Pelvic MRI in the diagnosis and staging of pelvic endometriosis: added value of structured reporting and expertise

O-RADS MRI risk stratification system: pearls and pitfalls

In 2021, the American College of Radiology (ACR) Ovarian-Adnexal Reporting and Data System (O-RADS) MRI Committee developed a risk stratification system and lexicon for assessing adnexal lesions using MRI. Like the BI-RADS classification, O-RADS MRI provides a standardized language for communication between radiologists and clinicians. It is essential for radiologists to be familiar with the O-RADS algorithmic approach to avoid misclassifications. Training, like that offered by International Ovarian Tumor Analysis (IOTA), is essential to ensure accurate and consistent application of the O-RADS MRI system. Tools such as the O-RADS MRI calculator aim to ensure an algorithmic approach. This review highlights the key teaching points, pearls, and pitfalls when using the O-RADS MRI risk stratification system.Critical relevance statement This article highlights the pearls and pitfalls of using the O-RADS MRI scoring system in clinical practice.Key points• Solid tissue is described as displaying post- contrast enhancement.• Endosalpingeal folds, fimbriated end of the tube, smooth wall, or septa are not solid tissue.• Low-risk TIC has no shoulder or plateau. An intermediate-risk TIC has a shoulder and plateau, though the shoulder is less steep compared to outer myometrium.

Noninvasive diagnostic imaging for endometriosis part 2: a systematic review of recent developments in magnetic resonance imaging, nuclear medicine and computed tomography

Endometriosis affects 1 in 9 women, taking 6.4 years to diagnose using conventional laparoscopy. Non-invasive imaging enables timelier diagnosis, reducing diagnostic delay, risk and expense of surgery. This review updates literature exploring the diagnostic value of specialist endometriosis magnetic resonance imaging (eMRI), nuclear medicine (NM) and computed tomography (CT). Searching after the 2016 IDEA consensus, 6192 publications were identified, with 27 studies focused on imaging for endometriosis. eMRI was the subject of 14 papers, NM and CT, 11, and artificial intelligence (AI) utilizing eMRI, 2. eMRI papers describe diagnostic accuracy for endometriosis, methodologies, and innovations. Advantages of eMRI include its: ability to diagnose endometriosis in those unable to tolerate transvaginal endometriosis ultrasound (eTVUS); a panoramic pelvic view, easy translation to surgical fields; identification of hyperintense iron in endometriotic lesions; and ability to identify super-pelvic lesions. Sequence standardization means eMRI is less operator-dependent than eTVUS, but higher costs limit its role to a secondary diagnostic modality. eMRI for deep and ovarian endometriosis has sensitivities of 91-93.5% and specificities of 86-87.5% making it reliable for surgical mapping and diagnosis. Superficial lesions too small for detection in larger capture sequences, means a negative eMRI doesn't exclude endometriosis. Combined with thin sequence capture and improved reader expertise, eMRI is poised for rapid adoption into clinical practice. NM labeling is diagnostically limited in absence of suitable unique marker for endometrial-like tissue. CT studies expose the reproductively aged to radiation. AI diagnostic tools, combining independent eMRI and eTVUS endometriosis markers, may result in powerful capability. Broader eMRI use, will optimize standards and protocols. Reporting systems correlating to surgical anatomy will facilitate interdisciplinary preoperative dialogues. eMRI endometriosis diagnosis should reduce repeat surgeries with mental and physical health benefits for patients. There is potential for early eMRI diagnoses to prevent chronic pain syndromes and protect fertility outcomes.

Do women with suspected endometriosis benefit from pelvic examination to improve diagnostic and management strategy?

OBJECTIVE

To analyze the literature and expose best evidence available regarding the benefit of pelvic examination for women with suspected endometriosis METHODS: the AGREE II and GRADE systems for grading scientific evidence.

RESULTS

Endometriosis is characterized by the heterogeneity in its clinical presentation with many different symptoms reported by patients. In the literature, questioning for each symptom has a high sensitivity, reaching 76-98 %, but lacks specificity (20 - 58 %). The symptom-based approach is limited by its low specificity, the absence of external validation for most of the models developed and the inability to characterize the extent of the disease, which could have major implications in the decision - making process. The latest systematic review and meta-analysis included a total of 30 studies with 4,565 participants, compared the diagnostic performance of several modalities for endometriosis. Physical examination had a pooled sensitivity of 71 % and a specificity of 69 %, with an average diagnostic accuracy of 0.76. Overall, the value of pelvic examination is conferred by its high positive likehood ratio and specificity. Besides its diagnostic value, pelvic examination improves patients' management by allowing the identification of a possible myofascial syndrome as a differential diagnosis. It also increases the quality of the preoperative workup and influences the quality of surgical excision and decreases the time to diagnosis.

