Three-Dimensional Ultrasound in the Management of Bladder 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.

Accuracy of transvaginal ultrasound and magnetic resonance imaging for diagnosis of deep endometriosis in bladder and ureter: a meta-analysis

This meta-analysis aimed to determine the accuracy of transvaginal ultrasound (TVS) and pelvic magnetic resonance imaging (MRI) in diagnosing urinary tract endometriosis (UTE). A comprehensive search of the Pubmed and Embase was conducted between January 1989 and June 2020. Studies that described the accuracy of MRI or TVS for the diagnosis of UTE using surgical data as the reference standard were included. Of the 913 citations identified, 23 studies were analysed. For detection of endometriosis in bladder endometriosis (BE), the overall pooled sensitivities of TVS and MRI were 72% and 68% respectively, and their specificities were 99% and 100% respectively. For detection of endometriosis in the ureteral endometriosis (UE), the overall pooled sensitivities of TVS and MRI were 97% and 87% respectively, and their specificities were both 100%. In conclusion, both TVS and MRI provide good accuracy with specific strong points in diagnosing UTE and seem useful first-line methods from a clinical perspective. Besides, pelvic MRI and TVS are more accurate for predicting UTE localised in the ureter than bladder, especially in terms of sensitivity.IMPACT STATEMENTWhat is already known on this subject? Previous studies have confirmed high diagnostic value of transvaginal ultrasound (TVS) and magnetic resonance imaging (MRI) on bladder endometriosis (BE) respectively. However, high heterogeneity was found for both sensitivity and specificity and no meta-analysis has yet been performed to test the diagnostic value of TVS and MRI for ureteral endometriosis (UE).What the results of this study add? In this meta-analysis, we firstly confirmed high diagnostic value of TVS and MRI on UE respectively. For detection of UE, the overall pooled sensitivities of TVS and MRI were 97% and 87% respectively, and their specificities were both 100%.What the implications are of these findings for clinical practice and/or further research? Early preoperative diagnosis and accurate understanding of the widespread distribution of endometriosis are prerequisites for radical surgical in UTE. In the present study, we updated the previous results on the accuracy of TVS and MRI for the diagnosis of BE and firstly confirmed high diagnostic value of TVS and MRI on UE. Both TVS and MRI provide good accuracy with specific strong points in diagnosing UTE and seem useful first-line methods from a clinical perspective.

Accuracy of Transvaginal Ultrasound Compared to Cystoscopy in the Diagnosis of Bladder Endometriosis Nodules

OBJECTIVES

To evaluate the accuracy of transvaginal ultrasound (TVUS) in predicting detrusor infiltration and ureteral meatus involvement in patients with bladder endometriosis (BE) to select which cystoscopic procedures could be avoided and, secondarily, to assess the relationship between symptoms and the characteristics of nodules and the association of BE with other forms of endometriosis.

METHODS

Patients with BE diagnosed by TVUS were classified according to detrusor infiltration: BE with partial involvement of the muscular layer (group 1) and total muscular layer involvement with bladder protrusion (group 2). We analyzed the accuracy of TVUS compared with subsequently performed cystoscopy, the correlation with symptoms, and the association with other forms of endometriosis.

RESULTS

Among the 22 patients included, TVUS showed 9 patients with BE nodules partially affecting the detrusor (group 1) with normal cystoscopic findings (TVUS negative predictive value, 100%). Transvaginal ultrasound detected 13 nodules with total involvement, all visible by cystoscopy (TVUS positive predictive value, 100%). Transvaginal ultrasound also identified ureteral orifices that were free of involvement at greater than 10 mm from the BE nodule in 21 of 22 women (TVUS sensitivity, 95%). Ultrasound criteria for adenomyosis and endometriosis in other locations were present in 20 of 22 patients.

CONCLUSIONS

Transvaginal ultrasound can identify the infiltration of BE nodules in the bladder wall and predict cystoscopic findings with great accuracy. Nodules that partially affect the muscular layer have normal cystoscopic findings, thereby obviating the need for this procedure. Bladder endometriosis nodules are commonly associated with other forms of endometriosis and do not usually affect the ureteral meatus.

