Endometriosis MRI lexicon: consensus statement from the society of abdominal radiology endometriosis disease-focused panel

Magnetic Resonance Imaging of Endometriosis: The Role of Advanced Techniques

Endometriosis is a chronic inflammatory disease that affects about 10% of women, and it is characterized by the presence of endometrial tissue outside the uterine cavity. Associated symptoms are dyspareunia, chronic pelvic pain, and infertility. The diagnosis of endometriosis can be challenging due to various clinical and imaging presentations. Laparoscopy is the gold standard for the diagnosis, but it is an invasive procedure. The literature has increasingly promoted a switch to less invasive imaging techniques, such as ultrasound and magnetic resonance imaging (MRI). The latter, also in relation to the latest technological advances, allows a comprehensive and accurate assessment of the pelvis and it can also identify sites of endometriosis that escape laparoscopic evaluation. Furthermore, MRI has been found to be more accurate than other imaging techniques in relation to its improved sensitivity and specificity in identifying disease sites, also due to the role of new emerging sequences. This article aims to review the current role of advanced MRI applications in the assessment of endometriosis.

MRI for endometriosis in adolescent patients

Endometriosis, a chronic condition that often starts in adolescence, can have a significant impact on quality of life due to symptoms of dysmenorrhea and pelvic pain. Although laparoscopy with direct visualization and pathologic correlation is the reference standard for the diagnosis of endometriosis, some authors have called for a greater emphasis on clinical diagnosis - including imaging. Magnetic resonance imaging (MRI) provides highly reproducible, large field of view, multiplanar, and multiparametric imaging of pelvic endometriosis and is well tolerated in adolescent patients. As such, pediatric radiologists need to be familiar with the manifestations of endometriosis on MRI and how these findings may differ from those seen in adult populations.

Best Practices: Ultrasound Versus MRI in the Assessment of Pelvic Endometriosis

Endometriosis is a common yet morbid disease. Imaging plays an important role in diagnosis and treatment planning. Both ultrasound (US) and MRI are used to detect disease. We performed a literature review to assess whether one is superior. A total of 33 studies from the 4482 identified in the initial search were found to assess the efficacy of US and/or MRI in detecting pelvic endometriosis. Most studies were performed at centers with extensive experience with endometriosis, using dedicated US and MRI protocols. A wide range of sensitivities and specificities was reported, but overall weighted means of diagnostic statistics between US and MRI were similar. The choice of dedicated US versus MRI in evaluation of endometriosis should therefore be based on the expertise in the region. The data also showed US had better accuracy for identifying depth of wall invasion in bowel wall disease, whereas MRI better visualized pelvic wall and extraperitoneal disease. Routine US and MRI protocols performed worse than dedicated US and MRI protocols, which may account for delays in diagnoses. Clinical and research efforts directed at improving the sensitivity of routine imaging for diagnosing deep endometriosis could improve patient access to appropriate care.

Reasons why it is time to change imaging guidelines on endometriosis

In light of the rising number of patients referred for magnetic resonance imaging (MRI) due to suspected endometriosis and the high expectations of these patients, there is a need for new imaging guidelines to optimally protocol and indicate MRI and transvaginal ultrasonography (TVUS) examinations. This is crucial for accurately addressing the inquiries of gynecologists, encompassing complete mapping and preoperative staging, and facilitating effective communication with patients. In this context, the development of a standardized lexicon, as well as dedicated imaging classifications, is recommended to aid in the comprehensive management of patients. CLINICAL RELEVANCE STATEMENT: The radiologist should use a standardized lexicon and provide a score along with details about the specific compartments affected by endometriosis disease. This helps in offering clearer guidance to the surgeon. KEY POINTS: • An optimal staging is based on the combination of clinical examination, transvaginal US, and MRI. • MRI is able to detect location that is hidden at the beginning of a laparoscopic surgery and thus the need for dedicated MR classifications to correctly stage the disease. • Deep pelvic endometriosis index (dPEI) classification is externally validated and highly correlated with operating time, hospital stay, and postoperative complications.

Radiology State-of-the-art Review: Endometriosis Imaging Interpretation and Reporting

Endometriosis is a common condition impacting approximately 190 million individuals and up to 50% of women with infertility globally. The disease is characterized by endometrial-like tissue located outside of the uterine corpus, which causes cyclical hemorrhage, inflammation, and fibrosis. Based on clinical suspicion or findings at routine transvaginal pelvic US or other prior imaging, dedicated imaging for endometriosis may be warranted with MRI or advanced transvaginal US. Deep endometriosis (DE) in the pelvis includes evaluation for stromal and fibrotic components and architectural distortion resulting from fibrosis and tethering. It is a disease requiring a compartment-based, pattern-recognition approach. MRI has the benefit of global assessment of the pelvis and is effective in assessing for features of malignancy and for evaluating extrapelvic locations. Transvaginal US has the advantage of dynamic maneuvers to assess for adhesions and may achieve higher spatial resolution for assessing the depth of bowel wall invasion. T1-weighted MRI evaluation increases the specificity of diagnosis by identifying hemorrhagic components, but the presence of T1 signal hyperintensity is not essential for diagnosing DE. Endometriosis is a disease with a broad spectrum; understanding the mild through advanced manifestations, including malignancy evaluation, is within the scope and breadth of radiologists' interpretation.

