Pouch Of Douglas Obliteration Research Articles

Laparoscopic Modified Radical Hysterectomy for Severe Endometriosis: A Single-Center Case Series

Study objectiveThe main objective is to describe the feasibility and report a single centre experience of a standardized laparoscopic modified radical hysterectomy technique among patients with severe endometriosis and pouch of Douglas obliteration. DesignA single-center case series of laparoscopic modified radical hysterectomy performed at the Poissy Hospital between December 2012 and May 2021. SettingsSingle-center, gynecology unit (level III) with a focus on endometriosis. PatientsPatients with severe endometriosis (stage 4 AFS) and pouch of Douglas Obliteration. Measurements and Main ResultsFifty-two patients with severe endometriosis underwent the surgical procedure.Out of these patients: 23.1% underwent a rectal shaving (n= 12), 1.9 % a discoid resection (n= 1) and 17.3% a rectal resection (n= 9), including a protective ileostomy in one case. Ureterolysis was performed on 82.7% of patients (n= 43). The average hospital stay was 3.3 days (1-12). Seven patients required intermittent self-catheterization (13.5%). Minor complications (Clavien-Dindo grade 1 and 2) occurred to 25.9% of the patients and severe complications to 3.8% of them (Clavien-Dindo grade 3, no grade 4). Two patients (3.8%) were reoperated: one for a postoperative occipital alopecia (balding) and the other for vaginal dehiscence with evisceration. About 50 patients (96.2%) had a complete resection of endometriosis. The median follow-up was 14 months (interquartile range 6-23 months) with 94.3% of them improved (much and very much) and 3.8% minimally improved. ConclusionIn our experience, laparoscopic modified radical hysterectomy is a reliable procedure with a low rate of severe complications. This technique needs to be assessed by other surgeons and others centers across the country and abroad, in order to determine the likehood of it succeeding.

#122 : Extrapolating Endometriosis Diagnosis Using Imaging and Machine Learning: The Imagendo Project

Background and Aims: Currently, it takes an average of 6.4 years to obtain a diagnosis for endometriosis. To address this delay, the IMAGENDO project combines ultrasounds (eTVUS) and Magnetic Resonance Images (eMRI) using Artificial Intelligence (AI). Our preliminary data has shown that a multimodal AI approach objectively assesses imaging data from eTVUS and eMRIs and improves diagnostic accuracy for endometriosis. Our first example shows how automated detection of Pouch of Douglas (POD) obliteration can be augmented by a novel multimodal approach. Aim: To improve eMRI detection of POD obliteration, by leveraging detection results from unpaired eTVUS data. Method: Retrospective specialist private and public imaging datasets of the female pelvis were obtained. After pre-training a machine learning model using 8,984 MRIs from a public dataset, we fine-tuned the algorithm using 88 private eMRIs, to detect POD obliteration. We then introduced another 749 unpaired eTVUSs to further improve our diagnostic model. Results: To resolve confounding problems with our eMRI datasets due to artefacts, mislabelling, and misreporting, we used model checking, student auditing and expert radiology review. Our results illustrated effective multimodal analysis methods which improved the POD obliteration detection accuracy from eMRI datasets. This model improved the Area Under the Curve (AUC) from 65.0% to 90.6%. Conclusion: We have been able to improve the accuracy of diagnosing endometriosis from eMRIs using a novel POD obliteration detection method. Our method extracts knowledge from unpaired eTVUSs and applies it to eMRI datasets. The detection of POD obliteration is automated from eMRI data. Combining images for corresponding endometriosis signs using algorithms, is the first step in improving the imaging diagnosis of endometriosis, when compared to surgery, and allows extrapolation of results when either imaging modality is missing. This will enable women to obtain a faster diagnosis, where adequate scanning is available, prior to undertaking surgery.