Ultrasonographic 3D Evaluation in the Diagnosis of Bladder Endometriosis: A Prospective Comparative Diagnostic Accuracy Study

OBJECTIVE

The use of three-dimensional (3D) transvaginal ultrasonography (TVS) has been investigated for the diagnosis of deep endometriosis (DE). This study aimed to evaluate if 3D reconstructions improve the performance of TVS) in assessing the presence and characteristics of bladder endometriosis (BE).

DESIGN

This was a single-center comparative diagnostic accuracy study. Participants/Materials, Setting, Methods: Patients referred to our institution (Piazza della Vittoria 14 Srl, Genova, Italy) with clinical suspicion of DE were included. In case of surgery, women underwent systematic preoperative ultrasonographic imaging; an experienced sonographer performed a conventional TVS; another experienced sonographer, blinded to results of the previous exam, performed TVS, with the addition of 3D modality. The presence and characteristics of BE nodules were described in accord with International DE Analysis group consensus. Ultrasound data were compared with surgical and histological results.

RESULTS

Overall, BE was intraoperatively found in 34 out of 194 women who underwent surgery for DE (17.5%; 95% confidence interval: 12.8-23.5%). TVS without and with 3D reconstructions were able to detect endometriotic BE in 82.2% (n = 28/34) and 85.3% (n = 29/34) of the cases (p = 0.125). Both the exams similarly estimated the largest diameter of BE (p = 0.652) and the distance between the endometriotic nodule and the closest ureteral meatus (p = 0.341). However, TVS with 3D reconstructions was more precise in estimating the volume of BE (p = 0.031). In one case (2.9%), TVS without and with 3D reconstructions detected the infiltration of the intramural ureter, which was confirmed at surgery and required laparoscopic ureterovesical reimplantation.

LIMITATIONS

The extensive experience of the gynecologists performing the ultrasonographic scans, the lack of prestudy power analysis, and the population selected, which may have been influenced by the position of the institution as a referral center specialized in the treatment of severe endometriosis, are limitations of the current study.

CONCLUSION

Our results demonstrated the high accuracy of ultrasound for diagnosing BE. The addition of 3D reconstructions does not improve the performance of TVS in diagnosing the presence and characteristics of BE. However, the volume of BE may be more precisely assessed by 3D ultrasound.

Bladder endometriosis: Preoperative MRI analysis with assessment of extension to ureteral orifices

PURPOSE

The purpose of this study was to retrospectively evaluate the performance of magnetic resonance imaging (MRI) in locating endometriosis implants within the bladder wall with assessment of ureteral orifice extension using surgical findings as standard of reference.

MATERIALS AND METHODS

MRI examinations of 39 consecutive women (mean age: 31.2±5.5 [SD] years; age range: 22-42years) operated in 3 university hospitals for bladder endometriosis over a 6-year period were reviewed by 2 independent readers. Interobserver agreement was assessed using Kappa tests. Results of consensus reading were used to calculate sensitivity, specificity and accuracy of MRI for the diagnosis, location and extent of endometriosis implants using surgical findings as the standard of reference.

RESULTS

Mean bladder repletion volume was 134±110 [SD] mL (range: 21-479mL). The mean largest endometriosis implant diameter was 30±7 [SD] mm (range: 19-41mm). On MR images, 34/39 (87%) endometriosis implants were present in the two anterior thirds of the dome (k=0.45), 31/39 (79%) extended or were present in the posterior third pouch (k=0.92) and 25/39 (64%) extended into the bladder base (k=0.84) with sensitivities of 100% (31/31; 95% confidence interval [CI]: 89-100%), 100% (30/30; 95% CI: 88-100%) and 90% (19/21; 95% CI: 69-98%), respectively, specificities of 83% (5/6, 95% CI: 36-100), 88% (7/8, 95% CI: 47-100%), 87% (13/15; 95% CI: 52-96), respectively and accuracies of 97% (36/37, 95% CI: 86-100%), 97% (37/38; 95% CI: 86-100%), and 89% (32/36; 95% CI: 74-97%), respectively. In 9 (9/25; 36%) patients with bladder base involvement, a zero distance was reported between endometriosis implants and ureteral orifices, all but one presenting with low-to-moderate bladder volumes. In the two patients who needed ureteral resection-reimplantation, ureteral dilation was associated with a zero distance. External adenomyosis was reported in 26/39 (66%) patients (k=0.94).

