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

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

REVIEWED BY Jessica Coffey | ASA SIG: Women’s Health

REFERENCE | Authors: Condous G, Gerges B, Thomassin-Naggara I, Becker C, Tomassetti C, Krentel H, van Herendael BJ, Malzoni M, Abrao MS, Saridogan E, Keckstein J, Hudelist G and Collaborators

WHY THE STUDY WAS PERFORMED

Endometriosis affects a significant proportion of women globally and accurate and timely noninvasive diagnosis is pivotal for patient counselling and planning of treatment strategies. This is particularly important in cases of deep endometriosis (DE), which is observed in 20% of patients with endometriosis. Presurgical diagnosis of DE can assist in surgical planning, prediction of operative difficulty, and in the context of infertility provide aid in decisions around treatment and assisted reproductive technologies. The performance of noninvasive imaging techniques such as transvaginal ultrasound (TVS), MRI and CT, as well as various proposed classification systems, have been heavily studied over the last two decades. This consensus statement was developed by ISUOG, IDEA, ESGE, EEL, ISGE, ESHRE, ESUR and AAGL to develop evidence-based and clinically relevant statements to guide the use of noninvasive imaging techniques for the diagnosis and classification of pelvic DE.

Transvaginal ultrasound is recommended as a first-line imaging tool due to its availability, good test performance, cost efficacy and low environmental impact.

HOW THE STUDY WAS PERFORMED

The consensus statement was developed using a six-step protocol chaired and organised by professors George Condous (GC) and Gernot Hudelist (GH). An international, multidisciplinary working group was established, consisting of chairs of each society and including expert gynaecological surgeons, sonographers and radiologists. A systemic literature review of relevant studies published from inception to February 2023 was carried out by coordinating chairs and Bassem Gerges (BG). This search was limited to publications in English and excluded editorials, letters and case reports. From this literature review, GC, GH and BG formulated preliminary consensus statements which were then distributed to society chairs for first-round revisions. Statements were then modified, and the process was repeated. Society group members then voted in a binary fashion on the finalised statements.

WHAT THE STUDY FOUND

The finalised 20 statements included general statements, statements on ultrasonography, statements on MRI and CT and statements on the noninvasive use of classification systems. Of these, 14 received strong agreement (> 80%), 3 moderate agreement (60–80%) and 1 remained equipoise (40–60%). There was strong agreement that TVS can accurately determine or rule out DE affecting the rectum, rectovaginal septum and bladder. However, its performance in assessing DE affecting other locations, such as the parametrium and uterosacral ligaments (USL) was less sensitive. There was consensus that MRI can more reliably predict the presence of DE in these locations. The working group found the use of classification systems a matter of ongoing debate. The majority of participants agreed on the use of TVS or MRI in combination with the #Enzian classification, with the acknowledgement that it was found to be less accurate in cases of parametrial and USL involvement.

RELEVANCE TO CLINICAL PRACTICE

These statements advocate the use of TVS as a first-line imaging tool due to its availability, good test performance, cost efficacy and low environmental impact. They highlight the limitations of both TVS and MRI in the assessment of DE in specific locations and help provide a guideline for appropriate imaging modalities. These statements also highlight the need for standardisation of the classification system used in the diagnosis of DE, with the strongest agreement and level of evidence for the use of the #Enzian system. They also emphasise that imaging test performance is operator-dependent and will increase with exposure, level of training and skill of the operator.