Transvaginal ultrasound features of normal uterosacral ligaments

Abstract

Objective: To show a step-by-step technique to assess normal uterosacral ligaments (USLs) during transvaginal ultrasound. Uterosacral ligaments represent the most common location of deep infiltrating endometriosis (DIE) in the posterior compartment and their involvement significantly increases the risk of ureteral lesions. The ultrasonographic diagnosis of DIE involving USLs is characterized by a wide range of accuracies described between studies, probably due to variations in the examination technique, quality of ultrasound equipment, and experience of the operators. Although described as a new classification system of DIE involving USLs, the technique for visualizing normal USLs has not yet been described.

Design: Stepwise demonstration of the technique with narrated video footage.

Setting: Academic tertiary hospital.

Patient(s): The video shows a 33-year-old nulliparous woman scheduled for laparoscopic removal of a para-ovarian cyst of approximately 6 cm. Procedural steps were repeated and confirmed in another four patients submitted to laparoscopy for benign diseases (Table 1). Moreover, we here show the case of a 29-year-old woman with an isolated DIE nodule of the right USL with a comparison of laparoscopic and ultrasound findings. To better point out the technique applied in a clinical setting we show also cases of infiltrated USLs (Table 2) during the ultrasound scan in women scheduled for endometriosis surgery. Informed consent was obtained from all of the patients. The study protocol was approved by the local institutional Ethics Committee (580/2018/Oss/AOUBo).

Intervention(s): To understand correctly the right position of USLs we performed an ultrasound during a surgical procedure; in this way it was possible to recognize the area of interest while the surgeon filled the pouch of Douglas with fluid and highlighted the anatomical area with pliers. Uterosacral ligaments can be seen in the mid-sagittal and transverse view of the uterus.

Main outcome measure(s): Description of appearance of normal USLs during transvaginal ultrasound.

Result(s): Uterosacral ligaments, at transvaginal ultrasound, appear as hyperechoic stripes starting from the cervix and pointing laterally in a semi-horizontal direction.

Conclusion(s): We provided a step-by-step technique (Table 3) that may be a useful tool to see accurately both the USLs at transvaginal ultrasound.

Keywords: Uterosacral ligament; step by step; ultrasound; video.