The female pelvic floor (PF) muscles provide support to the pelvic organs. During delivery, some of these muscles have to stretch up to three times their original length to allow passage of the baby, leading frequently to damage and consequently later-life PF dysfunction (PFD). Three-dimensional (3D) ultrasound (US) imaging can be used to image these muscles and to diagnose the damage by assessing quantitative, geometric and functional information of the muscles through strain imaging. In this study we developed 3D US strain imaging of the PF muscles and explored its application to the puborectalis muscle (PRM), which is one of the major PF muscles.

KEYWORDS: 3D/4D ultrasound; pelvic floor; translabial ultrasound; vaginal laxity CONTRIBUTION What are the novel findings of this work? Our results show a clear, statistically significant increase in measures of pelvic floor distensibility in women complaining of vaginal laxity, supporting the growing evidence of an association between vaginal laxity and pelvic floor hyperdistensibility, and contributing to a method for objectively defining this condition. What are the clinical implications of this work?Since vaginal laxity is likely to be under-reported by patients, and given its association with pelvic floor hyperdistensibility, gynecologists should be sure to investigate sexual function, especially in women with a clinically wide hiatus or hiatal 'ballooning' on translabial ultrasound. ABSTRACT Objective To assess the predictive value of measures of levator hiatal distension at rest and on maximum Valsalva maneuver for symptoms of vaginal laxity.Methods This was a retrospective study of women seen at a tertiary urogynecological unit. All women underwent a standardized interview, clinical examination and four-dimensional translabial ultrasound examination. Area, anteroposterior diameter (APD) and coronal diameter (CD) of the levator hiatus were measured at rest and on maximum Valsalva maneuver in the plane of minimal hiatal dimensions using the rendered volume technique, by an operator blinded to all clinical data. The association between levator hiatal measurements and vaginal laxity was assessed, and receiver-operating-characteristics (ROC)-curve analysis was used to determine their predictive value.Results Data from 490 patients were analyzed. Mean age was 58 (range, 18-88) years, and vaginal laxity was reported by 111 (23%) women. Measurements obtained on maximum Valsalva were significantly larger in women who reported vaginal laxity than in those who did not, with mean levator hiatal area, APD and CD of 30.45 ± 8.74 cm 2 , 7.24 ± 1.16 cm and 5.60 ± 0.89 cm, respectively, compared with 24.84 ± 8.63 cm 2 , 6.64 ± 1.22 cm and 5.01 ± 0.97 cm in the no-laxity group (P < 0.001 for all). Measurements obtained at rest were not significantly different between the groups. Multiple logistic regression analysis controlling for age, body mass index, vaginal parity and levator avulsion confirmed these results. The best regression model for the prediction of vaginal laxity included age, vaginal parity and levator hiatal area on maximum Valsalva. ROC-curve analysis of levator hiatal measurements on maximum Valsalva in the prediction of vaginal laxity demonstrated areas under the curve of 0.68 (95% CI, 0.63-0.73) for area, 0.63 (95% CI, 0.57-0.68) for APD and 0.68 (95% CI, 0.62-0.73) for CD.Conclusions Levator hiatal area on maximum Valsalva seems to be the measure of levator ani distensibility that is most predictive of symptoms of vaginal laxity. Copyright