Endometriosis, a common but enigmatic disease with many faces: current concept of pathophysiology, and diagnostic strategy

Endometriosis is a benign, common, but controversial disease due to its enigmatic etiopathogenesis and biological behavior. Recent studies suggest multiple genetic, and environmental factors may affect its onset and development. Genomic analysis revealed the presence of cancer-associated gene mutations, which may reflect the neoplastic aspect of endometriosis. The management has changed dramatically with the development of fertility-preserving, minimally invasive therapies. Diagnostic strategies based on these recent basic and clinical findings are reviewed. With a focus on the presentation of clinical cases, we discuss the imaging manifestations of endometriomas, deep endometriosis, less common site and rare site endometriosis, various complications, endometriosis-associated tumor-like lesions, and malignant transformation, with pathophysiologic conditions.

Non-Invasive Imaging Techniques for Diagnosis of Pelvic Deep Endometriosis and Endometriosis Classification Systems: An International Consensus Statement

The International Society of Ultrasound in Obstetrics and Gynecology (ISUOG) and International Deep Endometriosis Analysis (IDEA) group, the European Endometriosis League (EEL), the European Society for Gynaecological Endoscopy (ESGE), the European Society of Human Reproduction and Embryology (ESHRE), the International Society for Gynecologic Endoscopy (ISGE), the American Association of Gynecologic Laparoscopists (AAGL) and the European Society of Urogenital Radiology (ESUR) elected an international, multidisciplinary panel of gynecological surgeons, sonographers and radiologists, including a steering committee, which searched the literature for relevant articles in order to review the literature and provide evidence-based and clinically relevant statements on the use of imaging techniques for non-invasive diagnosis and classification of pelvic deep endometriosis. Preliminary statements were drafted based on review of the relevant literature. Following two rounds of revisions and voting orchestrated by chairs of the participating societies, consensus statements were finalized. A final version of the document was then resubmitted to the society chairs for approval. Twenty statements were drafted, of which 14 reached strong and three moderate agreement after the first voting round. The remaining three statements were discussed by all members of the steering committee and society chairs and rephrased, followed by an additional round of voting. At the conclusion of the process, 14 statements had strong and five statements moderate agreement, with one statement left in equipoise. This consensus work aims to guide clinicians involved in treating women with suspected endometriosis during patient assessment, counseling and planning of surgical treatment strategies.

Non-invasive imaging techniques for diagnosis of pelvic deep endometriosis and endometriosis classification systems: an International Consensus Statement

The International Society of Ultrasound in Obstetrics and Gynecology (ISUOG) and International Deep Endometriosis Analysis (IDEA) group, the European Endometriosis League (EEL), the European Society for Gynaecological Endoscopy (ESGE), the European Society of Human Reproduction and Embryology (ESHRE), the International Society for Gynecologic Endoscopy (ISGE), the American Association of Gynecologic Laparoscopists (AAGL) and the European Society of Urogenital Radiology (ESUR) elected an international, multidisciplinary panel of gynecological surgeons, sonographers and radiologists, including a steering committee, which searched the literature for relevant articles in order to review the literature and provide evidence-based and clinically relevant statements on the use of imaging techniques for non-invasive diagnosis and classification of pelvic deep endometriosis. Preliminary statements were drafted based on review of the relevant literature. Following two rounds of revisions and voting orchestrated by chairs of the participating societies, consensus statements were finalized. A final version of the document was then resubmitted to the society chairs for approval. Twenty statements were drafted, of which 14 reached strong and three moderate agreement after the first voting round. The remaining three statements were discussed by all members of the steering committee and society chairs and rephrased, followed by an additional round of voting. At the conclusion of the process, 14 statements had strong and five statements moderate agreement, with one statement left in equipoise. This consensus work aims to guide clinicians involved in treating women with suspected endometriosis during patient assessment, counseling and planning of surgical treatment strategies. © 2024 The Authors. Published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology, by Universa Press, by The International Society for Gynecologic Endoscopy, by Oxford University Press on behalf of European Society of Human Reproduction and Embryology, by Elsevier Inc. on behalf of American Association of Gynecologic Laparoscopists and by Elsevier B.V.

