Normal uterosacral ligament and rectouterine pouch peritoneum

The beginning of the clip depicts a thin hyperechoic layer just deep to the vagina, which represents the rectouterine pouch peritoneum. To find the uterosacral ligaments, it is best to start with this view (generally the probe is exactly midline within the posterior vaginal fornix and aimed posteriorly). Once the peritoneum is in view, sweep the hand to one side and slightly angle the probe (clockwise for the right uterosacral ligament and counter-clockwise for the left uterosacral ligament). Thickening of the hyperechoic layer represents the uterosacral ligament. If vessels begin to appear, the probe is too lateral and should be brought back medially.

For more information: Noninvasive ultrasound diagnosis of endometriosis