Objective To develop and validate a tool for automatic selection of the slice of minimal hiatal dimensions (SMHD) and segmentation of the urogenital hiatus (UH) in transperineal ultrasound (TPUS) volumes. Methods Manual selection of the SMHD and segmentation of the UH was performed in TPUS volumes of 116 women with symptomatic pelvic organ prolapse (POP). These data were used to train two deep‐learning algorithms. The first algorithm was trained to provide an estimation of the position of the SMHD. Based on this estimation, a slice was selected and fed into the second algorithm, which performed automatic segmentation of the UH. From this segmentation, measurements of the UH area (UHA), anteroposterior diameter (APD) and coronal diameter (CD) were computed automatically. The mean absolute distance between manually and automatically selected SMHD, the overlap (dice similarity index (DSI)) between manual and automatic UH segmentation and the intraclass correlation coefficient (ICC) between manual and automatic UH measurements were assessed on a test set of 30 TPUS volumes. Results The mean absolute distance between manually and automatically selected SMHD was 0.20 cm. All DSI values between manual and automatic UH segmentations were above 0.85. The ICC values between manual and automatic UH measurements were 0.94 (95% CI, 0.87–0.97) for UHA, 0.92 (95% CI, 0.78–0.97) for APD and 0.82 (95% CI, 0.66–0.91) for CD, demonstrating excellent agreement. Conclusions Our deep‐learning algorithms allowed reliable automatic selection of the SMHD and UH segmentation in TPUS volumes of women with symptomatic POP. These algorithms can be implemented in the software of TPUS machines, thus reducing clinical analysis time and simplifying the examination of TPUS data for research and clinical purposes. © 2021 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Background The levator ani muscle (LAM) consists of different subdivisions, which play a specific role in the pelvic floor mechanics. The aim of this study is to identify and describe the appearance of these subdivisions on 3-Dimensional (3D) transperineal ultrasound (TPUS). To do so, a study designed in three phases was performed in which twenty 3D TPUS scans of vaginally nulliparous women were assessed. The first phase was aimed at getting acquainted with the anatomy of the LAM subdivisions and its appearance on TPUS: relevant literature was consulted, and the TPUS scan of one patient was analyzed to identify the puborectal, iliococcygeal, puboperineal, pubovaginal, and puboanal muscle. In the second phase, the five LAM subdivisions and the pubic bone and external sphincter, used as reference structures, were manually segmented in volume data obtained from five nulliparous women at rest. In the third phase, intra- and inter-observer reproducibility were assessed on twenty TPUS scans by measuring the Dice Similarity Index (DSI). Results The mean inter-observer and median intra-observer DSI values (with interquartile range) were: puborectal 0.83 (0.13)/0.83 (0.10), puboanal 0.70 (0.16)/0.79 (0.09), iliococcygeal 0.73 (0.14)/0.79 (0.10), puboperineal 0.63 (0.25)/0.75 (0.22), pubovaginal muscle 0.62 (0.22)/0.71 (0.16), and the external sphincter 0.81 (0.12)/0.89 (0.03). Conclusion Our results show that the LAM subdivisions of nulliparous women can be reproducibly identified on 3D TPUS data.

Objectives To clarify which parameters are associated with unsuccessful pessary fitting for pelvic organ prolapse (POP) at up to 3 months follow-up. Methods Embase, PubMed and Cochrane CENTRAL library were searched in May 2020. Inclusion criteria were: (1) pessary fitting attempted in women with symptomatic POP; (2) pessary fitting success among the study outcomes with a maximal follow-up of 3 months; (3) baseline parameters compared between successful and unsuccessful group. A meta-analysis was performed using the random effects model. Main results Twenty-four studies were included in the meta-analysis. Parameters associated with unsuccessful pessary fitting were: age (OR 0.70, 95% CI 0.56–0.86); BMI (OR 1.35, 95% CI 1.08–1.70); menopause (OR 0.65 95% CI 0.47–0.88); de novo stress urinary incontinence (OR 5.59, 95% CI 2.24–13.99); prior surgery, i.e. hysterectomy (OR 1.88, 95% CI 1.48–2.40), POP surgery (OR 2.13, 95% CI 1.34–3.38), pelvic surgery (OR 1.81, 05% CI 1.01–3.26) and incontinence surgery (OR 1.87, 95% CI 1.08–3.25); Colorectal-Anal Distress Inventory-8 scores (OR 1.92, 95% CI 1.22–3.02); solitary predominant posterior compartment POP (OR 1.59, 95% CI 1.08–2.35); total vaginal length (OR 0.56, 95% CI 0.32–0.97); wide introitus (OR 4.85, 95% CI 1.60–14.68); levator ani avulsion (OR 2.47, 95% CI 1.35–4.53) and hiatal area on maximum Valsalva (OR 1.89, 95% CI 1.27–2.80). Conclusion During counselling for pessary treatment a higher risk of failure due to the aforementioned parameters should be discussed and modifiable parameters should be addressed. More research is needed on the association between anatomical parameters and specific reasons for unsuccessful pessary fitting.