Non-invasive imaging techniques for diagnosis of pelvic deep endometriosis and endometriosis classification systems: an International Consensus Statement†,‡

The International Society of Ultrasound in Obstetrics and Gynecology (ISUOG) and International Deep Endometriosis Analysis (IDEA) group, the European Endometriosis League (EEL), the European Society for Gynaecological Endoscopy (ESGE), the European Society of Human Reproduction and Embryology (ESHRE), the International Society for Gynecologic Endoscopy (ISGE), the American Association of Gynecologic Laparoscopists (AAGL) and the European Society of Urogenital Radiology (ESUR) elected an international, multidisciplinary panel of gynecological surgeons, sonographers and radiologists, including a steering committee, which searched the literature for relevant articles in order to review the literature and provide evidence-based and clinically relevant statements on the use of imaging techniques for non-invasive diagnosis and classification of pelvic deep endometriosis. Preliminary statements were drafted based on a review of the relevant literature. Following two rounds of revisions and voting orchestrated by chairs of the participating societies, consensus statements were finalized. A final version of the document was then resubmitted to the society chairs for approval. Twenty statements were drafted, of which 14 reached strong and three moderate agreement after the first voting round. The remaining three statements were discussed by all members of the steering committee and society chairs and rephrased, followed by an additional round of voting. At the conclusion of the process, 14 statements had strong and five statements moderate agreement, with one statement left in equipoise. This consensus work aims to guide clinicians involved in treating women with suspected endometriosis during patient assessment, counselling and planning of surgical treatment strategies.

Non-invasive imaging techniques for diagnosis of pelvic deep endometriosis and endometriosis classification systems: an International Consensus Statement. Hum Reprod Open 2024;2024:hoae029. [PMID: 38812884 PMCID: PMC11134890 DOI: 10.1093/hropen/hoae029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

The International Society of Ultrasound in Obstetrics and Gynecology (ISUOG) and International Deep Endometriosis Analysis (IDEA) group, the European Endometriosis League (EEL), the European Society for Gynaecological Endoscopy (ESGE), ESHRE, the International Society for Gynecologic Endoscopy (ISGE), the American Association of Gynecologic Laparoscopists (AAGL) and the European Society of Urogenital Radiology (ESUR) elected an international, multidisciplinary panel of gynecological surgeons, sonographers, and radiologists, including a steering committee, which searched the literature for relevant articles in order to review the literature and provide evidence-based and clinically relevant statements on the use of imaging techniques for non-invasive diagnosis and classification of pelvic deep endometriosis. Preliminary statements were drafted based on review of the relevant literature. Following two rounds of revisions and voting orchestrated by chairs of the participating societies, consensus statements were finalized. A final version of the document was then resubmitted to the society chairs for approval. Twenty statements were drafted, of which 14 reached strong and three moderate agreement after the first voting round. The remaining three statements were discussed by all members of the steering committee and society chairs and rephrased, followed by an additional round of voting. At the conclusion of the process, 14 statements had strong and five statements moderate agreement, with one statement left in equipoise. This consensus work aims to guide clinicians involved in treating women with suspected endometriosis during patient assessment, counselling, and planning of surgical treatment strategies.

Giant endometrioma in an asymptomatic patient

Endometriosis is a chronic inflammatory gynecologic disorder characterized by the presence of endometrial-like tissue, including endometrial glands and stroma, outside of the uterine cavity. It is a prevalent condition worldwide, affecting approximately 10% of reproductive-age women and up to 50% of infertile women. Endometriosis manifests in three ways: superficial peritoneal endometriosis, deep infiltrative endometriosis, and ovarian endometriomas, with the possibility of coexistence among them. The disease presents with a range of symptoms, including chronic pelvic pain, dysmenorrhea, dyspareunia, and infertility. Additionally, patients may experience nongynecological symptoms such as dyschezia, dysuria, hematuria, flank pain, and fatigue, among others. The ovaries are the most affected site in endometriosis, typically with cysts measuring less than 6 cm in diameter. Therefore, even in the presence of a large ovarian cyst or in asymptomatic patients, the consideration of an endometrial cyst should not be overlooked.

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.

Endometriosis MR mimickers: T2-hypointense lesions

Endometriosis is a common crippling disease in women of reproductive age. Magnetic resonance imaging (MRI) is considered the cornerstone radiological technique for both the diagnosis and management of endometriosis. While its sensitivity, especially in deep infiltrating endometriosis, is superior to that of ultrasonography, many sources of false-positive results exist, leading to a lack of specificity. Hypointense lesions or pseudo-lesions on T2-weighted images include anatomical variants, fibrous connective tissues, benign and malignant tumors, feces, surgical materials, and post treatment scars which may mimic deep pelvic infiltrating endometriosis. False positives can have a major impact on patient management, from diagnosis to medical or surgical treatment. This educational review aims to help the radiologist acknowledge MRI criteria, pitfalls, and the differential diagnosis of deep pelvic infiltrating endometriosis to reduce false-positive results. Critical relevance statement MRI in deep infiltrating endometriosis has a 23% false-positive rate, leading to misdiagnosis. T2-hypointense lesions primarily result from anatomical variations, fibrous connective tissue, benign and malignant tumors, feces, surgical material, and post-treatment scars. Key points • MRI in DIE has a 23% false-positive rate, leading to potential misdiagnosis.• Anatomical variations, fibrous connective tissues, neoplasms, and surgical alterations are the main sources of T2-hypointense mimickers.• Multisequence interpretation, morphologic assessment, and precise anatomic localization are crucial to prevent overdiagnosis.• Gadolinium injection is beneficial for assessing endometriosis differential diagnosis only in specific conditions.

