Endorectal ultrasonography in predicting rectal wall infiltration in patients with deep pelvic endometriosis: a modern tool for an ancient disease

Malignant transformation of rectal endometriosis: Preoperative diagnosis by endorectal ultrasound guided biopsy

The prevalence of malignant transformation of endometriotic lesions is estimated between 0.3% and 1%. Malignant transformations of endometriosis occur in the colorectum is rarer, accounting for 0.25%. Because the malignant transformation of colorectal endometriosis rarely involves mucosa, it is difficult to obtain abnormal tissue by routine endoscopic biopsy. In this case, we evaluated a patient with a rectal mass by endorectal ultrasound (ERUS) and performed endorectal ultrasound-guided biopsy (EGB). Malignant transformations of endometriosis were confirmed by histological result. For patients with rectal tumors but with negative findings on colonoscopy and biopsy, ERUS and EGB contribute to preoperative diagnosis.

Advances in Imaging for Assessing Pelvic Endometriosis

In recent years, due to the development of standardized diagnostic protocols associated with an improvement in the associated technology, the diagnosis of pelvic endometriosis using imaging is becoming a reality. In particular, transvaginal ultrasound and magnetic resonance are today the two imaging techniques that can accurately identify the majority of the phenotypes of endometriosis. This review focuses not only on these most common imaging modalities but also on some additional radiological techniques that were proposed for rectosigmoid colon endometriosis, such as double-contrast barium enema, rectal endoscopic ultrasonography, multidetector computed tomography enema, computed tomography colonography and positron emission tomography-computed tomography with 16α-[18F]fluoro-17β-estradiol.

Meta-analysis and systematic review to determine the optimal imaging modality for the detection of uterosacral ligaments/torus uterinus, rectovaginal septum and vaginal deep endometriosis

STUDY QUESTION

Is there an ideal imaging modality for the detection of uterosacral ligaments/torus uterinus (USL), rectovaginal septum (RVS) and vaginal deep endometriosis (DE) in women with a clinical history of endometriosis?

SUMMARY ANSWER

The sensitivity for the detection of USL, RVS and vaginal DE using MRI seems to be better than transvaginal ultrasonography (TVS), whilst the specificity of both were excellent.

WHAT IS KNOWN ALREADY

The surgical management of women with DE can be complex and requires advanced laparoscopic skills with maximal cytoreduction being vital at the first procedure to provide the greatest symptomatic benefit. Owing to a correlation of TVS findings with surgical findings, preoperative imaging has been used to adequately consent women and plan the appropriate surgery. However, until publication of the consensus statement by the International Deep Endometriosis Analysis Group in 2016, there were significant variations within the terms and definitions used to describe DE in the pelvis.

STUDY DESIGN SIZE DURATION

A systematic review and meta-analysis was conducted using Embase, Google Scholar, Medline, PubMed and Scopus to identify studies published from inception to May 2020, of which only those from 2010 were included owing to the increased proficiency of the sonographers and advancements in technology.

PARTICIPANTS/MATERIALS SETTING METHODS

All prospective studies that preoperatively assessed any imaging modality for the detection of DE in the USL, RVS and vagina and correlated with the reference standard of surgical data were considered eligible. Study eligibility was restricted to those including a minimum of 10 unaffected and 10 affected participants.

MAIN RESULTS AND THE ROLE OF CHANCE

There were 1977 references identified from which 10 studies (n = 1188) were included in the final analysis. For the detection of USL DE, the overall pooled sensitivity and specificity for all TVS techniques were 60% (95% CI 32-82%) and 95% (95% CI 90-98%), respectively, and for all MRI techniques were 81% (95% CI 66-90%) and 83% (95% CI 62-94%), respectively. For the detection of RVS DE, the overall pooled sensitivity and specificity for all TVS techniques were 57% (95% CI 30-80%) and 100% (95% CI 92-100%), respectively. For the detection of vaginal DE, the overall pooled sensitivity and specificity for all TVS techniques were 52% (95% CI 29-74%) and 98% (95% CI 95-99%), respectively, and for all MRI techniques were 64% (95% CI 40-83%) and 98% (96% CI 93-99%). Pooled analyses were not possible for other imaging modalities.