CONCLUSION

Despite the lack of studies in the primary care context, pelvic examination (vaginal speculum and digital vaginal examination) increases the diagnostic value for suspected endometriosis in association with questioning for symptoms.

Surgical management of endometriosis to optimize fertility

PURPOSE OF REVIEW

Surgery is an integral element of treatment for infertility caused by endometriosis. This review summarizes the purported mechanisms of infertility in endometriosis, as well as the impacts of surgery for endometriosis on fertility, including pregnancy achieved spontaneously and with assisted reproductive technology (ART).

RECENT FINDINGS

Endometriosis' effect on fertility is multifactorial. The sequela of increased inflammation resulting from endometriosis causes alterations in ovarian, tubal, and uterine function. Removing or destroying these lesions reduces inflammation. Surgical treatment of both early-stage endometriosis and deeply infiltrating endometriosis improves spontaneous pregnancy rates and ART pregnancy rates. Conventional or robotic laparoscopy is the preferred surgical approach.

SUMMARY

Endometriosis has detrimental effects on fertility, including negative impacts on oocyte, tubal, and endometrial function. Laparoscopic surgery for endometriosis elevates both spontaneous and ART pregnancy rates above those achieved with expectant management alone. The resection or destruction of endometriosis implants reduces inflammation, which likely improves the multifactorial infertility related to endometriosis. This topic is complex and controversial; more research in the form of high-quality randomized control trials is needed.

MRI of endometriosis in correlation with the #Enzian classification: applicability and structured report

Endometriosis represents one of the most common causes of life-impacting chronic pelvic pain and female infertility. Magnetic resonance imaging (MRI) plays an increasing role in the diagnosis and mapping of endometriosis, while diagnostic laparoscopy currently tends to be reserved for the patients with negative imaging results. The #Enzian, published in 2021, proposes a new comprehensive classification system of endometriosis, combining a complete staging of deep infiltrative endometriosis with the evaluation of peritoneal/ovarian/tubal localizations and the presence of adenomyosis. This article addresses in detail the applicability of the #Enzian classification, primarily based on surgical findings, to the MRI evaluation of the endometriosis. Overall, there is a significant matching between MRI features and the #Enzian classification criteria, two different perspectives of endometriosis mapping, with different goals and levels of detail. The main discrepancy lies in the evaluation of tubo-ovarian condition, which is not fully assessable by MRI. Furthermore, as endometriosis is a complex disease, usually multifocal, that can present with a myriad of imaging findings, MRI reporting should be clear and well organized. The authors group, both radiologists and gynecologists, propose a structured MRI report of endometriosis in correlation with the #Enzian classification, merging the detailed anatomical and pre-operative information provided by the MRI with the benefits of a comprehensive classification system of endometriosis in the clinical practice and research field.Critical relevance statement This article addresses in detail the applicability of the #Enzian classification, primarily based on surgical findings, to the MRI evaluation of the endometriosis and proposes a #Enzian-based structured MRI report.

[Pelvic exam in gynecology and obstetrics: Guidelines for clinical practice]

OBJECTIVE

To provide guidelines for the pelvic clinical exam in gynecology and obstetrics.

MATERIAL AND METHODS

A multidisciplinary experts consensus committee of 45 experts was formed, including representatives of patients' associations and users of the health system. The entire guidelines process was conducted independently of any funding. The authors were advised to follow the rules of the Grading of Recommendations Assessment, Development and Evaluation (GRADE®) system to guide assessment of quality of evidence. The potential drawbacks of making strong recommendations in the presence of low-quality evidence were emphasized.

METHODS

The committee studied 40 questions within 4 fields for symptomatic or asymptomatic women (emergency conditions, gynecological consultation, gynecological diseases, obstetrics, and pregnancy). Each question was formulated in a PICO (Patients, Intervention, Comparison, Outcome) format and the evidence profiles were produced. The literature review and recommendations were made according to the GRADE® methodology.

RESULTS

The experts' synthesis work and the application of the GRADE method resulted in 27 recommendations. Among the formalized recommendations, 17 present a strong agreement, 7 a weak agreement and 3 an expert consensus agreement. Thirteen questions resulted in an absence of recommendation due to lack of evidence in the literature.