Adenomyosis and Endometriomas & Assessing the Rectosigmoid Colon

Endometriosis is a common and often debilitating gynaecological disorder that affects 5-10% of women. The prevalence is even higher among women with symptoms of endometriosis. Approximately 80% of women suffering from endometriosis have superficial lesions while 20% have deep infiltrating endometriosis. Laparoscopy has always been considered the gold standard for diagnosing endometriosis as it allows diagnosis of both forms of endometriosis and often immediate removal of superficial endometriosis. The removal of deep infiltrating endometriosis is however significantly more complex, particularly when pouch of Douglas obliteration, bowel nodules or bladder nodules are present. Unless it was diagnosed preoperatively, the removal can usually not be completed because a multidisciplinary approach is often required with the involvement of a urologist or a colorectal surgeon. Over the last 15 years it has been well established in the literature that transvaginal ultrasound allows preoperative diagnosis of deep infiltrating endometriosis. The preoperative diagnosis of DIE with transvaginal ultrasound facilitates a more patient-centred approach to endometriosis management because an accurate preoperative documentation of the location and extent of the disease allows for referral to an endometriosis expert and/or bowel surgeon, better preoperative planning, less repetitive surgery, and better outcomes for women. The presentation on ‘Endometriomas and Adenomyosis’ will highlight the importance of these findings as red flags for the presence of deep endometriosis but also touch on how these conditions change over time with pregnancy and menopause. The presentation on ‘Assessing the rectosigmoid colon’ gives an overview on how to systematically assess the rectosigmoid for the presence of deep endometriosis nodules, and when this assessment must be included in the assessment of the pelvis.

Diagnostic Accuracy of Transvaginal Sonography for Deeply Infiltrating Endometriosis and Pouch of Douglas Obliteration in the Presence or Absence of Ovarian Endometrioma

Background: Endometriosis is one of the most common gynecological diseases worldwide. Significant attention has been drawn to this multiorgan and often painful disorder. Objectives: This study aimed to examine the accuracy of transvaginal sonography (TVS) in the diagnosis of deeply infiltrating endometriosis (DIE) with respect to the presence or absence of ovarian endometrioma (OE). Patients and Methods: This cross-sectional study was performed on all patients undergoing TVS before gynecological laparoscopy. With pathological confirmation as the standard reference, the diagnostic accuracy of TVS for DIE and pouch of Douglas (POD) obliteration was compared with that of laparoscopy in the anterior and posterior pelvic compartments with respect to the presence or absence of OE. Agreement between TVS and laparoscopy was evaluated for each case, and Cohen’s kappa statistic was measured for each site of involvement. Moreover, sensitivity, specificity, negative and positive predictive values, and likelihood ratios of TVS were calculated, with laparoscopy as the reference test. Results: A total of 110 patients, with a mean age of 37.20 ± 7.16 years, were recruited in this study. The accuracy, sensitivity, and negative predictive value of TVS for the diagnosis of DIE and POD obliteration were estimated at 89.5%, 58.3%, and 88.9% in the anterior pelvic compartment and 93.3%, 92%, and 70.6% in the posterior pelvic compartment, respectively. Nevertheless, TVS showed lower sensitivity for detecting pelvic adhesions and peritoneal cysts compared to laparoscopy. The presence of OE did not significantly increase the accuracy of TVS for the diagnosis of DIE or POD obliteration (P > 0.05). Conclusion: The present study showed that TVS is an adequately accurate and non-invasive diagnostic tool for the detection and mapping of DIE and POD obliteration, regardless of the presence of OE. TVS may waive the need for exploratory laparoscopy in DIE or at least facilitate precise pre-procedural DIE mapping.

Anatomical distribution of endometriosis: Across-sectional analysis of transvaginal ultrasound in symptomatic patients.

The anatomical distribution of deep endometriosis (DE) is essential in treating patients with symptoms associated with the disease. There is an evidence gap in correlating clinical features and symptoms with disease patterns. The study aimed at determining DE anatomic distribution based on advanced transvaginal ultrasound and describe the relationship with symptoms obtained with the World Endometriosis Foundation Questionnaire. A cross-sectional study included 549 ultrasound results and 370 questionnaire responses between July 2018 and January 2021. Descriptive statistics are presented. Continuous variables were compared by a simple t-test and ANOVA and categorical variables by the chi-squared test. Logistic regression and R2 values summarised the relationship between positive ultrasound and possible predictor variables (software SAS version 9.4). The anatomical locations with signs of endometriosis on ultrasound were the right uterosacral ligament (USL) 23.3% (n=128), left USL 21.3% (n=117) and bowel 19.1% (n=105). Endometriomas in the right and left ovaries (14%, n=77, and 14.7%, n=81 respectively), superficial endometriosis in 15.5% (n=85), torus uterinus in 11.7% (n=64), Pouch of Douglas (POD) in 9.7% (n=53), rectovaginal septum in 4.2% (n=23), vaginal fornix in 3.5% (n=19). A negative 'sliding-sign' was noted in 25.3% (n=139), and ovarian medial immobility was noted frequently (left 20.2%, n=111 and right 16.9%, n=93). Dyspareunia, dysmenorrhoea, infertility and family history were associated with endometriosis lesions (P < 0.05). Prediction models based on symptomatology presented low discriminatory power. This large real-life cohort associating the description of the anatomical distribution of endometriosis as seen on advanced TVS in symptomatic patients confirmed that uterosacral ligaments, torus uterinus, ovaries and bowel represent the most common anatomical sites of endometriosis. Also, the dynamic abnormalities elicited via ultrasound, such as the uterus 'sliding-sign' and ovarian mobility, remain common. The knowledge of the general locations of identifiable endometriosis on ultrasound and the dynamic abnormalities is essential to sonologists and sonographers in implementing advanced TVS protocols to detect endometriosis. In addition, the different presentations of dyspareunia can be associated with USL and bowel endometriosis. Subfertility might also be associated with USL, ovarian and bowel endometriosis. Nevertheless, prediction models showed suboptimal results. Endometriosis is mainly distributed in USLs, bowel and ovaries. POD obliteration is frequent. Symptoms can be associated with anatomic locations; however, prediction models showed low clinical applicability.