LIMITATIONS REASONS FOR CAUTION

There was a low quality of evidence given the high risk of bias and heterogeneity in the included studies. There are also potential biases secondary to the risk of misdiagnosis at surgery owing to a lack of either histopathological findings or expertise, coupled with the surgeons not being blinded. Furthermore, the varying surgical experience and the lack of clarity regarding complete surgical clearance, thereby also contributing to the lack of histopathology, could also explain the wide range of pre-test probability of disease.

WIDER IMPLICATIONS OF THE FINDINGS

MRI outperformed TVS for the per-operative diagnosis of USL, RVS and vaginal DE with higher sensitivities, although the specificities for both were excellent. There were improved results with other imaging modalities, such as rectal endoscopy-sonography, as well as the addition of bowel preparation or ultrasound gel to either TVS or MRI, although these are based on individual studies.

STUDY FUNDING/COMPETING INTERESTS

No funding was received for this study. M.L. reports personal fees from GE Healthcare, grants from the Australian Women's and Children's Foundation, outside the submitted work. B.W.M. reports grants from NHMRC, outside the submitted work. G.C. reports personal fees from GE Healthcare, outside the submitted work; and is on the Endometriosis Advisory Board for Roche Diagnostics.

REGISTRATION NUMBER

Prospective registration with PROSPERO (CRD42017059872) was obtained.

Optimal imaging modality for detection of rectosigmoid deep endometriosis: systematic review and meta-analysis

OBJECTIVES

To review the accuracy of different imaging modalities for the detection of rectosigmoid deep endometriosis (DE) in women with clinical suspicion of endometriosis, and to determine the optimal modality.

METHODS

A search was conducted using PubMed, MEDLINE, Scopus, EMBASE and Google Scholar to identify studies using imaging to evaluate women with suspected DE, published from inception to May 2020. Studies were considered eligible if they were prospective and used any imaging modality to assess preoperatively for the presence of DE in the rectum/rectosigmoid, which was then correlated with the surgical diagnosis as the reference standard. Eligibility was restricted to studies including at least 10 affected and 10 unaffected women. The QUADAS-2 tool was used to assess the quality of the included studies. Mixed-effects diagnostic meta-analysis was used to determine the overall pooled sensitivity and specificity of each imaging modality for rectal/rectosigmoid DE, which were used to calculate the likelihood ratio of a positive (LR+) and negative (LR-) test and diagnostic odds ratio (DOR).

RESULTS

Of the 1979 records identified, 30 studies (3374 women) were included in the analysis. The overall pooled sensitivity and specificity, LR+, LR- and DOR for the detection of rectal/rectosigmoid DE using transvaginal sonography (TVS) were, respectively, 89% (95% CI, 83-92%), 97% (95% CI, 95-98%), 30.8 (95% CI, 17.6-54.1), 0.12 (95% CI, 0.08-0.17) and 264 (95% CI, 113-614). For magnetic resonance imaging (MRI), the respective values were 86% (95% CI, 79-91%), 96% (95% CI, 94-97%), 21.0 (95% CI, 13.4-33.1), 0.15 (95% CI, 0.09-0.23) and 144 (95% CI, 70-297). For computed tomography, the respective values were 93% (95% CI, 84-97%), 95% (95% CI, 81-99%), 20.3 (95% CI, 4.3-94.9), 0.07 (95% CI, 0.03-0.19) and 280 (95% CI, 28-2826). For rectal endoscopic sonography (RES), the respective values were 92% (95% CI, 87-95%), 98% (95% CI, 96-99%), 37.1 (95% CI, 21.1-65.4), 0.08 (95% CI, 0.05-0.14) and 455 (95% CI, 196-1054). There was significant heterogeneity and the studies were considered methodologically poor according to the QUADAS-2 tool.

CONCLUSIONS

The sensitivity of TVS for the detection of rectal/rectosigmoid DE seems to be slightly better than that of MRI, although RES was superior to both. The specificity of both TVS and MRI was excellent. As TVS is simpler, faster and more readily available than the other methods, we believe that it should be the first-line diagnostic tool for women with suspected DE. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.

Meta-analysis and systematic review to determine the optimal imaging modality for the detection of bladder deep endometriosis

OBJECTIVE

To review the diagnostic accuracy and determine the optimum imaging modality for the detection of bladder deep endometriosis (DE) in women with a clinical suspicion of endometriosis.