CONCLUSIONS

The need to perform clinical examination in gynecological and obstetrics patients was specified in 27 pre-defined situations based on scientific evidence. More research is required to investigate the benefit in other cases.

The role of minimally invasive gynecologic surgeons in the era of subspecialties: when to refer and consult

PURPOSE OF REVIEW

Minimally invasive gynecologic surgery (MIGS) is a subspecialty focus of obstetrics and gynecology with focused expertise on complex benign gynecologic disorders. To date, no formal recommendations have been made in defining a referral system for MIGS. This article reviews the evidence regarding common disorders and procedures and their outcomes, and posits a basis for MIGS referral.

RECENT FINDINGS

In instances where intraoperative and perioperative features may pose clinical challenges to the surgeon and ultimately the patient, the literature suggests the following scenarios may have adverse outcomes, and therefore, benefit from the skills of MIGS subspecialists: fibroids - at least five myomas, myoma size at least 9 cm, and suspected myoma weight at least 500 g; endometriosis - presence of endometrioma(s), suspected stage III/IV endometriosis, and requirement for advanced adjunct procedures; hysterectomy - uteri at least 250 g or 12 weeks estimated size, at least three prior laparotomies, obesity, and complex surgical history with suspected adhesive disease.

SUMMARY

A referral system for MIGS subspecialists has proven benefits for both the gynecologic surgical community as well as the patients and their outcomes. This article provides evidence for collaboration with MIGS especially as it relates to leiomyomatous uteri, endometriosis, and complex hysterectomies.

Infertility workup: identifying endometriosis

Endometriosis was classically diagnosed during diagnostic laparoscopies, which used to be routinely performed up until a decade ago or so. This practice fitted with the long-held belief that surgery was the gold standard for diagnosing endometriosis. Today, the abandon of routine diagnostic laparoscopies-in favor of assisted reproductive technology-first therapeutic approaches-has created a void for diagnosing endometriosis. Modern-day imaging techniques-ultrasound and magnetic resonance imaging-when used with a systematic approach have offered a reliable replacement option for diagnosing endometriosis. In infertility, endometriosis should be identified or excluded on the basis of past history or confirmation or exclusion suspicion on the basis of history and/or physical examination.

Can New ENZIAN Score 2020 Represent a Staging System Improving MRI Structured Report?

Structured reporting systems for endometriotic disease are gaining a central role in diagnostic imaging: our aim is to evaluate applicability and the feasibility of the recent ENZIAN score (2020) assessed by MRI. A total of 60 patients with suspected tubo–ovarian/deep endometriosis were retrospectively included in our study according to the following criteria: availability of MR examination; histopathological results from laparoscopic or surgical treatment; patients were not assuming estro-progestin or progestin therapy. Three different readers (radiologists with 2-, 5-, and 20-years of experience in pelvic imaging) have separately assigned a score according to the ENZIAN score (revised 2020) for all lesions detected by magnetic resonance imaging (MRI). Our study showed a high interobserver agreement and feasibility of the recent ENZIAN score applied to MRI; on the other hand, our experience highlighted some limitations mainly due to MRI’s inability to assess tubal patency and mobility, as required by the recent score (2020). In view of the limitations which arose from our study, we propose a modified MRI-ENZIAN score that provides a complete structured reporting system, more suitable for MRI. The high interobserver agreement of the recent ENZIAN score applied to MRI confirms its validity as a complete staging system for endometriosis, offering a shared language between radiologists and surgeons.

Reproducibility of MRI Features of Uterine Leiomyomas: A Study on Interobserver Agreement and Inter-Method Agreement With Surgery

PURPOSE

To evaluate interobserver agreement in the interpretation of different MRI features of uterine leiomyomas (UL) according to observers' experience, and to assess the inter-method reproducibility (MRI versus surgery) regarding the International Federation of Gynecology and Obstetrics (FIGO) classification.

METHODS

Retrospective study including UL patients who underwent MRI and surgical treatment. Four blinded observers (2 vs >10 years of experience) assessed UL regarding dimensions and volume; inner and outer mantles; FIGO classification; vascularization; degeneration; and diffusion-weighted imaging features. Uterine dimensions and volume were calculated. FIGO classification as ascertained by observers was compared to surgical findings. Intraclass correlation coefficient (ICC) estimates were used for interobserver comparison of numerical variables, and kappa statistic for categorical variables.

