Predicting Pouch of Douglas Obliteration Using Ultrasound and Laparoscopic Video Sets: An Interobserver and Diagnostic Accuracy Study

[Standardized acquisition and documentation of cine loops on conventional thyroid ultrasound]

Ultrasound is the basic imaging method for the assessment of the thyroid gland. Due to the high prevalence of structural disease, the examination procedure is used very frequently in Germany, in many cases in the context of follow-up. The assessment of thyroid pathologies and their dynamics is subjected to relevant inter- and intraobserver variability. Findings that were not identified during live ultrasound cannot be assessed retrospectively. Applying an SOP for the acquisition and documentation of standardized video sequences of ultrasound images (so-called cine loops), allows for a secondary retrospective evaluation of the thyroid gland, taking into account previously acquired images analogous to other cross-sectional imaging methods such as CT or MRI. The cine loops can be acquired by non-physician personnel, stored to the local PACS and used for educational and research purposes.

Clinical Significance of a Pain Scoring System for Deep Endometriosis by Pelvic Examination: Pain Score

Endometriosis-associated pain is an essential factor in deciding surgical indications of endometriosis. However, there is no quantitative method to diagnose the intensity of local pain in endometriosis (especially deep endometriosis). This study aims to examine the clinical significance of the pain score, a preoperative diagnostic scoring system for endometriotic pain that can be performed only with pelvic examination, devised for the above purpose. The data from 131 patients from a previous study were included and evaluated using the pain score. This score measures the pain intensity in each of the seven areas of the uterus and its surroundings via a pelvic examination using a numeric rating scale (NRS) which contains 10 points. The maximum value was then defined as the max pain score. This study investigated the relationship between the pain score and clinical symptoms of endometriosis or endometriotic lesions related to deep endometriosis. The preoperative max pain score was 5.93 ± 2.6, which significantly decreased to 3.08 ± 2.0 postoperatively (p = 7.70 × 10^-20). Regarding preoperative pain scores for each area, those of the uterine cervix, pouch of Douglas, and left and right uterosacral ligament areas were high (4.52, 4.04, 3.75, and 3.63, respectively). All scores decreased significantly after surgery (2.02, 1.88, 1.75, and 1.75, respectively). The correlations between the max pain score and dysmenorrhea, dyspareunia, perimenstrual dyschezia (pain with defecation), and chronic pelvic pain were 0.329, 0.453, 0.253, and 0.239, respectively, and were strongest with dyspareunia. Regarding the pain score of each area, the combination of the pain score of the pouch of Douglas area and the VAS score of dyspareunia showed the strongest correlation (0.379). The max pain score in the group with deep endometriosis (endometrial nodules) was 7.07 ± 2.4, which was significantly higher than the 4.97 ± 2.3 score obtained in the group without (p = 1.71 × 10^-6). The pain score can indicate the intensity of endometriotic pain, especially dyspareunia. A local high value of this score could suggest the presence of deep endometriosis, depicted as endometriotic nodules at that site. Therefore, this method could help develop surgical strategies for deep endometriosis.

Strengths and limitations of diagnostic tools for endometriosis and relevance in diagnostic test accuracy research

Endometriosis is a chronic systemic disease that can cause pain, infertility and reduced quality of life. Diagnosing endometriosis remains challenging, which yields diagnostic delays for patients. Research on diagnostic test accuracy in endometriosis can be difficult due to verification bias, as not all patients with endometriosis undergo definitive diagnostic testing. The purpose of this State-of-the-Art Review is to provide a comprehensive update on the strengths and limitations of the diagnostic modalities used in endometriosis and discuss the relevance of diagnostic test accuracy research pertaining to each. We performed a comprehensive literature review of the following methods: clinical assessment including history and physical examination, biomarkers, diagnostic imaging, surgical diagnosis and histopathology. Our review suggests that, although non-invasive diagnostic methods, such as clinical assessment, ultrasound and magnetic resonance imaging, do not yet qualify formally as replacement tests for surgery in diagnosing all subtypes of endometriosis, they are likely to be appropriate for advanced stages of endometriosis. We also demonstrate in our review that all methods have strengths and limitations, leading to our conclusion that there should not be a single gold-standard diagnostic method for endometriosis, but rather, multiple accepted diagnostic methods appropriate for different circumstances. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.