Endometriosis MR mimickers: T1-hyperintense lesions

Endometriosis is a chronic and disabling gynecological disease that affects women of reproductive age. Magnetic resonance imaging (MRI) is considered the cornerstone radiological technique for both the diagnosis and management of endometriosis. While MRI offers higher sensitivity compared to ultrasonography, it is prone to false-positive results, leading to decreased specificity. False-positive findings can arise from various T1-hyperintense conditions on fat-suppressed T1-weighted images, resembling endometriotic cystic lesions in different anatomical compartments. These conditions include hemorrhage, hyperproteic content, MRI artifacts, feces, or melanin. Such false positives can have significant implications for patient care, ranging from incorrect diagnoses to unnecessary medical or surgical interventions and subsequent follow-up. To address these challenges, this educational review aims to provide radiologists with comprehensive knowledge about MRI criteria, potential pitfalls, and differential diagnoses, ultimately reducing false-positive results related to T1-hyperintense abnormalities.Critical relevance statementMRI has a 10% false-positive rate, leading to misdiagnosis. T1-hyperintense lesions, observed in the three phenotypes of pelvic endometriosis, can also be seen in various other causes, mainly caused by hemorrhages, high protein concentrations, and artifacts.Key points• MRI in endometriosis has a 10% false-positive rate, leading to potential misdiagnosis.• Pelvic endometriosis lesions can exhibit T1-hyperintensity across their three phenotypes.• A definitive diagnosis of a T1-hyperintense endometriotic lesion is crucial for patient management.• Hemorrhages, high protein concentrations, lipids, and artifacts are the main sources of T1-hyperintense mimickers.

Potential applications of PET/MRI in non-oncologic conditions within the abdomen and pelvis

PET/MRI is a relatively new imaging modality with several advantages over PET/CT that promise to improve imaging of the abdomen and pelvis for specific diagnostic tasks by combining the superior soft tissue characterization of MRI with the functional information acquired from PET. PET/MRI has an established role in staging and response assessment of multiple abdominopelvic malignancies, but the modality is not yet established for non-oncologic conditions of the abdomen and pelvis. In this review, potential applications of PET/MRI for non-oncologic conditions of abdomen and pelvis are outlined, and the available literature is reviewed to highlight promising areas for further research and translation into clinical practice.

Gynaecological Causes of Acute Pelvic Pain: Common and Not-So-Common Imaging Findings

In female patients, acute pelvic pain can be caused by gynaecological, gastrointestinal, and urinary tract pathologies. Due to the variety of diagnostic possibilities, the correct assessment of these patients may be challenging. The most frequent gynaecological causes of acute pelvic pain in non-pregnant women are pelvic inflammatory disease, ruptured ovarian cysts, ovarian torsion, and degeneration or torsion of uterine leiomyomas. On the other hand, spontaneous abortion, ectopic pregnancy, and placental disorders are the most frequent gynaecological entities to cause acute pelvic pain in pregnant patients. Ultrasound (US) is usually the first-line diagnostic technique because of its sensitivity across most common aetiologies and its lack of radiation exposure. Computed tomography (CT) may be performed if ultrasound findings are equivocal or if a gynaecologic disease is not initially suspected. Magnetic resonance imaging (MRI) is an extremely useful second-line technique for further characterisation after US or CT. This pictorial review aims to review the spectrum of gynaecological entities that may manifest as acute pelvic pain in the emergency department and to describe the imaging findings of these gynaecological conditions obtained with different imaging techniques.

Feasibility of periprocedural decision on the administration of intravenous contrast media in MRI for endometriosis

PURPOSE

To assess the feasibility of a periprocedural decision on the administration of intravenous contrast media in MRI for endometriosis and to evaluate the frequency and reasons of contrast administrations, the corresponding MRI diagnoses, and outcome.

METHODS

In this retrospective, descriptive cross-sectional single-center study all patients were included, who received a pelvic MRI for evaluation of endometriosis between April 2021 and February 2023. Frequency and reasons of optional intravenous administration of contrast media, corresponding MRI diagnoses and clinical outcome data were noted after re-review of all images, review of radiology reports and review of patients' medical records. The decision on the administration of intravenous contrast media had been made by experienced radiologists, depending on the findings of the non-contrast sequences and the presence of ancillary questions.