RESULTS

Thirty-five patients (26y-73y) with 61 UL were included in the interobserver analyses, and 31 patients (54 UL) had available data allowing retrospective surgical FIGO classification for assessment of inter-method reproducibility. Both groups of observers had good to excellent agreement in assessing UL (ICC = 0.980-0.994) and uterine volumes (ICC = 0.857-0.914), mantles measurement (ICC = 0.797-0.920), and apparent diffusion coefficient calculation (ICC = 0.787-0.883). There was substantial agreement for both groups regarding FIGO classification (κ = 0.645-0.767). Vascularization, degeneration and restricted diffusion had lower agreement, varying from reasonable to moderate. Inter-method agreement was reasonable (κ = 0.341-0.395).

CONCLUSIONS

Interobserver agreement of MRI for UL was higher for quantitative than qualitative features, with a little impact of observers' experience for most features. MRI agreement with surgery was reasonable. Further efforts should be taken to improve interobserver and inter-method reproducibility for MRI in this scenario.

Performance of imaging interpretation, intra- and inter-reader agreement for diagnosis of pelvic endometriosis: comparison between an abbreviated and full MRI protocol

PURPOSE

To compare the performance of imaging interpretation, intra- and inter-reader agreement between an abbreviated (aMRI) and full (fMRI) MRI protocol for diagnosis of pelvic endometriosis.

METHODS

Seventy consecutive fMRI exams performed under suspicion of pelvic endometriosis were selected. Four radiologists (Rd) (1-10 years experience) independently evaluated presence/absence of endometriosis at 9 anatomic sites (AS). The readers evaluated aMRI (coronal T2 TSE volumetric images and axial T1 GRE fat-sat without contrast, extracted from fMRI) and fMRI protocols randomly, with at least 4 weeks interval between readings. The degree of confidence for diagnosis at each AS was evaluated with a 1-3 Likert Scale (1: low; 3: high). Intra- and inter-reader agreement between protocols were evaluated by kappa statistics and took reading experience into account. The gold standard for assessing the performance of imaging interpretation (sensitivity, specificity and accuracy) used a consensus reading of two other Rd (> 15 years experience).

RESULTS

There was no significant difference in the accuracy of imaging interpretation between the abbreviated (0.83-0.86) and full (0.83-0.87) protocols (p = 0.15). Intra-reader agreement between protocols ranged from substantial to almost perfect (0.74-0.96). A substantial inter-reader agreement was found for both protocols for readers with similar levels of experience (0.67-0.69) and in the global analysis (0.66 for both protocols). No difference was found in terms of degree of confidence between protocols, for all readers.

CONCLUSION

An abbreviated MRI protocol for pelvic endometriosis provided an accuracy of interpretation comparable to that of a complete protocol, with similar degrees of confidence and reproducibility, regardless the level of experience.

MRI sliding sign: Using MRI to assess rectouterine mobility in pelvic endometriosis

INTRODUCTION

Surgical excision of deep infiltrating endometriosis (DIE) is complex and associated with morbidity. Diagnostic imaging plays an important role in the preoperative workup. We sought to determine the utility of single sagittal T2-weighted MRI motion sequence in the preoperative assessment of pelvic mobility in patients with endometriosis.

METHODS

An observational study at a single tertiary public referral centre in Australia. Eighty-one MRI studies from 1 May 2019 to 3 December 2019, were enrolled. Studies were included if they were performed to stage endometriosis, including a T2-weighted motion series, adequately covering a uterus, cervix and rectum. Fifty-seven studies met inclusion criteria. The reference standard was a contemporaneous transvaginal ultrasound (TVUS) reporting on pelvic organ mobility. Three subspecialist radiologists were then blindly asked to identify, on the cine loop: rectouterine immobility, superficial endometriosis (pelvic bowel adhesions), rectosigmoid Deep Infiltrating Endometriosis (DIE). Fleiss' Kappa assessed interobserver agreement. Consensus MRI sensitivity and specificity were estimated against the reference standard (TVUS).

RESULTS

Median age was 35 years (range 19-51). Forty-three cases had a contemporaneous TVUS; 14 reporting a sliding sign, 29 with fixed pelves. Interobserver agreement was 'substantial' (k = 0.79) for absent MRI sliding sign and 'almost perfect' (k = 0.90) for absence of DIE. Consensus MRI had 90% sensitivity (95% CI 73-98%) for pelvic immobility at TVUS (absent sliding sign). Interobserver agreement and consensus MRI sensitivity were higher for adhesions and immobility than normal findings.