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

ObjectivesPouch of Douglas (POD) obliteration is a severe consequence of inflammation in the pelvis, often seen in patients with endometriosis. The sliding sign is a dynamic transvaginal ultrasound (TVS) test that can diagnose POD obliteration. We aimed to develop a deep learning (DL) model to automatically classify the state of the POD using recorded videos depicting the sliding sign test.MethodsTwo expert sonologists performed, interpreted, and recorded videos of consecutive patients from September 2018 to April 2020. The sliding sign was classified as positive (i.e. normal) or negative (i.e. abnormal; POD obliteration). A DL model based on a temporal residual network was prospectively trained with a dataset of TVS videos. The model was tested on an independent test set and its diagnostic accuracy including area under the receiver operating characteristic curve (AUC), accuracy, sensitivity, specificity, and positive and negative predictive value (PPV/NPV) was compared to the reference standard sonologist classification (positive or negative sliding sign).ResultsIn a dataset consisting of 749 videos, a positive sliding sign was depicted in 646 (86.2%) videos, whereas 103 (13.8%) videos depicted a negative sliding sign. The dataset was split into training (414 videos), validation (139), and testing (196) maintaining similar positive/negative proportions. When applied to the test dataset using a threshold of 0.9, the model achieved: AUC 96.5% (95% CI: 90.8–100.0%), an accuracy of 88.8% (95% CI: 83.5–92.8%), sensitivity of 88.6% (95% CI: 83.0–92.9%), specificity of 90.0% (95% CI: 68.3–98.8%), a PPV of 98.7% (95% CI: 95.4–99.7%), and an NPV of 47.7% (95% CI: 36.8–58.2%).ConclusionsWe have developed an accurate DL model for the prediction of the TVS-based sliding sign classification.Lay summaryEndometriosis is a disease that affects females. It can cause very severe scarring inside the body, especially in the pelvis − called the pouch of Douglas (POD). An ultrasound test called the 'sliding sign' can diagnose POD scarring. In our study, we provided input to a computer on how to interpret the sliding sign and determine whether there was POD scarring or not. This is a type of artificial intelligence called deep learning (DL). For this purpose, two expert ultrasound specialists recorded 749 videos of the sliding sign. Most of them (646) were normal and 103 showed POD scarring. In order for the computer to interpret, both normal and abnormal videos were required. After providing the necessary inputs to the computer, the DL model was very accurate (almost nine out of every ten videos was correctly determined by the DL model). In conclusion, we have developed an artificial intelligence that can interpret ultrasound videos of the sliding sign that show POD scarring that is almost as accurate as the ultrasound specialists. We believe this could help increase the knowledge on POD scarring in people with endometriosis.

Ovarian Immobility at Transvaginal Ultrasound: An Important Sonographic Marker for Prediction of Need for Pelvic Sidewall Surgery in Women With Suspected Endometriosis.

