Sonographic Evaluation for Endometriosis in Routine Pelvic Ultrasound.

Study Objective: To show how the evaluation for endometriosis can be included in the routine pelvic ultrasound examination.

Design: Stepwise narrated video demonstration of the sonographic evaluation for endometriosis in routine pelvic ultrasound following the recommended sonographic approach published in the 2016 consensus paper by the International Deep Endometriosis Analysis (IDEA) group [1].

Setting: Endometriosis is a common and often debilitating gynecological disorder that affects 5-10% of women [2]. The prevalence is even higher among women with symptoms of endometriosis [2], which include chronic pelvic pain, acquired dysmenorrhea, dyspareunia, dyschezia, menorrhagia, abnormal bleeding, and infertility. Approximately 80% of women who have endometriosis have superficial lesions, whereas 20% have deep infiltrating endometriosis (DIE; [3]). Laparoscopy is the gold standard for diagnosing endometriosis, because it allows the diagnosis of all forms of endometriosis and often immediate removal of superficial endometriosis. The removal of DIE is considerably more complicated and usually cannot be completed unless it was diagnosed preoperatively. The technique to diagnose DIE with transvaginal ultrasound (TVUS) was first described in detail in 2009 [4]. Since then, the accuracy of TVUS for the prediction of DIE has been well established in the literature [5-7]. TVUS is widely used as a first-line investigation for women with gynecological symptoms. The inclusion of an assessment for endometriosis in the routine pelvic ultrasound allows earlier diagnosis and better surgical outcomes for all women with DIE.

Interventions: The evaluation for endometriosis in routine pelvic ultrasound based on the IDEA consensus promotes a 4-step dynamic ultrasound approach [1]: (1) routine evaluation of uterus and adnexa with particular attention for sonographic signs of adenomyosis and the presence or absence of endometriomas; (2) evaluation of transvaginal sonographic 'soft markers' such as site-specific tenderness and ovarian mobility; (3) assessment of status of pouch of Douglas using the real-time ultrasound-based "sliding sign;" and (4) assessment of DIE nodules in the anterior and posterior compartments, which involves assessment of the bladder, vaginal vault, uterosacral ligaments, and bowel, including rectum, rectosigmoid junction, and sigmoid colon. Because 5-10% of women with DIE also have ureteric endometriosis, it is useful to assess the kidneys. Silent hydronephrosis is easily identified in 50-60% of patients with ureteric involvement. Although it is possible to identify DIE involving the ureters more directly, this requires more advanced skills, and further studies are still needed to better define the accuracy of ureteric DIE detection by TVUS [8-10].

Conclusion: Traditionally, only pathologies of the uterus and ovaries are assessed during a routine pelvic ultrasound. Here we demonstrate that the routine ultrasound examination can easily be extended beyond the uterus and ovaries into the posterior and anterior pelvic compartments to evaluate structural mobility and to look for deep infiltrating endometriotic nodules, wherewith women suffering from DIE can benefit from a preoperative diagnosis and subsequently, a single, well-planned procedure in the hands of a well-prepared team.