RESULTS

303 consecutive patients (mean age, 33.4 years +/- 8.3 [standard deviation]) were evaluated. Periprocedural decision on the administration of intravenous contrast media had been made in all cases. For 219/303 (72.3%) patients, it was decided after review of the non-contrast sequences and exclusion of ancillary questions that contrast administration was not required. 84/303 (27.7%) patients received contrast media, and the most frequent reasons were indeterminate ovarian lesion (41/84 cases, 48.8%) or suspicion of pelvic venous congestion syndrome (26/84 cases, 31.0%). No relevant differences in patient outcomes could be noted (non-contrast/contrast MRI).

CONCLUSIONS

A periprocedural decision on the administration of contrast media in MRI for endometriosis is feasible with little effort. It allows the administration of contrast media to be avoided in most cases. If the administration of contrast media is deemed necessary, repeat examinations can be avoided.

Caesarean-section scar endometriosis (CSSE): clinical and imaging fundamentals of an underestimated entity

Caesarean-section scar endometriosis (CSSE) is a form of extra-pelvic endometriosis developing through endometrial cell implantation anywhere along the route of a previous caesarean section (CS) surgery, including the skin, subcutaneous tissue, abdominal wall muscles, intraperitoneally, and the uterine scar itself. Synchronous intra-abdominal endometriosis is not a prerequisite. Given the rising prevalence of CS, CSSE may be underrepresented in the literature and occur more frequently than previously thought. Locating a painful soft-tissue mass-like lesion along the path of a previous CS scar is the most indicative sign that should initially alarm physicians towards suggesting CSSE, especially if symptoms are typical (cyclically reoccurring with menstruation). The detection of hyperintense (haemorrhagic) foci on T1 fat-saturated sequences will strongly support the diagnosis on magnetic resonance imaging (MRI), the most sensitive imaging method for CSSE assessment. A non-specific, contrast-enhancing, hypodense nodule with spiculate edges may be suggestive if the lesion was originally detected on computed tomography (CT). Although ultrasound is frequently the first imaging method used, the findings are non-specific; therefore, making it more useful for ruling out other differentials and for image-guided biopsy. In any case, histopathology provides the definitive diagnosis. Surgical excision is the mainstay of treatment; however, minimally invasive, percutaneous techniques have also been implemented successfully.

Multicenter External Validation of the Deep Pelvic Endometriosis Index Magnetic Resonance Imaging Score

Importance

Preoperative mapping of deep pelvic endometriosis (DPE) is crucial as surgery can be complex and the quality of preoperative information is key.

Objective

To evaluate the Deep Pelvic Endometriosis Index (dPEI) magnetic resonance imaging (MRI) score in a multicenter cohort.

Design, Setting, and Participants

In this cohort study, the surgical databases of 7 French referral centers were retrospectively queried for women who underwent surgery and preoperative MRI for DPE between January 1, 2019, and December 31, 2020. Data were analyzed in October 2022.

Intervention

Magnetic resonance imaging scans were reviewed using a dedicated lexicon and classified according to the dPEI score.

Main outcomes and measures

Operating time, hospital stay, Clavien-Dindo-graded postoperative complications, and presence of de novo voiding dysfunction.

Results

The final cohort consisted of 605 women (mean age, 33.3; 95% CI, 32.7-33.8 years). A mild dPEI score was reported in 61.2% (370) of the women, moderate in 25.8% (156), and severe in 13.1% (79). Central endometriosis was described in 93.2% (564) of the women and lateral endometriosis in 31.2% (189). Lateral endometriosis was more frequent in severe (98.7%) vs moderate (48.7%) disease and in moderate vs mild (6.7%) disease according to the dPEI (P < .001). Median operating time (211 minutes) and hospital stay (6 days) were longer in severe DPE than in moderate DPE (operating time, 150 minutes; hospital stay 4 days; P < .001), and in moderate than in mild DPE (operating time; 110 minutes; hospital stay, 3 days; P < .001). Patients with severe disease were 3.6 times more likely to experience severe complications than patients with mild or moderate disease (odds ratio [OR], 3.6; 95% CI, 1.4-8.9; P = .004). They were also more likely to experience postoperative voiding dysfunction (OR, 3.5; 95% CI, 1.6-7.6; P = .001). Interobserver agreement between senior and junior readers was good (κ = 0.76; 95% CI, 0.65-0.86).

Conclusions and Relevance

The findings of this study suggest the ability of the dPEI to predict operating time, hospital stay, postoperative complications, and de novo postoperative voiding dysfunction in a multicenter cohort. The dPEI may help clinicians to better anticipate the extent of DPE and improve clinical management and patient counseling.

Deep pelvic infiltrating endometriosis: MRI consensus lexicon and compartment-based approach from the ENDOVALIRM group

PURPOSE

The purpose of this consensus article was to develop guidelines by a focused panel of experts to elaborate a lexicon of image interpretation, and a standardized region-based reporting of deep infiltrating endometriosis (DIE) with magnetic resonance imaging (MRI).