To determine whether ovarian fixation at transvaginal ultrasound (TVU) is a marker for a need for laparoscopic pelvic sidewall surgery (ie,ureterolysis or dissection of adhesions involving the pelvic sidewall). The relationship between ovarian immobility at TVU with respect to endometriosis staging using the revised American Fertility Society (r-AFS) classification was also evaluated. Retrospective diagnostic accuracy study was performed in a tertiary referral hospital and two private hospitals. Sixty-six women with pelvic pain underwent detailed TVU preoperatively followed by laparoscopic endometriosis surgery. TVU ovarian mobility findings (ie, mobile versus fixed ovary) were compared to surgical findings, the need for laparoscopic pelvic sidewall surgery and r-AFS score (I-IV). Complete ultrasound and surgical data were available for 66 of 77 (86%) women. Twenty-six of 66 (40%) had isolated superficial peritoneal endometriosis, 15 of 66 (23%) had ovarian endometrioma (OE), 13 of 66 (20%) had pelvic deep endometriosis (DE). Twenty-seven of 66 (41%) had ovarian fixation at TVU. The accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of ovarian fixation at TVU for the prediction of need for laparoscopic pelvic sidewall surgery was 71%, 61%, 86%, 85%, and 62%, respectively (P=.0002). Ovarian fixation at TVU was significantly associated with the presence of ipsilateral OE, pouch of Douglas obliteration, pelvic DE nodules, and r-AFS stage III/IV (moderate/severe) endometriosis (all P-values <.05). Ovarian fixation at TVU appears to be a marker for moderate/severe endometriosis and the need for laparoscopic pelvic sidewall surgery. This sign may be a valuable "red flag" for identifying women at increased risk of requiring an advanced laparoscopic surgeon, and in turn, improve surgical planning.

Role of preoperative ultrasound mapping in the surgical management of deep infiltrating endometriosis: a prospective observational study

BackgroundEndometriosis is a challenging gynecological condition that has a profound influence on the quality of life of affected women. Transvaginal ultrasound is considered the first-line imaging method in preoperative assessment of the extent and severity of endometriosis. Accurate preoperative mapping can aid the surgeon in patient counselling, selection of the most appropriate surgical method that minimizes the operative and post-operative complications. The aim of our study is to evaluate the accuracy of transvaginal sonography (TVS) in precisely assessing the size, location and extent of deep infiltrating endometriosis (DIE) using a new modified endometriosis mapping proforma with histopathological confirmation. Our prospective observational study included 101 women with clinically suspected DIE who underwent TVS followed by laparoscopy from October 2018 to December 2020 with a maximum of 4 weeks interval. Precise mapping of DIE was done during TVS and laparoscopy. Results were correlated with histopathology findings.ResultsDIE was confirmed by histopathology in 88 patients. Sensitivity and specificity for individual DIE locations were rectovaginal septum 67.9% and 98.6%; vagina 52.2% and 98.7%; uterosacral ligaments 82.5% and 96.2%; torus 96.4% and 97.3%; parametrium 68.8% and 96.9%; rectum 100% and 98.8%; bladder 100% and 100%, ureters 63.4% and 99.0%; scar endometriosis 100% and 100%; pouch of Douglas obliteration 97.7% and 100%. No statistically significant difference was detected between ultrasound and histopathology size. Ultrasound tended to underestimate the lesion size; the underestimation was more pronounced for lesions > 3 cm. “Butterfly” and “tram-track” signs are two new sonographic signs related to posterior compartment DIE. No post-operative complications were recorded. There were no cases of DIE recurrence. Eleven out of 22 cases of infertility achieved pregnancy during 18 months follow-up.ConclusionTVS provides a thorough and accurate evaluation of the extent of endometriosis. An experienced radiologist can use E-PEP to provide an accurate demonstration of the location and extent of DIE which helps the surgeon select the most appropriate surgical approach ensuring radical treatment of the disease and minimizing short- and long-term complications.

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

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. 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. 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). 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.

International survey finds majority of gynecologists are not aware of and do not utilize ultrasound techniques to diagnose and map endometriosis.

International survey finds majority of gynecologists are not aware of and do not utilize ultrasound techniques to diagnose and map endometriosis.

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

To evaluate whether gynecologic surgical trainees (fellows) can become competent in the real-time classification of the pouch of Douglas (POD) obliteration state and direct visualization of bowel deep endometriosis (DE) during a program with a prespecified number of transvaginal ultrasound (TVUS) examinations. We performed a prospective study between December 2017 and December 2018. Three fellows (F1-F3) performed 50 scans each, which were all supervised by an expert sonologist, who performed the reference standard TVUS examination. The fellows performed a focused TVUS examination to assess the bowel and POD state, having been blinded to the patient's clinical history and reference standard findings. Immediate feedback and hands-on teaching were provided after each of the fellow's official classifications. To evaluate the number of scans needed to gain competency, the cumulative summation test for the learning curve was used. A total of 150 examinations were performed on 145 patients. Twenty-six (17.9%) patients had a diagnosis of bowel DE, and 34 (23.4%) were classified as having a negative sliding sign by the reference standard. The overall accuracy of the presence/absence of bowel DE was 90% (range, 82%-94%). The overall accuracy of POD state classification was 93% (range, 90%-96%). The cumulative summation test for the learning curve for bowel DE showed that F1 did not reach competency by 50 scans, whereas F2 and F3 required 21 and 25 scans, respectively. For POD obliteration, F2 did not reach competency, whereas F1 and F3 required 40 and 22 scans. Not all trainees can reach competency for TVUS evaluations of POD obliteration and bowel DE in a predefined number of scans.

