Ultrasound findings in endometriosis: avoid hidden surprises

OBJECTIVE: To discuss the steps to performing and interpreting ultrasound imaging for pelvic pain in women with suspicions of endometriosis. DESIGN: Educational video. SETTING: Specialized gynecologic ultrasound clinic. PATIENTS: Reproductive-age women with pelvic pain with findings suggestive of endometriosis. INTERVENTION: Transvaginal ultrasound imaging. MAIN OUTCOME MEASURES: A detailed discussion of findings suggesting endometriosis. RESULTS: There are four basic sonographic steps for examining women with pelvic pain, especially when there is suspicion of endometriosis. Step 1: routine evaluation of the uterus and adnexa (this includes uterine orientation, sonographic signs of adenomyosis, and the presence or absence of endometrioma). Step 2: evaluation of transvaginal sonographic markers for endometriosis, for example, site-specific tenderness and ovarian mobility. Step 3: assessment of anterior and posterior compartments using a real-time ultrasound-based "sliding sign"; and Step 4: assessment for deep endometriotic nodules in anterior and posterior compartments. Note: the bladder should contain a small amount of urine for anterior compartment evaluation. CONCLUSIONS: Ultrasound is a powerful and dynamic tool for evaluating pelvic pain with high sensitivity, specificity, and accuracy in diagnosing deep endometriosis. Ultrasound imaging is important not only for diagnosing but also to counsel patients properly, consent appropriately, and plan for interdisciplinary consultations.