METHODS

A systematic review of studies published from inception to May 2020 using Embase, Google Scholar, Medline, PubMed and Scopus. Prospective studies, which pre-operatively assessed any imaging modality for the presence of bladder DE, and correlated with the gold standard surgical data as a reference were included. The QUADAS-2 tool was used to assess quality. This review was prospectively registered with PROSPERO (CRD42017059872).

RESULTS

Of the 1,977 references identified, 8 studies (n = 1,052) were included in the analysis. The overall pooled sensitivity and specificity, from which the likelihood ratio of a positive test (LR+), likelihood ratio of a negative test (LR-) and diagnostic odds ratio (DOR) were calculated, for all transvaginal ultrasonography (TVS) techniques were 55 % (95 % CI 28-79%), 99 % (95 % CI 98-100%), 54.5 (95 % CI 18.9-157.4), 0.46 (95 % CI 0.25 - 0.85) and 119 (95 % CI 24-577), and for only two-dimensional (2D) TVS 53 % (95 % CI 23-82%), 99 % (96 % CI 97-100%), 48.8 (95 % CI 13.1-181.4), 0.47 (95 % CI 0.23 - 0.98), and 104 (95 % CI 15-711), respectively. Meta-analyses of the other modalities, namely magnetic resonance imaging (MRI) and transrectal endoscopic sonography (RES), were not possible due to the limited number of studies. There was significant heterogeneity and the studies were considered poor methodologically according to the QUADAS-2 tool.

CONCLUSIONS

Whilst the sensitivity of TVS was limited, the specificity was excellent. Given that there is a paucity of literature for other imaging modalities, until more studies are performed, TVS should be considered as the first-line tool given it is the only modality with sufficient evidence.

Other imaging techniques: Double-contrast barium enema, endoscopic ultrasonography, multidetector CT enema, and computed tomography colonoscopy

Double-contrast barium enema (DCBE), transrectal endoscopic ultrasonography (REU), multidetector computerized tomography enema (MDCT-e), and computed tomography colonoscopy (CTC) have been successfully used for the diagnosis of bowel endometriosis. DCBE provides a complete overview of the entire colon and allows detecting cecal nodules. The accuracy of DCBE is operator dependent and, thus, it may have low specificity. It does not allow identifying the cause of the mass effect. DCBE requires the administration of barium and exposure to radiation. REU precisely estimates the distance between the rectosigmoid nodule and the anal verge. However, it allows investigating only the distal part of rectosigmoid, it misses anterior pelvic lesions, and it has poor sensitivity for the diagnosis of endometriomas. MDCT-e is accurate and reproducible in diagnosing intestinal endometriosis and in assessing its characteristics: the largest diameter of the nodule, the distance between the distal part of the nodule and the anal verge, and depth of infiltration of endometriosis in the intestinal wall. MDCT-e requires the administration of iodinated contrast medium (CM) and the exposure to radiations. CTC has good performance in the diagnosis of rectosigmoid endometriosis. It allows estimating the degree of intestinal stenosis CTC, and the distance between the intestinal endometriotic nodule and the anal verge. It requires exposure to radiations, and it may require the administration of an iodinated CM.

Is training sufficient for ultrasound operators to diagnose deep infiltrating endometriosis and bowel involvement by transvaginal ultrasound?

OBJECTIVES

To assess and compare the diagnostic accuracy of transvaginal ultrasonography (TVUS) by trained or untrained ultrasound operators in deep infiltrating endometriosis (DIE) imaging, for diagnosing DIE and bowel involvement.

METHODS

This was an observational study of patients with clinically suspected DIE operated in a reference center. TVUS was performed pre-operatively by a trained or/and untrained ultrasound operator to search for DIE and rectal involvement. During surgery, DIE was diagnosed according to macroscopic and histological criteria. Sensitivity (Se), specificity (Sp) and c-index were calculated with 95% confidence intervals for trained and untrained operators, if TVUS results were significantly predictive of DIE and rectal involvement at p<0.05.

RESULTS

115 patients were included: 100 (87%) had DIE and 34 (29.6%) had bowel involvement. TVUS was performed by a trained ultrasound operator for 70 patients and by an untrained one for 56 patients. When performed by a trained operator, TVUS significantly predicted DIE with a Se of 58% (95% CI, 46-70), a Sp of 87.5% (95% CI, 63-100) and a c-index of 0.73 (95% CI, 0.59-0.87). TVUS performed by an untrained operator was not significantly predictive of DIE (p=0.58). Rectal involvement was significantly predicted by TVUS performed by a trained operator with a Se of 40% (95% CI, 23-59), a Sp of 93% (95% CI, 86-100) and a c-index of 0.67 (95% CI, 0.56-0.77). None of the untrained ultrasound operators diagnosed a bowel involvement.

CONCLUSION

TVUS is not sufficient to diagnose DIE and bowel involvement, in particular when performed by untrained ultrasound operators.

Diagnosis of Bowel Endometriosis: A Review

Since the presence of intestinal endometriosis cannot be reliably established by physical examination or the evaluation of intestinal symptoms, imaging techniques are required for the diagnosis of bowel endometriosis. This review evaluates the techniques available for the diagnosis of intestinal endometriosis based on a search of the Medline database and Embase up to February 2010. Several studies have proved that radiological techniques (double contrast barium enema, magnetic resonance imaging, and multidetector computerized tomography enteroclysis) are able to accurately diagnose intestinal endometriosis. Magnetic resonance imaging has the advantage of determining the presence of deep endometriotic lesions in other pelvic locations. Rectal endoscopic ultrasonography can precisely determine the presence of bowel endometriosis but its use is limited by the availability of the equipment required to carry out the exam. Over the last five years, several studies have proved that transvaginal ultrasonography is accurate in the diagnosis of rectosigmoid endometriosis; in addition, this exam is well tolerated by patients and is inexpensive. Therefore, transvaginal ultrasonography should be the first-line investigation in patients with suspected intestinal endometriosis.

Imaging modalities for the non-invasive diagnosis of endometriosis

BACKGROUND

About 10% of women of reproductive age suffer from endometriosis. Endometriosis is a costly chronic disease that causes pelvic pain and subfertility. Laparoscopy, the gold standard diagnostic test for endometriosis, is expensive and carries surgical risks. Currently, no non-invasive tests that can be used to accurately diagnose endometriosis are available in clinical practice. This is the first review of diagnostic test accuracy of imaging tests for endometriosis that uses Cochrane methods to provide an update on the rapidly expanding literature in this field.

OBJECTIVES

• To provide estimates of the diagnostic accuracy of imaging modalities for the diagnosis of pelvic endometriosis, ovarian endometriosis and deeply infiltrating endometriosis (DIE) versus surgical diagnosis as a reference standard.• To describe performance of imaging tests for mapping of deep endometriotic lesions in the pelvis at specific anatomical sites.Imaging tests were evaluated as replacement tests for diagnostic surgery and as triage tests that would assist decision making regarding diagnostic surgery for endometriosis.

SEARCH METHODS

We searched the following databases to 20 April 2015: MEDLINE, CENTRAL, EMBASE, CINAHL, PsycINFO, Web of Science, LILACS, OAIster, TRIP, ClinicalTrials.gov, MEDION, DARE, and PubMed. Searches were not restricted to a particular study design or language nor to specific publication dates. The search strategy incorporated words in the title, abstracts, text words across the record and medical subject headings (MeSH).

SELECTION CRITERIA

We considered published peer-reviewed cross-sectional studies and randomised controlled trials of any size that included prospectively recruited women of reproductive age suspected of having one or more of the following target conditions: endometrioma, pelvic endometriosis, DIE or endometriotic lesions at specific intrapelvic anatomical locations. We included studies that compared the diagnostic test accuracy of one or more imaging modalities versus findings of surgical visualisation of endometriotic lesions.