Intra- and interobserver reproducibility of pelvic ultrasound for the detection and measurement of endometriotic lesions.

STUDY QUESTIONWhat is the interobserver and intraobserver reproducibility of pelvic ultrasound for the detection of endometriotic lesions?SUMMARY ANSWERPelvic ultrasound is highly reproducible for the detection of pelvic endometriotic lesions.WHAT IS KNOWN ALREADYTransvaginal ultrasound (TVS) has been widely adopted as the first-line assessment for the diagnosis and assessment of pelvic endometriosis. Severity of endometriosis as assessed by ultrasound has been shown to have good concordance with laparoscopy (kappa 0.79). The reproducibility of TVS for assessment of ovarian mobility and pouch of Douglas obliteration using the ‘sliding sign’ has already been described in the literature. However, there is no available data in the literature to demonstrate the intraobserver repeatability of measurements for endometriotic cysts and nodules.STUDY DESIGN, SIZE, DURATIONThis was a prospective observational cross-sectional study conducted over a period of 12 months. We included 50 consecutive women who were all examined by two operators (A and B) during their clinic attendance.PARTICIPANTS/MATERIALS, SETTING, METHODSThe study was carried out in a specialist endometriosis centre. We included all consecutive women who had ultrasound scans performed independently by two experienced operators during the same visit to the clinic. The outcomes of interest were the inter- and intraobserver reproducibility for the detection of endometriotic lesions. We also assessed repeatability of the measurements of lesion size.MAIN RESULTS AND THE ROLE OF CHANCEThere was a good level of agreement between operator A and operator B in detecting the presence of pelvic endometriotic lesions (k = 0.72). There was a very good level of agreement between operators in identifying endometriotic cysts (k = 0.88) and a good level of agreement in identifying endometriotic nodules (k = 0.61). The inter- and intraobserver repeatability of measuring endometriotic cysts was excellent (intra-class correlation (ICC) ≥ 0.98). There was good interobserver measurement repeatability for bowel nodules (ICC 0.88), but the results for nodules in the posterior compartment were poor (ICC 0.41). The intraobserver repeatability for nodule size measurements was good for both operators (ICC ≥0.86).LIMITATIONS, REASONS FOR CAUTIONWithin this cohort, there was insufficient data to perform a separate analysis for nodule size in the anterior compartment. All examinations were performed within a specialised unit with a high prevalence of deep endometriosis. Our findings may not apply to operators without intensive ultrasound training in the diagnosis of pelvic endometriosis.WIDER IMPLICATIONS OF THE FINDINGSThese findings are important because ultrasound has been widely accepted as the first-line investigation for the diagnosis of pelvic endometriosis, which often determines the need for future investigations and treatment. The detection and measurement of bowel nodules is essential for anticipation of surgical risk and planning surgical excision.STUDY FUNDING/COMPETING INTEREST(S)The authors have no conflict of interest. No funding was obtained for this work.

Diagnostic Accuracy of Ultrasound and MRI in the Mapping of Deep Pelvic Endometriosis Using the International Deep Endometriosis Analysis (IDEA) Consensus.