CONCLUSION

A dedicated preoperative MRI work-up for bladder endometriosis helps accurately depict and locate endometriosis implants. Adequate bladder filling is needed to improve appropriate estimate of the distance between endometriosis implants and ureteral orifices to better predict requirement of ureteral resection-reimplantation.

Ultrasound Differential Diagnosis in Deep Infiltrating Endometriosis of the Urinary Tract

Endometriosis of the urinary tract is a rare condition that may lead to severe complications. At present, the major challenge appears to be the ultrasound differential diagnosis with diseases that can afflict the ureter and the bladder. Preoperative scan findings were compared with surgical and histologic records. Twenty-three cases were selected as being of interest, as they were referred for suspected endometriosis, whereas second-level ultrasound revealed a different disease in some cases. This case series aims to help in becoming familiar with the possible differential diagnosis of lesions of the urinary tract that resemble endometriosis.

Virtual cystoscopy and colonoscopy to assess deep infiltrating endometriosis

Introduction:

Faced with a suspicion of endometriosis, transvaginal sonography is the first-line procedure to diagnose deep infiltrating endometriosis.

Methods:

We recently introduced the FlyThru® mode from TOSHIBA aplio 500. With the 3D acquisition (Multiplanar Reconstruction), we can assess the deep invasion of the endometriosis nodule into the digestive and bladder wall and provide a virtual colonoscopy or cystoscopy. The entire wall of the organ can be explored either by starting the animation or by rotating the arrow. The detection threshold can be adjusted manually from 45 to 100 in order to remove any artifacts.

Results:

We reported two deep infiltrating endometriosis nodules explored with FlyThru mode: the first one in the rectum and the second in the bladder. Similar to a colonoscopy, the virtual animation of the FlyThru mode showed the progression into the intestine lumen until the visualization of the bulge of the nodule. Operators can appreciate precisely the location, the degree of stenosis, and the circumferential involvement of the bowel wall. The bulges of the two nodules were also visible into the bladder. The size of the lesions was assessed and related to bladder volume, which represents important preoperative data.

Conclusion:

Three dimensional-transvaginal sonography combined with the FlyThru mode allows the enhanced practitioner to diagnose and assess the invasion of an endometriosis nodule in a single procedure.

Deep Infiltrating Endometriosis: Comparison Between 2-Dimensional Ultrasonography (US), 3-Dimensional US, and Magnetic Resonance Imaging

OBJECTIVES

To evaluate the diagnostic accuracy of 2-dimensional (2D) and 3-dimensional (3D) transvaginal ultrasonography (US) in comparison with magnetic resonance imaging (MRI) for identification of deep infiltrating endometriosis.

METHODS

In this prospective observational study, 159 premenopausal women who underwent surgery for a clinical suspicion of deep infiltrating endometriosis were prospectively enrolled. All women underwent 2DUS, 3DUS, and MRI. The following 3 locations of deep endometriosis were considered: (1) intestinal; (2) other posterior lesions (retrocervical septum, rectovaginal septum, uterosacral ligaments, and vaginal fornix); and (3) anterior. The sensitivity, specificity, positive predictive value, and negative predictive value of 2D and 3D transvaginal US in comparison with MRI were determined.

RESULTS

Intestinal deep infiltrating endometriosis was identified by 2DUS in 56 of 66 patients, by 3DUS in 59 of 66, and by MRI in 61 of 66. A receiver operating characteristic curve analysis showed optimal results for 2DUS, 3DUS, and MRI (areas under the curve, 0.86, 0.915, and 0.935, respectively) with a statistically significant difference between 2DUS and MRI (P = .0103), even when the 95% confidence interval showed an overlap. Other posterior deep infiltrating endometriosis was identified by 2DUS in 55 of 75 patients, by 3DUS in 65 of 75, and by MRI in 66 of 75. A receiver operating characteristic curve analysis showed very good results for 2DUS, 3DUS, and MRI (areas under the curve, 0.801, 0.838, and 0.857) with no statistically significant differences. In the 12 women with deep infiltrating endometriosis in the anterior location, the nodules were correctly identified by 2DUS in 3 of 12 patients, by 3DUS in 5 of 12, and by MRI in 6 of 12.

CONCLUSIONS

Our results seem to suggest that there is a statistically significant difference between 2DUS and MRI for the intestinal location of deep infiltrating endometriosis, whereas no differences were found among the techniques for the other locations.

[Performances and place of sonography in the diagnostic of endometriosis: CNGOF-HAS Endometriosis Guidelines]

Endometriosis is difficult to diagnose clinically. Transvaginal sonography (TVS) is a procedure that is known to be operator-dependent, which mean that published evidences has to be balanced with the level of the sonographer that produced the data. The objective of this publication was to assess the performances of the sonography in the diagnosis of endometriosis in order to establish the French national recommendations. We searched the MEDLINE database for publication from January 2000 to September 2017 using keywords associated with endometriosis and sonography. Eighty-four trial and reviews published in English or French were included. Ovarian endometrioma can usually be diagnosed by a non-expert sonographer, especially when its aspect is typical. In case of an ovarian cyst with atypical presentation, it is recommended to control the sonography by a referent or to perform an MRI. In menopaused women, any ovarian cyst should be considered as a cancer until proven otherwise. In the diagnosis of posterior deep invasive endometriosis (DIE), TVS with sensitivity and specificity of 96 and 99% respectively, seems at least equivalent if not superior to MRI. However, these performances are related to expert sonographers. To reach sufficient efficiency in posterior DIE, the estimated learning curve for a sonographer is 44 cases. When posterior DIE is suspected, we recommend proposing a TVS "performed by an expert" or a MRI "at least interpreted by an expert". In anterior DIE, TVS has a good specificity (100%), but its sensitivity is poor in the literature (64%). TVS is therefore not able to eliminate the diagnosis. However a renal ultrasound should be proposed each time a urinary endometriosis is confirmed, and should be considered whenever posterior DIE is diagnosed especially the lesion is superior to 3cm.

Techniques in minimally invasive surgery for advanced endometriosis

PURPOSE OF REVIEW

Surgery can be an important treatment option for women with symptomatic endometriosis. This review summarizes the recommended preoperative work up and techniques in minimally invasive surgery for treatment of deeply infiltrating endometriosis (DIE) involving the obliterated posterior cul-de-sac, bowel, urinary tract, and extrapelvic locations.

RECENT FINDINGS

Surgical management of DIE can pose a challenge to the gynecologic surgeon given that an extensive dissection is usually necessary. Given the high risk of recurrence, it is vital that an adequate excision is performed. With improved imaging modalities, preoperative counseling and surgical planning can be optimized. It is essential to execute meticulous surgical technique and include a multidisciplinary surgical team when indicated for optimal results.

SUMMARY

Advanced laparoscopic skills are often necessary to completely excise DIE. A thorough preoperative work up is essential to provide correct patient counseling and incorporation of the preferred surgical team to decrease complications and optimize surgical outcomes. Surgical management of endometriosis is aimed at ameliorating symptoms and preventing recurrence.

Three-Dimensional Computerized Model Based on the Sonourethrogram: A Novel Technique to Evaluate Anterior Urethral Stricture

PURPOSE

The sonourethrogram is a useful alternative to the traditional retrograde urethrogram to evaluate anterior urethral strictures. With the development of 3-dimensional reconstructive techniques 3-dimensional urethral imaging can provide more accurate and useful information to enable the surgeon to make the best surgical decisions. We evaluated the accuracy and efficacy of a 3-dimensional reconstructed digital model of the urethra based on the sonourethrogram to assess anterior urethral disease.

MATERIALS AND METHODS

A total of 50 patients with an anterior urethral stricture and 10 healthy volunteers were enrolled in this study from April 2014 to January 2017. All patients and volunteers underwent sonourethrogram and retrograde urethrogram. Three-dimensional urethral models were reconstructed based on the sonourethrogram. Stricture length and location on retrograde urethrogram or sonourethrogram based images were compared with those found at operation.

RESULTS

The 3-dimensional digital model revealed the entire anterior urethra, including the navicular fossa, and the penile and bulbar parts. The semitransparent model clearly demonstrated the structure of the corpus spongiosum and inside the urethral lumen. Further information on spongiofibrosis could also be seen in the 3-dimensional digital model. There was no significant difference in stricture length or location in the 3-dimensional model compared with retrograde urethrogram imaging and actual surgical findings. However, the latest technique could only reconstruct the short segment of the anterior urethra due to the probe width limitation.

CONCLUSIONS

The 3-dimensional computerized model based on the sonourethrogram is a novel and effective technique of evaluating anterior urethral strictures.

Bladder Endometriosis: A Systematic Review of Pathogenesis, Diagnosis, Treatment, Impact on Fertility, and Risk of Malignant Transformation

CONTEXT

The bladder is the most common site affected in urinary tract endometriosis. There is controversy regarding the pathogenesis, clinical management (diagnosis and treatment), impact on fertility, and risk of malignant transformation of bladder endometriosis (BE).

OBJECTIVE

To systematically evaluate evidence regarding the pathogenesis, diagnosis, medical and surgical treatment, impact on female fertility, and risk of malignant transformation of BE.

EVIDENCE ACQUISITION

A systematic review of PubMed/Medline from inception until October 2016 was performed in accordance with the Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) statement and was registered in the PROSPERO registry (www.crd.york.ac.uk/prospero; CRD42016039281). Eighty-seven articles were selected for inclusion in this analysis.

EVIDENCE SYNTHESIS

BE is defined as the presence of endometrial glands and stroma in the detrusor muscle. Ultrasonography is the first-line technique for assessment of BE owing to its accuracy, safety, and cost. Clinical management can be conservative, using hormonal therapies, or surgical. When conservative treatment is preferred, estrogen-progestogen combinations and progestogens should be chosen because of their favorable profile that allows long-term therapy. Surgery should guarantee complete removal of the bladder nodule to minimize recurrence, so transurethral surgery alone should be avoided in favor of segmental bladder resection. There is not a strong rationale for hypothesizing a detrimental impact of BE per se on fertility. Furthermore, current evidence does not support the removal of bladder endometriotic lesions because of the potential risk of malignant transformation since this phenomenon is exceedingly rare.

CONCLUSIONS

BE is a challenging condition, and the common coexistence of other types of endometriosis means that clinical management of BE should involve collaboration between gynecologists and urologists.

PATIENT SUMMARY

In this article we review available knowledge on bladder endometriosis. The review provides a useful tool to guide physicians in the management of this complex condition.

[Pictures balance for optimal surgical management of pelvic endometriosis. Imaging and surgery of endometriosis]

Endometriosis is a frequent benign pathology that is found in 10-15% of women and in 20% of infertile women. It has an impact on fertility, but also in everyday life. If medical treatment fails, surgical treatment can be offered to the patient. To provide adequate treatment and give clearer information to patients, it seems essential to achieve an optimal preoperative imaging assessment. Thus, the aim of this work is to define the information expected by the surgeon and the indications of each imaging test for each compartment of the pelvis, allowing an ideal surgical management of pelvic endometriosis. We will not discuss imaging techniques' principles and we will not develop the indications and surgical techniques.