DATA COLLECTION AND ANALYSIS

Two review authors independently collected and performed a quality assessment of data from each study. For each imaging test, data were classified as positive or negative for surgical detection of endometriosis, and sensitivity and specificity estimates were calculated. If two or more tests were evaluated in the same cohort, each was considered as a separate data set. We used the bivariate model to obtain pooled estimates of sensitivity and specificity when sufficient data sets were available. Predetermined criteria for a clinically useful imaging test to replace diagnostic surgery included sensitivity ≥ 94% and specificity ≥ 79%. Criteria for triage tests were set at sensitivity ≥ 95% and specificity ≥ 50%, ruling out the diagnosis with a negative result (SnNout test - if sensitivity is high, a negative test rules out pathology) or at sensitivity ≥ 50% with specificity ≥ 95%, ruling in the diagnosis with a positive result (SpPin test - if specificity is high, a positive test rules in pathology).

MAIN RESULTS

We included 49 studies involving 4807 women: 13 studies evaluated pelvic endometriosis, 10 endometriomas and 15 DIE, and 33 studies addressed endometriosis at specific anatomical sites. Most studies were of poor methodological quality. The most studied modalities were transvaginal ultrasound (TVUS) and magnetic resonance imaging (MRI), with outcome measures commonly demonstrating diversity in diagnostic estimates; however, sources of heterogeneity could not be reliably determined. No imaging test met the criteria for a replacement or triage test for detecting pelvic endometriosis, albeit TVUS approached the criteria for a SpPin triage test. For endometrioma, TVUS (eight studies, 765 participants; sensitivity 0.93 (95% confidence interval (CI) 0.87, 0.99), specificity 0.96 (95% CI 0.92, 0.99)) qualified as a SpPin triage test and approached the criteria for a replacement and SnNout triage test, whereas MRI (three studies, 179 participants; sensitivity 0.95 (95% CI 0.90, 1.00), specificity 0.91 (95% CI 0.86, 0.97)) met the criteria for a replacement and SnNout triage test and approached the criteria for a SpPin test. For DIE, TVUS (nine studies, 12 data sets, 934 participants; sensitivity 0.79 (95% CI 0.69, 0.89) and specificity 0.94 (95% CI 0.88, 1.00)) approached the criteria for a SpPin triage test, and MRI (six studies, seven data sets, 266 participants; sensitivity 0.94 (95% CI 0.90, 0.97), specificity 0.77 (95% CI 0.44, 1.00)) approached the criteria for a replacement and SnNout triage test. Other imaging tests assessed in small individual studies could not be statistically evaluated.TVUS met the criteria for a SpPin triage test in mapping DIE to uterosacral ligaments, rectovaginal septum, vaginal wall, pouch of Douglas (POD) and rectosigmoid. MRI met the criteria for a SpPin triage test for POD and vaginal and rectosigmoid endometriosis. Transrectal ultrasonography (TRUS) might qualify as a SpPin triage test for rectosigmoid involvement but could not be adequately assessed for other anatomical sites because heterogeneous data were scant. Multi-detector computerised tomography enema (MDCT-e) displayed the highest diagnostic performance for rectosigmoid and other bowel endometriosis and met the criteria for both SpPin and SnNout triage tests, but studies were too few to provide meaningful results.Diagnostic accuracies were higher for TVUS with bowel preparation (TVUS-BP) and rectal water contrast (RWC-TVS) and for 3.0TMRI than for conventional methods, although the paucity of studies precluded statistical evaluation.

AUTHORS' CONCLUSIONS

None of the evaluated imaging modalities were able to detect overall pelvic endometriosis with enough accuracy that they would be suggested to replace surgery. Specifically for endometrioma, TVUS qualified as a SpPin triage test. MRI displayed sufficient accuracy to suggest utility as a replacement test, but the data were too scant to permit meaningful conclusions. TVUS could be used clinically to identify additional anatomical sites of DIE compared with MRI, thus facilitating preoperative planning. Rectosigmoid endometriosis was the only site that could be accurately mapped by using TVUS, TRUS, MRI or MDCT-e. Studies evaluating recent advances in imaging modalities such as TVUS-BP, RWC-TVS, 3.0TMRI and MDCT-e were observed to have high diagnostic accuracies but were too few to allow prudent evaluation of their diagnostic role. In view of the low quality of most of the included studies, the findings of this review should be interpreted with caution. Future well-designed diagnostic studies undertaken to compare imaging tests for diagnostic test accuracy and costs are recommended.

