Anatomy and histology of apical support: a literature review concerning cardinal and uterosacral ligaments

Basic vs electromyographic biofeedback-assisted pelvic floor muscle training for the improvement of sexual function after total hysterectomy: a prospective study

Background

Pelvic floor muscle training (PFMT) has emerged as a potential intervention to improve post-total hysterectomy (TH) sexual function. Electromyographic (EMG) biofeedback is an adjunct that may improve outcomes.

Aim

In this study we aimed to compare the EMG biofeedback-assisted PFMT and PFMT alone for improving sexual function in women after TH.

Methods

For this prospective study we enrolled women undergoing TH in our hospital between January 2022 and April 2023. Participants were divided according to the treatment they selected: EMG biofeedback-assisted PFMT or PFMT alone.

Outcomes

The primary study outcome was change in patient sexual function evaluated by use of the Female Sexual Function Index. Secondary outcomes were changes in anxiety and depression evaluated with the Hospital Anxiety and Depression Scale score and pelvic floor muscle strength was evaluated with the Glazer assessment performed from before to after treatment.

Results

A total of 73 patients were included, with 38 patients treated with Electromyographic biofeedback-assisted pelvic floor muscle training. After treatment, sexual function was significantly improved compared to baseline in all patients (all P < .001). Compared to patients with pelvic floor muscle training, the changes in total Female Sexual Function Index scores from before to after treatment in patients with Electromyographic biofeedback-assisted pelvic floor muscle training were significantly higher (all P < .05). There were no significant differences between the 2 groups in the changes in the Glazer score and Hospital Anxiety and Depression Scale scores from before to after treatment (both P > .05).

Clinical Translation

The results demonstrate that Electromyographic biofeedback-assisted pelvic floor muscle training may be used to improve the sexual function of patients following TH.

Strengths and Limitations

This study is limited by its single-center design, small sample size, lack of randomization, and absence of estrogen monitoring in enrolled participants.

Conclusions

Electromyographic biofeedback-assisted pelvic floor muscle training appears to be more effective than pelvic floor muscle training alone in improving sexual function among patients after total hysterectomy.

MRI characterization of pelvic floor ligaments in nulliparous women: Technique development and morphometry within the 3D pelvic inclination correction system (3D-PICS)

PURPOSE

The aim of the MRI-study was to evaluate the visibility of the pelvic floor ligaments and to analyze the ligament morphometry in 3D space.

METHODS

Twenty-two nulliparous women underwent MRI with a ligament specific protocol. MR datasets were evaluated using the 3D Pelvic Inclination Correction System (3D-PICS). The round ligament (RL), sacrospinous ligament (SSL), sacrotuberous ligament (STL), urogenital diaphragm (UGD) and uterosacral ligament (USL) were analyzed. Qualitative and quantitative analysis was performed. 3D coordinates for origin and insertion points were determined relative to the symphysis; subsequently lengths and angles were calculated. Interrater reliability was calculated to validate the point determination method.

RESULTS

Moderate to good visibility was reported for the RL, the SSL, the STL and the UGD. Standard deviation of the points analyzed in the different dimensions vary from 1.5 mm to 21.3 mm. Origin and insertion points of the ligaments are found within a mean standard distance of 10.7 mm. The highest variability was seen in insertion points of RL, with a standard distance of 25.4 mm. The interrater reliability was good to very good (range of intraclass correlation coefficients (ICC) from 0.58 to 0.96), except for the UGD ventral points (ICC from 0.27 to 0.55).

CONCLUSIONS

This in-vivo MRI technique development study offers first exact data describing the pelvic floor ligaments in nulliparous women in 3D-PICS. Visibility, exact 3D coordinates of the origin and insertion points, lengths, angles and interrater reliability assessed for all parameters were evaluated morphometrically.

Single-cell analysis of uterosacral ligament revealed cellular heterogeneity in women with pelvic organ prolapse

Pelvic organ prolapse (POP) markedly affects the quality of life of women, including significant financial burden. Using single-cell RNA sequencing, we constructed a transcriptional profile of 30,452 single cells of the uterosacral ligament in POP and control samples, which has never been constructed before. We identified 10 major cell types, including smooth muscle cells, endothelial cells, fibroblasts, neutrophils, macrophages, monocytes, mast cells, T cells, B cells, and dendritic cells. We performed subpopulation analysis and pseudo-time analysis of POP primary cells, and explored differentially expressed genes. We verified previous cell clusters of human neutrophils of uterosacral ligaments. We found a significant reduction in receptor-ligand pairs related to ECM and cell adhesion between fibroblasts and endothelial cells in POP. The transcription factors related to the extracellular matrix, development, and immunity were identified in USL. Here we provide insight into the molecular mechanisms of POP and valuable information for future research directions.

Prospective diagnostic test accuracy of transvaginal ultrasound posterior approach for uterosacral ligament and torus uterinus deep endometriosis

OBJECTIVE

To determine the diagnostic test accuracy of transvaginal ultrasound (TVS) using a standardized technique for the diagnosis of deep endometriosis (DE) of the uterosacral ligaments (USLs) and adjacent torus uterinus (TU).

METHODS

This was a prospective diagnostic test accuracy study conducted at the McMaster University Medical Center Tertiary Endometriosis Clinic, Hamilton, ON, Canada. Consecutive participants were enrolled if they successfully underwent TVS and surgery by our team from 10 August 2020 to 31 October 2021. The index test was TVS using a standardized posterior approach performed and interpreted by an expert sonologist. The reference standard included direct surgical visualization on laparoscopy by the same person who performed and interpreted the ultrasound scans. