Intra- and interobserver variability in nodule size of rectosigmoid endometriosis measured by two- and three-dimensional transvaginal sonography

Sonomorphologic Changes in Colorectal Deep Endometriosis: The Long-Term Impact of Age and Hormonal Treatment

PURPOSE

The progression of deep endometriosis (DE) in women of reproductive age is highly variable. This study aimed to analyze the sonomorphological changes of rectal endometriosis over long periods of time and the influence of hormonal treatment.

METHODS

This retrospective study included premenopausal women with rectal DE treated conservatively between 2002 and 2021. The lesion length and thickness of the nodule were evaluated at regular intervals over time. We created statistical models with mixed effects to identify potential factors influencing lesion progression and regression.

RESULTS

38 patients were monitored over a mean period of 7.2 (± 4.2) years with a mean of 3.1 (± 2.1) check-ups within the observation period. We detected a significant increase in lesion length until the end of the fourth decade of life. In addition, we found a substantial decrease in the length and thickness of the nodule depending on the length of hormonal treatment.

CONCLUSION

In conservatively managed patients with rectal endometriosis, without hormonal therapy, lesion size can exhibit a moderate increase up to the end of the fourth decade of life, after which it appears to stabilize. This increase does not follow a linear pattern. Hormonal therapy is crucial in impeding further progression, resulting in either a cessation or a regression of lesion growth.

Intra- and interobserver reproducibility of transvaginal ultrasound for the detection and measurement of endometriotic lesions of the bowel

INTRODUCTION

The number and invasion depth of endometriotic bowel lesions, total length of bowel affected by endometriosis, lesion-to-anal verge distance, and extent of pouch of Douglas obliteration are important factors in preoperatively determining risk and complexity of endometriosis surgery. The intra- and interobserver reproducibility of transvaginal ultrasound in the evaluation of many of these parameters has not yet been investigated. Our study aimed to assess the intra- and interobserver reproducibility of transvaginal ultrasound between an experienced and less experienced examiner for all of these parameters.

MATERIAL AND METHODS

This prospective observational cross-sectional study was conducted between July 2019 and November 2020. Fifty consecutive premenopausal women who underwent transvaginal ultrasound examination in our clinic for the first time, were examined by the same two operators during the same attendance. Outcomes of interest were the inter-rater reproducibility of transvaginal ultrasound for detecting the presence, number, depth and size of bowel endometriotic nodules, lesion-to-anal-verge distance, total length of bowel affected, and pouch of Douglas obliteration. The intraobserver reproducibility was assessed for the continuous parameters. Cohen's kappa (κ) statistic, Cohen's weighted kappa (κ), proportions of agreement, intraclass correlation coefficient (ICC) and Bland-Altman limits of agreement were used to assess the reproducibility of the parameters.

RESULTS

The inter-rater agreement and reliability were very good for identifying bowel endometriosis, the number and invasion depth of bowel nodules, determining whether the maximum nodule length was <3 cm, and lesion-to-anal-verge distance <8 cm (proportion of agreement 0.92, 0.94, 0.97, 0.94, 0.96; κ 0.92, 0.91, 0.92, 0.82, 0.89). The inter-rater agreement and reliability were good for assessing pouch of Douglas obliteration (proportion of agreement 0.86, κ 0.80). The intra-rater reliability for the mean nodule diameter (ICC 0.93 and 0.97) and total length of bowel affected (ICC 0.94 and 0.91) were excellent for operators A and B, respectively. The inter-rater reliability for the mean nodule diameter was good (ICC 0.80), and moderate for the total length of bowel affected (ICC 0.70). The Bland-Altman limits of agreement demonstrated clinically acceptable ranges for these two parameters.

CONCLUSIONS

This study demonstrated a high intra- and inter-rater reproducibility of transvaginal ultrasound in the diagnosis of bowel endometriosis and measurement of its various components.

The Reproducibility of Ultrasonographic Findings of Rectosigmoid Endometriosis Among Examiners With Different Level of Expertise

OBJECTIVE

To analyze the reproducibility of ultrasonographic (US) findings of rectosigmoid endometriosis among examiners with different level of expertise using stored three-dimensional (3D) volumes of the posterior compartment of the pelvis as a part of SANABA (Sardinia-Navarra-Barcelona) collaborative study.

MATERIALS AND METHODS

Six examiners in 3 academic Department of Obstetrics and Gynecology, with different levels of experience and blinded to each other, evaluated 60 stored 3D volumes from the posterior compartment of the pelvis and looked for the presence or absence of features of rectosigmoid endometriotic lesions defined as an irregular hypoechoic nodule with or without hypoechoic foci at the level of the muscularis propria of the anterior wall rectum sigma. Multiplanar view and virtual navigation were used. All examiners had to assess the 3D volume of posterior compartment of the pelvis and classify it as present or absent disease. To analyze intra-observer and the inter-observer agreements, each examiner performed the assessment twice with a 2-week interval between the first and second assessments. Reproducibility was assessed by calculating the weighted Kappa index.

RESULTS

Intra-observer reproducibility was moderate to very good for all observers (Kappa index ranging from 0.49 to 0.96) associated with a good diagnostic accuracy of each reader. Inter-observer reproducibility was fair to very good (Kappa index range: 0.21-0.87).

CONCLUSIONS

The typical US sign of rectosigmoid endometriosis is reasonably recognizable to observers with different level of expertise when assessed in stored 3D volumes.

Transvaginal sonography determines accurately extent of infiltration of rectosigmoid deep endometriosis

OBJECTIVE

To investigate the agreement of measurements of the three diameters of rectosigmoid deep endometriosis (DE) lesions between presurgical evaluation using transvaginal sonography (TVS) and postsurgical specimen measurement (PSM).

METHODS

This was a prospective observational multicenter study including symptomatic women undergoing surgical treatment for DE involving the rectosigmoid, by either discoid or segmental resection, from April 2017 to December 2019. TVS was performed presurgically to evaluate lesion size (craniocaudal-midsagittal length, anteroposterior thickness and transverse diameter), in accordance with the International Deep Endometriosis Analysis (IDEA) group consensus statement, and was compared with PSM. The agreement of lesion dimensions between the two methods was assessed by Bland-Altman plots and limits of agreement and additionally by the intraclass correlation coefficient (ICC) and Pearson's correlation coefficient. Systematic and proportional bias was assessed using the paired t-test.

RESULTS

A total of 207 consecutive women were eligible for inclusion. Forty-one women were excluded, leaving 166 women for final analysis. A total of 123 segmental resections and 46 discoid resections were performed (both procedures were performed in three women). The mean difference between TVS and PSM was 0.90 (95% CI, 0.85-0.95) mm for lesion length measurements, 1.03 (95% CI, 0.98-1.09) mm for lesion thickness measurements and 0.84 (95% CI, 0.79-0.89) mm for transverse diameter measurements. Bland-Altman analysis demonstrated good agreement between the two methods for measurements of lesion length. Furthermore, there was good reliability and correlation between TVS and PSM for lesion length measurements, as demonstrated by an ICC of 0.82 (95% CI, 0.75-0.87) and Pearson's correlation coefficient of 0.72 (95% CI, 0.62-0.80), moderate-to-good reliability and correlation for lesion thickness measurements, with an ICC of 0.76 (95% CI, 0.67-0.82) and Pearson's correlation coefficient of 0.61 (95% CI, 0.51-0.70), and poor-to-moderate reliability and correlation for transverse diameter measurements, with an ICC of 0.58 (95% CI, 0.39-0.71) and Pearson's correlation coefficient of 0.46 (95% CI, 0.33-0.58).

CONCLUSION

Preoperative TVS determines accurately rectosigmoid DE lesion length. TVS can thereby contribute to optimal planning of surgical treatment options in women with rectosigmoid DE. © 2021 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

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

STUDY QUESTION

What is the interobserver and intraobserver reproducibility of pelvic ultrasound for the detection of endometriotic lesions?

SUMMARY ANSWER

Pelvic ultrasound is highly reproducible for the detection of pelvic endometriotic lesions.

WHAT IS KNOWN ALREADY

Transvaginal 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 DURATION

This 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 METHODS

The 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 CHANCE

There 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 CAUTION

Within 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 FINDINGS

These 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 INTERESTS

The authors have no conflict of interest. No funding was obtained for this work.

Conservative treatment of rectosigmoid endometriosis: A prospective study

INTRODUCTION

Deep infiltrating endometriosis is a common cause of pelvic pain. However, some patients have limited problems that may be controlled by medical treatment, so avoiding the potentially severe complications of major surgery. This approach requires detailed knowledge on quality of life and clinical symptoms over time. The aim of the study was to monitor these parameters in patients with rectosigmoid endometriosis treated with oral contraceptives, oral gestagens, and/or the levonorgestrel-releasing intrauterine device. Moreover, nodule size measurements performed with transvaginal sonography were correlated to severity of symptoms.

MATERIAL AND METHODS

Conservatively treated patients on oral contraceptives, oral gestagens, or the levonorgestrel-releasing intrauterine device underwent transvaginal sonography and answered a self-administered questionnaire regarding clinical symptoms and quality of life (Short Form 36 and Endometriosis Health Profile 30) at baseline, and 6 and 12 months later.

RESULTS

Eighty women completed the follow up. Scores of quality of life were comparable to normative data for Danish women of similar age and did not change with time. No association between change in size of the rectosigmoid nodule and change in symptoms was seen.

CONCLUSIONS

This study supports that simple treatment with oral contraceptives, oral gestagens, or the levonorgestrel-releasing intrauterine device represents a viable therapeutic approach to rectosigmoid Deep infiltrating endometriosis, provided that proper selection of patients in need of surgery exists.