Objectives The primary aim was to investigate the diagnostic accuracy of transvaginal ultrasound (TVS) and magnetic resonance imaging (MRI) in the mapping of deep pelvic endometriosis (DE) in a diseased population. The secondary aim was to offer first insights into the clinical applicability of the new International Deep Endometriosis Analysis group (IDEA) consensus for sonographic evaluation, which was also adapted for MRI and surgical reporting in this study. Methods The study was a prospective observational cohort study. In this study, consecutive women planned for surgical treatment for DE underwent preoperative mapping of pelvic disease using TVS and MRI (index tests). The results were compared against the intraoperative findings with histopathological confirmation (reference standard). In case of disagreement between intraoperative and pathology findings, the latter was prioritised. Index tests and surgical findings were reported using a standardised protocol based on the IDEA consensus. Results The study ran from 07/2016 to 02/2018. One-hundred and eleven women were approached, but 60 declined participation. Out of the 51 initially recruited women, two were excluded due to the missing reference standard. Both methods (TVS and MRI) had the same sensitivity and specificity in the detection of DE in the upper rectum (UpR) and rectosigmoid (RS) (UpR TVS and MRI sensitivity and specificity 100%; RS TVS and MRI sensitivity 94%; TVS and MRI specificity 84%). In the assessment of DE in the bladder (Bl), uterosacral ligaments (USL), vagina (V), rectovaginal septum (RVS), and overall pelvis (P), TVS had marginally higher specificity but lower sensitivity than MRI (Bl TVS sensitivity 89%, specificity 100%, MRI sensitivity 100%, specificity 95%; USL TVS sensitivity 74%, specificity 67%, MRI sensitivity 94%, specificity 60%; V TVS sensitivity 55%, specificity 100%, MRI sensitivity 73%, specificity 95%; RVS TVS sensitivity 67%, specificity 100%, MRI sensitivity 83%, specificity 93%; P TVS sensitivity 78%, specificity 97%, MRI sensitivity 91%, specificity 91%). No significant differences in diagnostic accuracy between TVS and MRI were observed except USL assessment (p=0.04) where MRI was significantly better and pouch of Douglas obliteration (p=0.04) where MRI was significantly better and pouch of Douglas obliteration (κ) = 0.727 [p=0.04) where MRI was significantly better and pouch of Douglas obliteration (κ) = 0.727 [p=0.04) where MRI was significantly better and pouch of Douglas obliteration (p=0.04) where MRI was significantly better and pouch of Douglas obliteration (Conclusion We found that both imaging techniques had overall good agreement with the reference standard in the detection of deep pelvic endometriosis. This is the first study to date involving the IDEA consensus for ultrasound, its modified version for MRI, and intraoperative reporting of deep pelvic endometriosis in clinical practice.

Ultrasound evaluation of pouch of Douglas obliteration and rectal deep endometriosis in women who have had previous combined colorectal and gynaecological laparoscopic surgery for rectal endometriosis: A pilot study.

Ultrasound has been demonstrated to accurately diagnose rectal deep endometriosis (DE) and pouch of Douglas (POD) obliteration. The role of ultrasound in the assessment of patients who have undergone surgery for rectal DE and POD obliteration has not been evaluated. To describe the transvaginal ultrasound (TVS) findings of patients who have undergone rectal surgery for DE. An observational cross-sectional study at a tertiary care centre in Sydney, Australia between January and April 2017. Patients previously treated for rectal DE (low anterior resection vs rectal shaving/disc excision) were recruited and asked to complete a questionnaire on their current symptoms. On TVS, POD state and rectal DE were assessed. Correlating recurrence of POD obliteration and/or rectal DE to surgery type and symptoms was done. Fifty-six patients were contacted; 22/56 (39.3%) attended for the study visit. Average interval of surgery to study visit was 52.8±24.6months. Surgery type breakdown was as follows: low anterior resection (56%) and rectal shaving/disc excision (44%). The prevalence of POD obliteration was 16/22 (72.7%) intraoperatively and 8/22 (36.4%) at study visit, as per the sliding sign. Nine patients (39.1%) had evidence on TVS of recurrent rectal DE. Recurrence of POD obliteration and rectal DE was not associated with surgery type or symptomatology. Despite surgery for rectal DE, many patients have a negative sliding sign on TVS, representing POD obliteration, and rectal DE. Our numbers are too small to correlate with the surgery type or their current symptoms.

Sliding Sign and Gel Sonovaginography: A Sneak Peek Prior to Laparoscopy in Patients with Endometriosis.

Context:The rising incidence of endometriosis may be due to improvisation in the diagnostic techniques. Transvaginal sonography has proven to be very useful in the diagnosis of complexity of the disease and in turn to predict the intraoperative findings on laparoscopy.Aims:The aim was to study the use of sliding sign for detecting the status of the pouch of Douglas (POD) and to check for the presence of bowel and nonbowel deep infiltrating endometriosis (DIE) by gel sonovaginography.Settings and Design:This is a prospective observational study carried out patient division of Department of OBG in Kasturba Hospital Manipal.Methods:The study was carried out over a period of 2 years and included 136 women. After written informed consent, a detailed history and clinical examination was done. A detailed transvaginal sonography was done for each of the patients by a single observer on the Philips HD11XE machine two-dimensional transvaginal probe which included gel sonovaginography and real-time dynamic test called sliding sign.Statistical Analysis:Chi-square test was used in this study.Results:Sliding sign is highly specific, sensitive, and accurate for the detection of POD obliteration. It is 96.6% sensitive and 89.5% specific. It is 94.1% accurate and 94.5% positively predictive for the same. Transvaginal sonography is >92% specific for the detection of bowel and nonbowel DIE. The accuracy is over 91%. The negative predictability is 93.6% and 94.6%, respectively.Conclusions:Sliding sign is a useful, easy-to-perform, reproducible, and noninvasive modality for assessing the status of POD. Gel sonovaginography is also useful in accurately detecting the presence of deep infiltrating endometriotic deposits.

