Abstract
Endometriosis is a condition in which functional endometrial glands are located outside the uterine cavity. Common sites are the pelvic peritoneum, the ovaries, uterine ligaments and rectovaginal septum.
Endometriosis
Endometriosis is a condition in which functional endometrial glands are located outside the uterine cavity. Common sites are the pelvic peritoneum, the ovaries, uterine ligaments and rectovaginal septum.
Abdominal pain coincides with menstruation as the glands respond to ovarian hormones, causing bleeding. Recurrent haemorrhage is followed by scarring and the formation of fibrous adhesions, distorting the ovaries and fallopian tubes, which may be a cause of infertility.
Small endometrial implants are too small to be imaged with vaginal sonography; however larger, localised endometriomas or ‘chocolate cysts’ can be detected with pelvic ultrasound.
Endometriomas on transvaginal scans appear as a unilocular or multilocular mass containing diffuse uniform echoes throughout (ground glass appearance), mildly thickened walls and acoustic enhancement. No vascularity is demonstrated inside the cyst using colour Doppler. A similar appearance may be seen with haemorrhagic cysts; however, these will resolve or decrease in size during the ensuing one or two menstrual cycles.
Endometriosis can infiltrate into the uterosacral ligaments, bowel, bladder and the vagina. Adhesions will cause the organs to be stuck together and the uterus and ovaries will not slide along the adjacent structures. This can be demonstrated by applying pressure on the uterus and ovaries and seeing the sliding movement of the structures against the adjacent tissues or alternately, by applying pressure on the abdomen above the symphysis pubis. These actions will elicit pain when pushing with the probe.
Figure 5.1 Endometrioma in the left ovary with follicle.
Figure 5.2 Endometriosis in the ovary with multiple follicles.
Figure 5.3 Endometriotic cyst in the ovary which is hypoechoic and has an irregular outline.
Figure 5.4 Multiple endometriotic cysts in the ovary.
Figure 5.5 Large endometrioma seen as a hypoechoic lesion.