Transrectal ultrasound - Techniques and outcomes in the management of intestinal endometriosis

The widespread use of endoscopic ultrasound has facilitated the evaluation of subepithelial and surrounding lesions of the gastrointestinal tract. Deep pelvic endometriosis, with or without infiltration of the intestinal wall, is a frequent disease that can be observed in women in their fertile age. Patients of this disease may present nonspecific signs and symptoms or be completely asymptomatic. Laparoscopic surgical resection of endometriotic lesions is the treatment of choice in symptomatic patients. An accurate preoperative evaluation is indispensable for therapeutic decisions mainly in the suspicion of intestinal wall and/or urinary tract infiltration, and also in cases where we need to establish histological diagnosis or to rule out malignant disease. Diagnostic tools, including transrectal ultrasound, magnetic resonance image, transvaginal ultrasound, barium enema, and colonoscopy, play significant roles in determining the presence, depth, histology, and other relevant data about the extension of the disease. Diagnostic algorithm depends on the clinical presentation, the expertise of the medical team, and the technology available at each institution. This article reviews and discusses relevant clinical points in endometriosis, including techniques and outcomes of the study of the disease through transrectal ultrasound and fine-needle aspiration.

Endometriosis and Chronic Pelvic Pain: Unraveling the Mystery Behind this Complex Condition

Nurses often encounter patients with chronic pelvic pain associated with endometriosis, which is a puzzling and problematic gynecologic condition that has continued to plague women and baffle doctors and researchers worldwide since it was first identified by Dr. J. Sampson in the 1920s (Sampson, 1940 ). Endometriosis is defined as the growth, adhesion and progression of endometrial glands and stroma outside of the uterine cavity, with cellular activity evident in lesions, nodules, cysts or endometriomas (Audebert et al., 1992 ). Although it typically appears benign on histopathology, endometriosis has been likened to a malignant tumor since the lesions grow, infiltrate and adhere to adjacent tissues and interfere with physiologic processes (Kitawaki et al., 2002 ; Noble, Simpson, Johns, & Bulun, 1996 ). Ectopic endometriotic growths respond to cyclic changes of estrogen and proliferate and shed in a manner similar to eutopic endometrium. This cyclic ectopic activity results in internal bleeding, formation of scar tissue, inflammation and sometimes debilitating chronic pain (Kitawaki et al.).

Bowel endometriosis: presentation, diagnosis, and treatment

Bowel endometriosis opens a new frontier for the gynecologist, as it forces the understanding of a new anatomy, a new physiology, and a new pathology. Although some women with bowel endometriosis may be asymptomatic, the majority of them develop a variety of gastrointestinal complains. No clear guideline exists for the evaluation of patients with suspected bowel endometriosis. Given the fact that, besides rectal nodules, bowel endometriosis can not be diagnosed by physical examination, imaging techniques should be used. Several techniques have been proposed for the diagnosis of bowel endometriosis including double-contrast barium enema, transvaginal ultrasonography, rectal endoscopic ultrasonography, magnetic resonance imaging, and multislice computed tomography enteroclysis. Medical management of bowel endometriosis is currently speculative; expectant management should be carefully balanced with the severity of symptoms and the feasibility of prolonged follow-up. Several studies demonstrated an improvement in quality of life after extensive surgical excision of the disease. Bowel endometriotic nodules can be removed by various techniques: mucosal skinning, nodulectomy, full thickness disc resection, and segmental resection. Although the indications for colorectal resection are controversial, recent data suggest that aggressive surgery improves symptoms and quality of life.

TARGET AUDIENCE

Obstetricians & Gynecologists, Family Physicians.

LEARNING OBJECTIVES

After completion of this article, the reader should be able to describe the varied appearance of bowel endometriosis, recall that it is difficult to diagnose preoperatively, and explain that surgical treatment offers the best treatment in symptomatic patients through a variety of surgical techniques which is best accomplished with a team approach.

[Endometriosis imaging]

Pelvic endometriosis primarily affects the ovaries, pelvic peritoneum, utero-sacral ligaments, Douglas pouch, vagina, rectum and bladder. Clinical assessment is difficult, and imaging proves necessary to determine location and extent of the disease. We review pelvic endometriosis with regards to imaging modalities: technical considerations, imaging patterns, diagnostic performance and respective place of ultrasound and MRI.