CONCLUSION

An MRI motion sequence can identify patients with pelvic adhesions and immobility, helping determine surgical difficulty when TVUS is not diagnostic.

Structured MRI reporting increases completeness of radiological reports and requesting physicians' satisfaction in the diagnostic workup for pelvic endometriosis

PURPOSE

MRI plays an important role in the diagnosis and surgical planning of pelvic endometriosis (PE), and imaging reports should contain all relevant information (completeness). As structured reports are being increasingly utilized, we aimed to evaluate whether structured MRI reporting increases the quality of reports regarding completeness and, consequently, their perceived value by gynecologists, in comparison to free-text reports. We also aimed to compare the diagnostic performance of both formats.

METHODS

We retrospectively included 28 consecutive women with histologically proven PE who underwent MRI within one month before surgery. Two abdominal radiologists (Rd1/Rd2, 3y/12y experience), blinded to clinical and surgical data, individually elaborated free-text reports and, four months later, structured reports. Completeness (defined as description of six key anatomical sites deemed essential for surgical planning in a consensus of four-blinded external experts) and diagnostic performance (sensitivity and specificity) by site (histology as reference) were compared between reports using the McNemar test. The satisfaction of gynecologists was compared using the marginal homogeneity test.

RESULTS

Structured reporting increased completeness for both Rd1 (rectosigmoid, retrocervical/uterosacral ligament, vagina, and ureter) and Rd2 (vagina, ureter, and bladder) (p < 0.05), without compromising sensitivity or specificity at any of the evaluated sites. Gynecologists' satisfaction was superior with structured reports in most comparisons.

CONCLUSION

Structured MRI reports perform better in fully documenting essential features of PE and are similar in terms of diagnostic performance, therefore having higher potential for surgical planning. Gynecologists found them easier to assess and were more satisfied with the information provided by structured reports.

State of the art in abdominal MRI structured reporting: a review

In the management of several abdominal disorders, magnetic resonance imaging (MRI) has the potential to significantly improve patient's outcome due to its diagnostic accuracy leading to more appropriate treatment choice. However, its clinical value heavily relies on the quality and quantity of diagnostic information that radiologists manage to convey through their reports. To solve issues such as ambiguity and lack of comprehensiveness that can occur with conventional narrative reports, the adoption of structured reporting has been proposed. Using a checklist and standardized lexicon, structured reports are designed to increase clarity while assuring that all key imaging findings related to a specific disorder are included. Unfortunately, structured reports have their limitations too, such as risk of undue report simplification and poor template plasticity. Their adoption is also far from widespread, and probably the ideal balance between radiologist autonomy and report consistency of has yet to be found. In this article, we aimed to provide an overview of structured reporting proposals for abdominal MRI and of works assessing its value in comparison to conventional free-text reporting. While for several abdominal disorders there are structured templates that have been endorsed by scientific societies and their adoption might be beneficial, stronger evidence confirming their imperativeness and added value in terms of clinical practice is needed, especially regarding the improvement of patient outcome.

Structured manual for MRI assessment of deep infiltrating endometriosis using the ENZIAN classification

PURPOSE

Proposal of a systematic approach to assess Deep infiltrating endometriosis (DIE) through pelvic Magnetic resonance imaging (MRI) using the Enzian classification and examination of inter-rater agreement.

METHODS

Three radiologists reviewed 23 MRI of patients with pelvic DIE at one tertiary referral center retrospectively and independently. Inclusion criteria were intraoperative confirmation of DIE and MR imaging according to ESUR (European Society of Urogenital Radiology) guidelines. Assessment of the anatomical pelvic compartments was performed using a manual based on the Enzian classification with step-by-step instructions using recommended planes and sequences presented here. Interrater agreement was measured using kappa statistics.

RESULTS

According to the intraoperative site lesions in 53 anatomical compartments were present. Interrater agreement was best for compartments A (0.255) and FB (0.642). For FI (0.204) and B (0.146) it was slight, there was poor agreement for C (- 0.263), FA (- 0.022), and FO (- 0.030), respectively, and as for FU, no ureter infiltration was described.

CONCLUSION

MRI as a noninvasive diagnostic tool offers essential advantages regarding classification and therapy planning for patients with DIE. However, its assessment is difficult and a more systematic approach is needed. Our proposed manual based on the Enzian classification is reproducible and could support radiologists and gynecologists.