Abstract:

Objective

To investigate the diagnostic efficacy of transperineal ultrasound in detecting the morphology and function of the levator ani muscle in patients with pelvic organ prolapse （POP）.

Methods

The clinical and ultrasonographic data of 100 POP patients and 100 non-POP patients from the Xiangya Hospital of Central South University from October 2023 to May 2024 were retrospectively analyzed in this study. In resting and maximal Valsalva state， three-dimensional transperineal ultrasound was used to measure the anteroposterior and left-to-right diameters and area of levator ani hiatus in real time. The integrity of the levator ani muscle was assessed during pelvic floor muscle contraction， and the levator-urethra gap for both sides was measured. Independent sample t-test was used to compare the differences in measurements of anal sphincter hiatus between groups， and Chi-square test was used to compare the differences in rates of anal sphincter injury between groups.

Results

In the resting state， the anteroposterior and left-toright diameters， and area of levator ani hiatus in the study group were significantly higher than those of the control group ［（57.6±4.1） mm vs （53.2±4.7） mm， （47.7±4.4） mm vs （40.8±4.1） mm， and （18.12±2.15） cm² vs （14.87±2.63） cm²； t=6.922， 11.275， and 9.383， respectively； P＜0.001 for all］. In maximum Valsalva state， the anteroposterior and left-to-right diameters and area of levator ani hiatus in the study group were also significantly higher than those of the control group ［（63.4±3.1） mm vs （53.5±3.2） mm， （51.3±4.7） mm vs （40.2±3.0） mm， and （22.27±2.65） cm² vs （16.46±2.7） cm²； t=21.820， 19.618， and 15.053， respectively；P＜0.001 for all］. Assessing the contraction status of pelvic floor muscles showed that the injury rate of the levator ani muscle in the study group was 22.1%， which significantly higher than that of the control group （3.1%；χ²=16.067， P＜0.001）. The left and right levator-urethra gaps in the study group were significantly higher than those in the control group ［（23.92±3.87） mm vs （18.14±2.75） mm and （24.76±3.62） mm vs （18.72±2.76） mm； t=11.989 and 13.060， respectively； P＜0.001 for both］.

Conclusion

Three-dimensional and real-time three-dimensional transperineal ultrasound combined with tomographic ultrasound imaging can effectively assess the morphological changes and the functional status of levator ani muscles， which has high diagnostic value for POP.

Key words: Pelvic organ prolapse, Levator ani muscle, Tomography, Three-dimensional imaging