Transvaginal sonography for predicting the distance between rectosigmoid endometriosis and the anal verge

Transvaginal ultrasonography is important in the evaluation of patients with rectosigmoid deep endometriosis.

Key Points

Highlights:

• Transvaginal sonography is a feasible technique for measuring the distance between rectosigmoid endometriosis lesions and the anal verge "Lesion to Anal Verge Distance-LAVD" before surgery.

Importance:

• The authors suggested that transvaginal sonography (TVUS) can be useful in predicting the anastomosis height pre-operatively.
• Age, symptoms, severity of the disease, and fertility issues determine the extent of deep endometriosis surgery in each patient.

What's done here:

• The researchers analyzed the accuracy of transvaginal sonography in the pre-surgical measurement of the LAVD compared to intraoperative in vivo measurement.

Key Results:

• Neither clinically nor statistically significant difference observed between the use of TVUS or intraoperative in vivo measurement for defining the LAVD.
• The reliability between the transvaginal sonography and intraoperative in vivo measurements of the LAVD was good.
• Shorter LAVD poses an increased risk of complications such as anastomotic leakage and rectovaginal fistula if treated surgically since they are usually attached to surrounding pelvic structures pulling the lesion closer to the anal verge.
• Transvaginal sonography is a cost-effective, non-invasive tool that accurately evaluates rectosigmoid endometriosis lesion height before surgery.

Limitations:

• One person from each study center performed both measuring methods.
• There may be an interobserver bias since this is a multi-center study with three gynecologists performing transvaginal sonography.

Lay Summary

For optimal surgery, pre-surgical assessment of the distance between rectosigmoid deep endometriosis lesions and the anal verge (Lesion to Anal Verge Distance-LAVD) is recommended by many specialists. A group of researchers from Norway, Austria, and Australia studied the accuracy of transvaginal sonography in the pre-surgical measurement of the LAVD compared to intraoperative in vivo measurement. This paper has recently been published in the journal "Ultrasound in Obstetrics & Gynecology".

The present study included 133 symptomatic rectosigmoid endometriosis patients who were consecutively scheduled for elective surgery. Segmental resection discoid resection or both procedures were performed in 102, 34, 3 patients, respectively.

Aas-Eng MK et al. found a good agreement between the measuring methods in 13.0% of women. In 48.1% of women, transvaginal sonography measured lower than intraoperative in vivo measurement and measured higher than intraoperative in vivo measurement in 38.9% women. The mean measurement using transvaginal sonography was 114.8 mm (SD = 36.5) and intraoperative in vivo measurement was 116.9 mm (SD = 42.3).

Overall, transvaginal sonography tended to measure lower than intraoperative in vivo measurement. However, this difference was neither statistically nor clinically significant. The authors explained that this difference results from the difference between detached rectosigmoid deep endometriosis lesions from the surrounding organs and fixed rectosigmoid deep endometriosis to adjacent structures.

The authors stated that their research is the first study to demonstrate good reliability between the transvaginal sonography and intraoperative in vivo measurements of the LAVD.

According to the team’s observations, transvaginal sonography is useful for measuring LAVD of rectosigmoid deep endometriosis. This pre-measurement helps in estimating the height of the bowel anastomosis and the risk of complications in patients undergoing surgery. The authors stress the necessity of transvaginal ultrasonography in the evaluation of patients with rectosigmoid deep endometriosis.

Research Source: https://pubmed.ncbi.nlm.nih.gov/32068921