MATERIALS AND METHODS

Evidence-based data and expert opinion were combined using the RAND-UCLA Appropriateness Method to attain consensus guidelines. Experts scoring of pelvic compartment delineation and reporting template were collected; responses were analyzed and classified as "RECOMMENDED" versus "NOT RECOMMENDED" (when ≥ 80% consensus among experts) or uncertain (when < 80% consensus among experts).

RESULTS

Consensus regarding pelvic compartment delineation and DIE reporting was attained using the RAND-UCLA Appropriateness Method. The pelvis was divided in nine compartments and extrapelvic lesions were assigned to an additional (tenth) compartment. A consensus was also reached for each structure attributed to a compartment and each reporting template item among the experts. No consensus was reached for a normal aspect of uterosacral ligament, but a consensus was reached for an unequivocal involvement leading to a positive diagnosis and an equivocal involvement leading to uncertain diagnosis. Tailored MRI lexicon and standardized region-based report were proposed.

CONCLUSION

These consensus recommendations should be used as a guide for DIE reporting and staging with MRI. Standardized MRI compartment-based structured reporting is recommended to enable consistent accuracy and help select the best therapeutic approach.

Endometriosis: A multimodal imaging review

Endometriosis is a chronic inflammatory disorder characterized endometrial-like tissue present outside of the uterus, affecting approximately 10% of reproductive age women. It is associated with abdomino-pelvic pain, infertility and other non - gynecologic symptoms, making it a challenging diagnosis. Several guidelines have been developed by different international societies to diagnose and classify endometriosis, yet areas of controversy and uncertainty remains. Transvaginal ultrasound (TV-US) is the first-line imaging modality used to identify endometriosis due to its accessibility and cost-efficacy. Enhanced sonographic techniques are emerging as a dedicated technique to evaluate deep infiltrating endometriosis (DIE), depending on the expertise of the sonographer as well as the location of the lesions. MRI is an ideal complementary modality to ultrasonography for pre-operative planning as it allows for a larger field-of-view when required and it has high levels of reproducibility and tolerability. Typically, endometriotic lesions appear hypoechoic on ultrasonography. On MRI, classical features include DIE T2 hypointensity, endometrioma T2 hypointensity and T1 hyperintensity, while superficial peritoneal endometriosis (SPE) is described as a small focus of T1 hyperintensity. Imaging has become a critical tool in the diagnosis, surveillance and surgical planning of endometriosis. This literature review is based mostly on studies from the last two decades and aims to provide a detailed overview of the imaging features of endometriosis as well as the advances and usefulness of different imaging modalities for this condition.

Transvaginal Ultrasound vs. Magnetic Resonance Imaging (MRI) Value in Endometriosis Diagnosis

(1) Background: Endometriosis is a widespread gynecological condition that causes chronic pelvic discomfort, dysmenorrhea, infertility, and impaired quality of life in women of reproductive age. Clinical examination, transvaginal ultrasonography (TVS), and magnetic resonance imaging (MRI) are significant preoperative non-invasive diagnosis procedures for the accurate assessment of endometriosis. Although TVS is used as the primary line for diagnosis, MRI is commonly utilized to achieve a better anatomical overview of the entire pelvic organs. The aim of this systematic review article is to thoroughly summarize the research on various endometriosis diagnosis methods that are less invasive. (2) Methods: To find relevant studies, we examined electronic databases, such as MEDLINE/PubMed, Cochrane, and Google Scholar, choosing 70 papers as references. (3) Results: The findings indicate that various approaches can contribute to diagnosis in different ways, depending on the type of endometriosis. For patients suspected of having deep pelvic endometriosis, transvaginal sonography should be the first line of diagnosis. Endometriosis cysts are better diagnosed with TVS, whereas torus, uterosacral ligaments, intestine, and bladder endometriosis lesions are best diagnosed using MRI. When it comes to detecting intestine or rectal nodules, as well as rectovaginal septum nodules, MRI should be the imaging tool of choice. (4) Conclusions: When diagnosing DE (deep infiltrative endometriosis), the examiner’s experience is the most important criterion to consider. In the diagnosis of endometriosis, expert-guided TVS is more accurate than routine pelvic ultrasound, especially in the deep infiltrative form. For optimal treatment and surgical planning, accurate preoperative deep infiltrative endometriosis diagnosis is essential, especially because it requires a multidisciplinary approach.

T2*-Weighted Imaging Performance in the Detection of Deep Endometriosis among Readers with Different Experience: Comparison with Conventional MRI Sequences

Magnetic resonance imaging (MRI) is an effective technique for the diagnosis and preoperative staging of deep infiltrative endometriosis (DIE). The usefulness of MRI sequences susceptible to chronic blood degradation products, such as T2*-weighted imaging, remains uncertain. The present study aims to evaluate the diagnostic performance of these sequences in addition to the conventional protocol for DIE assessment. Forty-four MRI examinations performed for clinical and/or ultrasound DIE suspicion were evaluated by three readers with variable experience in female imaging. The inter-observer agreement between the reader who analysed only the conventional protocol and the one who also considered T2*-weighted sequences was excellent. The less experienced reader diagnosed a significantly higher number of endometriosis foci on the T2*-weighted sequences compared with the most experienced observer. T2*-weighted sequences do not seem to provide significant added value in the evaluation of DIE, especially in less experienced readers. Furthermore, artifacts caused by undesirable sources of magnetic inhomogeneity may lead to overdiagnosis.

