Imaging for the evaluation of endometriosis and adenomyosis

Endometriosis affects between 5 and 45% of women in reproductive age, is associated with significant morbidity, and constitutes a major public health concern. The correct diagnosis is fundamental in defining the best treatment strategy for endometriosis. Therefore, non-invasive methods are required to obtain accurate diagnoses of the location and extent of endometriotic lesions. Transvaginal sonography and magnetic resonance imaging are used most frequently to identify and characterise lesions in endometriosis. Subjective impression by an experienced sonologist for identifying endometriomas by ultrasound showed a high accuracy. Adhesions can be evaluated by real-time dynamic transvaginal sonography, using the sliding sign technique, to determine whether the uterus and ovaries glide freely over the posterior and anterior organs and tissues. Diagnosis is difficult when ovarian endometriomas are absent and endometriosis causes adhesions and deep infiltrating nodules in the pelvic organs. Magnetic resonance imaging seems to be useful in diagnosing all locations of endometriosis, and its diagnostic accuracy is similar to those obtained using ultrasound. Transvaginal ultrasound has been proposed as first line-line imaging technique because it is well accepted and widely available. The main limitation of ultrasound concerns lesions located above the rectosigmoid junction owing to the limited field-of-view of the transvaginal approach and low accuracy in detecting upper bowel lesions by transabdominal ultrasound. A detailed non-invasive diagnosis of the extension in the pelvis of endometriosis can facilitate the choice of a safe and adequate surgical or medical treatment.