Comparison of Diagnostic Accuracy of Transvaginal Ultrasound for Deep Endometriosis and Pouch of Douglas Obliteration in The Presence and Absence of Ovarian Endometriomas

Study Objective We aim to evaluate and compare the diagnostic accuracy of deep endometriosis transvaginal ultrasound (DE TVS) in the presence and absence of ovarian endometriomas (OEs). Design This is a multicenter observational study of prospectively collected data. Setting Patients attended one of two gynecology-focused ultrasound practices and underwent laparoscopy at one of nine hospitals in the Sydney metropolitan area between 2009 and 2017. Patients or Participants Patients referred with suspected endometriosis. Interventions A DE TVS was performed in all patients and reported in a systematic fashion. Measurements and Main Results Surgical findings were the defined reference standard. Data were analyzed to determine the prevalence of surgically-diagnosed DE and pouch of Douglas (POD) obliteration in the presence or absence of OEs. DE TVS was assessed in terms of accuracy, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and positive (LR+) and negative (LR-) likelihood ratios. Comparison of DE TVS prediction of DE and POD obliteration in patients with versus those without OEs was performed. 410 patients were included. An OE was noted in 91, 22.2% patients (left: 66, 16.3%; right: 58, 14.2%; bilateral: 33, 8.2%). When comparing those with and without an OE, DE prevalence was 62/91, 68.1% and 81/313, 25.9%, respectively, and POD obliteration prevalence was 55/91, 60.4% and 31/313, 9.9%, respectively (p Conclusion The prevalence of DE and POD obliteration in patients without OEs is lower, but not negligible. Diagnostic accuracy of DE TVS is poorer in patients without OEs, which is not well understood and concerning as many patients may be falsely reassured.

1852 The Prevalence of Pouch of Douglas Obliteration Depicted on Basic Transvaginal Ultrasound by a Negative Sliding Sign in a General Population

Study Objective Pouch of Douglas (POD) obliteration can be predicted with a high degree of certainty in patients with symptoms of endometriosis using transvaginal ultrasound (TVS). Studies on POD obliteration and the sliding sign, as part of an expert-guided deep endometriosis (DE) TVS, have always focused on populations in tertiary care centres with high disease prevalence. Our aim is to determine the prevalence of a negative sliding sign on basic TVS in a general population. Design Prospective observational study. Setting Gynecology-focused ultrasound practice. Patients or Participants Consecutive patients visiting the practice for a gynecological TVS. Interventions The sliding sign was performed to determine the POD state. Measurements and Main Results Descriptive statistics were applied to the entire population and subgroups of patients high- and low-risk for endometriosis. High-risk for endometriosis was defined as having a TVS referral for endometriosis-related pelvic pain or specifically “endometriosis” and/or clinical symptoms suggestive of endometriosis. Low-risk was defined by the absence of these features. 1043 patients underwent TVS. Patients who underwent a transabdominal ultrasound (5.6%) and history of hysterectomy (1.3%) were excluded; 971 were eligible. The sliding sign was performed and interpreted in 922 patients. Prevalence of a negative sliding sign in the general, high-risk, and low-risk populations was 47/922 (5.1%), 25/243 (10.3%), 22/639 (3.4%) (p Conclusion We have shown that the prevalence of POD obliteration on ultrasound evaluation in the general population is roughly 1 in 20, which may serve as the foundation for future studies on the sliding sign in lower-risk populations as this dynamic ultrasound technique becomes increasingly understood and adopted.