Spiders and mushrooms: Reporting bowel endometriosis shape on preoperative MRI to flag surgical complexity

INTRODUCTION

Preoperative imaging of patients with endometriosis allows adequate counselling, referral to appropriate centres of expertise and workforce planning. The objective of this study was to assess the feasibility of simplified three-category preoperative endometriosis MRI morphological descriptors to predict subsequent surgical management.

METHODS

A single-centre observational study in 76 patients (median age 38 years, range 18-55) with preoperative endometriosis mapping MRI between 1 Jan 2015 and 31 Dec 2019. MRI studies were prospectively re-read blind-to-surgical outcome to categorise rectosigmoid morphology as normal, spider-shaped (linear T2-dark fibrotic bands) superficial endometriosis or typical crescentic or mushroom-shaped deep infiltrating endometriosis (DIE). Bowel motility was similarly categorised as normal, tethered or distorted/fixed. The reference standard was subsequent surgery within 3 years of MRI, categorised as no bowel surgery, adhesiolysis only or more complex surgeries.

RESULTS

Despite three-quarters of surgical cases having normal bowel morphology on preoperative MRI (72%, 55/76; 12% linear superficial endometriosis, 10% crescentic and 5% mushroom-shaped DIE) more than half showed bowel tethering (54%, 41/76) or distortion/fixation (10%, 8/76) and most patients underwent adhesiolysis (79%, 60/76). Complex surgery such as bowel resection, laparotomy conversion or complex adhesiolysis is predicted by morphology (crescentic or mushroom-shaped DIE, P < 0.001) and motility (tethered or distorted bowel, P = 0.002) descriptors.

CONCLUSIONS

Comprehensive and clinically relevant diagnostic reporting does not have to be convoluted to have clinical impact: in our study population, categorising bowel morphology as normal, spider-shaped (superficial) or crescentic/mushroom-(DIE) shaped and motility as normal, tethered (superficial) or distorted/fixed (deep endometriosis) correlates to subsequent surgical complexity.

MRI in the Diagnosis of Endometriosis and Related Diseases

Endometriosis, a common chronic inflammatory disease in female of reproductive age, is closely related to patient symptoms and fertility. Because of its high contrast resolution and objectivity, MRI can contribute to the early and accurate diagnosis of ovarian endometriotic cysts and deeply infiltrating endometriosis without the need for any invasive procedure or radiation exposure. The ovaries, which are the most frequent site of endometriosis, can be afflicted by multiple related conditions and diseases. For the diagnosis of deeply infiltrating endometriosis and secondary adhesions among pelvic organs, fibrosis around the ectopic endometrial gland is usually found as a T2 hypointense lesion. This review summarizes the MRI findings obtained for ovarian endometriotic cysts and their physiologically and pathologically related conditions. This article also includes the key imaging findings of deeply infiltrating endometriosis.

Indirect and atypical imaging signals of endometriosis: A wide range of manifestations

Background

Whilst some imaging signs of endometriosis are common and widely accepted as ‘typical’, a range of ‘subtle’ signs could be present in imaging studies, presenting an opportunity to the radiologist and the surgeon to aid the diagnosis and facilitate preoperative surgical planning.

Objective

To summarise and analyse the current information related to indirect and atypical signs of endometriosis by ultrasound (US) and magnetic resonance imaging (MRI).

Methods

Through the use of PubMed and Google scholar, we conducted a comprehensive review of available articles related to the diagnosis of indirect signs in transvaginal US and MRI. All abstracts were assessed and the studies were finally selected by two authors.

Results

Transvaginal US is a real time dynamic exploration, that can reach a sensitivity of 79-94% and specificity of 94%. It allows evaluation of normal sliding between structures in different compartments, searching for adhesions or fibrosis.

MRI is an excellent tool that can reach a sensitivity of 94% and specificity of 77% and allows visualisation of the uterus, bowel loop deviation and peritoneal inclusion cysts. It also allows the categorisation and classification of ovarian cysts, rectovaginal and vesicovaginal septum obliteration, and small bowel endometriotic implants.

Conclusion

The use of an adequate mapping protocol with systematic evaluation and the reporting of direct and indirect signs of endometriosis is crucial for detailed and safe surgical planning.

