although not part of the official educational program, all fellows attended the same lectures and academic presentations on endometriosis at the 27th World Congress on Ultrasound in Obstetrics and Gynecology 3 months before patient recruitment. Nodule with regular outline 8 (32) Nodule with progressive narrowing ("comet" sign) 3 (12) Nodule with prominent spikes to bowel lumen ("moose antler" sign) 7 (28) Nodule with moose antler and comet sign 1 (4) Nodule with moose antler sign and extrinsic retraction (and visible mucosal folds: "pulling sleeve" sign) 6 (24)…”

“…In a recent publication on POD obliteration performed by sonographers in the absence of an ES, we highlighted the possibility that inadequate detection of the sliding sign may lead to an inflated classification of a negative sliding sign. 28 Finally, we also considered the notion that perhaps trainees with greater prior US experience may require less training to become competent with diagnosis of POD obliteration and bowel DE than trainees with less experience; thus, to test this hypothesis, our study incorporated a number of trainees with differing past US experience. To our knowledge, no other previous comparable study attempted to capture the learning curve of gynecologic trainees with variable but overall substantially less experience in US in a realtime setting.…”

Deep learning to diagnose pouch of Douglas obliteration with ultrasound sliding sign

“…it is thought that roughly 1 in 29 women without concern for endometriosis have POD obliteration (Leonardi et al, 2020a). It is well understood that recognizing POD obliteration non-invasively is crucial (Tompsett et al, 2019;Espada et al, 2021).…”

The Emergence of the Gynecologic Surgeon Sonologist as the Conductor of Complex Gynecologic Surgery

“…A negative sliding sign, equating to an obliterated rectouterine pouch, is a clear indication that surgery will be complex and should only be undertaken by a surgeon with advanced skill. Likewise, the sliding sign may be useful beyond endometriosis surgery and applied preoperatively in all patients who are planned for hysterectomy for similar surgical complexity prediction 4 . The ideal person to perform these ultrasound scans is the Gynecologic Surgeon Sonologist because of the dynamic nature unique to ultrasound compared to other imaging modalities.…”