Vaginal ultrasound-guided Pouch of Douglas robotic entry in a live ovine model and human female cadaveric specimens

We aimed to determine whether intraoperative ultrasound is a feasible tool for visualization of the pouch of Douglas (POD) to facilitate a safe vaginal entry for direct robotic vaginal trocar insertion for pelvic floor surgery. Endovaginal ultrasound-guided needle insertion of a trocar into the POD was performed in six fresh frozen female cadavers and a live sheep animal model. Using an endovaginal probe the POD was identified as a fluid-filled space clear of bowel or adhesions, then a Veress needle was also used to confirm POD localization. Access to the POD was achieved using a robotic trocar designed for this purpose. The animal study was approved by the Ethics Committee of Asaf-Harofe hospital. Direct visualization during laparoscopy in cadavers and open cadaveric dissections confirmed safe POD entry and accurate trocar placement. This method was found feasible in the development of a safe vaginal entry in both the animal and cadaveric model, possibly negating the need for laparoscopic umbilical observation.

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

OBJECTIVES

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.

METHODS

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.

RESULTS

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.

CONCLUSIONS

Not all trainees can reach competency for TVUS evaluations of POD obliteration and bowel DE in a predefined number of scans.

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

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.

The Fresh Frozen Cadaveric Study of Direct Pouch of Douglas Laparoscopic and Robotic Trocar Insertion for Vaginal Natural Orifice Transluminal Endoscopic Surgery

STUDY OBJECTIVE

To determine the distances and angles that assure a safe entry into the pouch of Douglas (POD) during blind laparoscopic and robotic trocar entry.

DESIGN

Trocars were inserted into the POD of 4 intact fresh frozen female pelves. Cadaveric dissection was performed, and the distance from the POD to the sacrum at rest and with maximal pressure to POD with the trocar was measured. In addition, the optimal angle for trocar insertion and entry was evaluated.

SETTING

Inova Advanced Simulation and Technology Evaluation Center.

PATIENTS

Fresh frozen cadavers with intact reproductive organs.

INTERVENTIONS

Vaginal POD trocar insertion.

MEASUREMENTS AND MAIN RESULTS

Measurements were recorded from the sacrum to the POD at rest and from the sacrum to the hymen with trocar pressure. The dissection demonstrated correct trocar placement in the POD of human cadaveric specimens. The mean distances from the sacrum to the hymen, the sacrum to the POD, and the sacrum to the POD with pressure were 18.75 cm, 9.75 cm, and 7.25 cm, respectively. After the deployment of the trocar, the tip was observed to be 2 cm below the cervix in the POD. The mean trocar angle to clear the sacral promontory and the neurovascular structures without injury to the uterus was 25° to 40° from the horizontal plane and 15° to 30° from the coronal plane.

CONCLUSION

A direct trocar entry into the POD has been found to be feasible in fresh frozen cadaveric specimens. This study provided valuable information for the angle of entry into the POD to facilitate vaginal and robotic trocar entry for minimally invasive gynecologic procedures.

Imaging of gastrointestinal endometriosis: what the radiologist should know

Deep invasive gastrointestinal endometriosis (DIGIE) is a frequent and severe presentation of endometriosis. Although most cases invade the rectosigmoid colon, DIGIE can involve any portion of the gastrointestinal tract from the stomach to the rectum, and is commonly multifocal and multicentric. Although histopathologic confirmation with surgery remains the gold standard for diagnosis, ultrasound (US) and magnetic resonance imaging (MRI) are the key non-invasive imaging modalities for initial assessment. US may be preferred as a screening study because of its easy availability and low-cost. Pelvic MRI and magnetic resonance enterography (MRE) provide substantial advantages for disease mapping in the pre-operative period, particularly in extensive bowel endometriosis. Although medical management of DIGIE with hormonal therapy can help control symptoms, disease course can be relentless and require surgical intervention. Surgical options depend on, the location; length; depth; circumference; multicentric or multifocal disease. With procedures including simple excision, fulguration of superficial lesions, shaving, disc excision, and segmental resection. A successful treatment outcome is largely dependent on good communication between the treating surgeon and the radiologist, who can provide vital information for effective surgical planning by reporting the key elements that we elaborate upon in this paper.