Imaging of acute pelvic pain

Acute pelvic pain (APP) requires urgent medical evaluation and treatment. Differential diagnosis of APP is broad, including a variety of gynecologic and non-gynecologic/ urinary, gastrointestinal, vascular and other entities. Close anatomical and physiological relations of pelvic structures, together with similar clinical presentation of different disorders and overlapping of symptoms, especially in the emergency background, make the proper diagnosis of APP challenging. Imaging plays a crucial role in the fast and precise diagnosis of APP. Ultrasonography is the first-line imaging modality, often accompanied by CT, while MRI is utilized in specific cases, using short, tailored protocols. Recognizing the cause of APP in females is a challenging task, due to the wide spectrum of possible origin and overlap of their imaging features. Therefore, the radiologist has to be familiar with the possible causes of APP, and, relying on clinical presentation, together with laboratory findings, choose the best imaging strategy in order to establish a fast and accurate diagnosis.

Müllerian Duct Anomalies: Role in Fertility and Pregnancy

Müllerian duct anomalies (MDAs) have important implications for the reproductive health of female patients. In patients with both infertility and recurrent pregnancy loss, the incidence of MDAs is as high as 25%. Congenital uterine anomalies are often only part of a complex set of congenital anomalies involving the cervix, vagina, and urinary tract. Multiple classification systems for MDAs exist, each with different criteria that vary most for the diagnosis of septate uterus. Recognizing the features that guide clinical management is essential for interpretation. Identification of an MDA should prompt evaluation for associated urinary tract anomalies. In patients with infertility who seek to use assisted reproductive technologies such as intrauterine insemination, recognition of MDAs may have an affect on reproductive success, particularly in patients who have an incomplete and clinically occult septum that divides the cervix. Two-dimensional US is the first-line modality for evaluating the uterus and adnexa. Three-dimensional (3D) US or MRI may help to visualize the external uterine fundal contour and internal indentation of the endometrial cavity, which are two morphologic characteristics that are keys to the diagnosis of congenital uterine anomalies. Hysterosalpingo contrast-enhanced US may be performed in conjunction with 3D US to evaluate uterine morphologic characteristics, the endometrial cavity, and tubal patency in a single examination. MRI helps to characterize rudimentary uteri in patients with müllerian hypoplasia and allows assessment for ectopic ureters, abnormally positioned ovaries, or associated deep infiltrative endometriosis. Online supplemental material is available for this article. ©RSNA, 2021.

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.

Magnetic resonance imaging for deep infiltrating endometriosis: current concepts, imaging technique and key findings

Endometriosis is an estrogen-dependent chronic disease affecting about 10% of reproductive-age women with symptoms like pelvic pain and infertility. Pathologically, it is defined by the presence of endometrial tissue outside the uterine cavity responsible for a chronic inflammatory process. For decades the diagnosis of endometriosis was based on surgical exploration and biopsy of pelvic lesions. However, laparoscopy is not a risk-free procedure with possible false negative diagnosis due to an underestimate of retroperitoneal structures such as ureters and nerves. For these reasons nowadays, the diagnosis of endometriosis is based on a noninvasive approach where clinical history, response to therapy and imaging play a fundamental role. Trans-vaginal ultrasound and magnetic resonance imaging are suitable for recognizing most of endometriotic lesions; nevertheless, their accuracy is strictly determined by operators’ experience and imaging technique. This review paper aims to make radiologists aware of the diagnostic possibilities of pelvic MRI and familial with the MR acquisition protocols and image interpretation for women with endometriosis.

Magnetic Resonance Imaging in the Evaluation of Female Infertility

Pelvic MRI plays an important adjunctive role in the clinical workup of female infertility. Hysterosalpingography is the first line imaging modality in evaluation of female infertility, and hysterosalpingo-contrast sonography can also be used to evaluate both the uterine cavity and fallopian tubes. Pelvic MRI can be helpful in the workup of female infertility, particularly in cases of Mullerian duct anomalies, fibroids, adenomyosis, endometriosis, and tubal disease. These conditions and their appearance on imaging will be reviewed in this article.

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.

Transvaginal Sonographic Imaging and Associated Techniques for Diagnosis of Ovarian, Deep Endometriosis, and Adenomyosis: A Comprehensive Review

Imaging of endometriosis and in particular deep endometriosis (DE) is crucial in the clinical management of women facing this debilitating condition. Transvaginal sonography (TVS) is the first-line imaging method and magnetic resonance imaging (MRI) may provide supplemental information. However, the delay in diagnosis of up to 10 years and more is of concern. This problem might be overcome by simple steps using imaging with emphasis on TVS and referral to tertiary care. Finally, TVS is crucial in mapping extent and location of disease in planning surgical therapy and counseling women regarding various therapeutic options. This review presents the available data on imaging of endometriosis with a focus on TVS and MRI for DE, adenomyosis, and ovarian endometriomas including endometriomas in pregnancy as well as the use of "soft markers." The review presents an approach that is in accordance with the International Deep Endometriosis Analysis (IDEA) group consensus statement.