Dynamic transvaginal ultrasound examination for assessing anatomy of parametrium

Data available on request from the authors We start by inserting the probe into the vaginal introitus. On the right of the screen, we can identify the urethra and the bladder with some fluid; in the center is the vaginal wall and on the left the rectum. Then, we gently advance the probe to the anterior vaginal fornix and we can visualize the cervix, in a sagittal section. We identify here the anterior and posterior lips of the cervix, and the internal and external uterine ora. Moving the probe cranially, we can visualize the uterus and the endometrium. The vesicovaginal septum can be evaluated by pushing the vagina and uterus against the bladder. Then, moving the probe from the mid- sagittal section to the lateral sagittal section we can visualize the terminal part of the ureter next to the bladder and assess the hyperechoic tissue surrounding the terminal part of the ureter corresponding to vesicovaginal (caudal to the ureter) and vesicouterine (cranial to the ureter) ligaments. We can repeat the procedure on the other side to visualize the contralateral structures. Subsequently, moving the probe laterally, we can visualize the ureter and the crossing point of the uterine vessels, then we can rotate the probe 90° at the level of the crossing point: in this transverse section we can visualize the cervix, vagina, ureter and pelvic wall. The region between cervix and pelvic wall (with the ureter in the middle) corresponds to the paracervix/paracolpium and parauterine lymphovascular tissue. To assess the dorsal compartment, we return the probe to the anterior vaginal fornix. From a mid-sagittal section of the cervix, we can recognize the vaginal wall, the vagina fornix, the uterine torus, and the retrocervix. Then, in a sagittal section, we can slowly lateralize the probe to assess the posterior hyperechoic tissue surrounding the cervix (corresponding to the “uterosacral or sacrouterine ligament”). We can then repeat the same movements on the other side, to assess the same structures. Finally, we sweep the probe 90° clockwise and, by moving the probe craniocaudally, we can assess the “uterosacral or sacrouterine ligaments” and more caudally, the rectovaginal ligaments in a transverse plan. The “uterosacral or sacrouterine ligament” can be also assessed positioning the probe in the posterior vaginal fornix, exerting pressure against the hyperechoic tissue in a semihorizontal direction. Finally, in the midsagittal section we can visualize the rectovaginal septum by pushing the probe against the rectum and vagina. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.