Superficial Endometriosis can be Seen on Ultrasound: A Pilot Application of Saline-Infusion Sonopodography

Study Objective Saline-infusion sonoPODography (SPG) is a novel ultrasound procedure that involves introducing fluid into the pouch of Douglas (POD) via the uterus and tubes to create an acoustic window and enhanced contrast between tissues in the posterior compartment. We aim to demonstrate that SPG has utility in diagnosing superficial endometriosis (SE) in a non-invasive fashion. Design Prospective diagnostic accuracy study. Setting Tertiary healthcare center in Sydney, Australia from September 2018-March 2019. Patients or Participants Patients with symptoms of endometriosis planned for laparoscopy were recruited. Interventions SPG was done intra-operatively. Measurements and Main Results Laparoscopy was initiated to ascertain a reference standard visual diagnosis of endometriosis and to suction free fluid from the pelvis. The single SPG operator was blinded to this part of surgery. If fluid collected in the POD, SE of the posterior compartment was evaluated and compared to laparoscopic findings. SE on TVS was defined relative to peritoneal surfaces: 1) superficial hypoechoic areas, 2) hyperechoic projections, 3) cystic areas, 4) pockets of fluid, 5) filmy, irregular adhesions. 15/19 patients underwent successful SPG. Prevalence of overall endometriosis was 15/19 (79%); deep endometriosis (DE) 5/19 (26%); ovarian endometriomas 3/19 (16%); POD obliteration 2/19 (11%); SE 14/19 (74%). SPG diagnostic accuracy results are depicted in Table 1. Conclusion SPG was successfully completed in the majority of patients. In those without advanced endometriosis (i.e. POD obliteration), SPG is even more achievable and provides a reasonable sensitivity for overall SE and very good sensitivity for POD SE, which is the second most common site of SE. At present, SPG needs to be further evaluated but offers hope for a novel non-invasive diagnostic tool for SE.

1853 Learning Curve for the Detection of Pouch of Douglas Obliteration and Deep Endometriosis of the Rectum in Gynecology Trainees

Study Objective Evaluate the learning curve of gynecology trainees to correctly classify pouch of Douglas (POD) obliteration state and identify rectal deep endometriosis (DE) in real-time while simultaneously performing and interpreting transvaginal ultrasound (TVS). Design Learning curve using the cumulative sum (LCCUSUM) prospective study. Setting A tertiary healthcare center in Sydney, Australia. Patients or Participants Three observers of varying pre-study ultrasound experience. Interventions Observers performed a pre-determined 150 supervised examinations (50 each) to asses for POD obliteration and rectal DE, having been blinded to the clinical history and reference standard findings. Immediate feedback and hands-on teaching were provided. Measurements and Main Results The acceptable performance rate (proficiency) was set at 15% failure, the unacceptable performance rate was set at 30%, and the equivalence zone was set at 5%. 150 examinations were performed on 145 patients, with rectal DE in 26 (17.3%) and negative sliding sign in 34/145 (22.7%). The overall accuracy of presence or absence of rectal DE was 90%, ranging from 82-94% amongst the observers. The overall accuracy of POD state classification was 92.7%, ranging from 90-96% amongst the observers. LCCUSUM for rectal DE demonstrated observer 1 did not reach proficiency, whereas observers 2 and 3 required 21 and 25 scans, respectively. For POD obliteration, observer 2 did not reach proficiency, whereas observers 1 and 3 required 40 and 22 scans, respectively. Conclusion One gynecology trainee became proficient in diagnosing rectal DE and POD obliteration in less than the 50 planned supervised ultrasounds. Contrary to similar studies, we propose that not all trainees can reach proficiency during a program based upon a pre-defined number of scans and competency-based education may be more appropriate.

1851 Diagnostic Accuracy and Interrater Agreement of Gynecological Sonographers in Evaluating the Pouch of Douglas for Obliteration Using the Sliding Sign Technique

Study Objective Evaluate the accuracy of sonographers in classifying pouch of Douglas (POD) obliteration state and their interrater agreement with the reference standard senior sonologist. Design Prospective diagnostic accuracy and interrater agreement study. Setting Gynecology-focused ultrasound practice. Patients or Participants Seven sonographers of varying experience. Interventions Sonographer were provided with a short educational program on POD obliteration and the sliding sign technique. None were routinely utilizing the sliding sign in practice prior to study initiation. Over two months, the sonographers prospectively and consecutively performed, recorded, and interpreted the state of the POD as positive, negative or indeterminate. Senior sonologist was blinded to the sonographers’ classification when the reference standard classification was made. Measurements and Main Results Diagnostic accuracy and interrater agreement using Cohen's kappa were calculated (Table). 819 patients underwent basic TVS. The reference standard prevalence of a negative sliding sign was 43/819 (5.3%). Conclusion With a low prevalence of a negative sliding sign, it is difficult to evaluate a sonographers’ ability to correctly classify this abnormal state. However, sonographers were uniformly highly specific in their classification of the POD state. As the awareness of the sliding sign technique spreads, it will be essential to understand how to educate, credential, and monitor performance and interpretation by sonographers, who perform the majority of gynecological scans internationally.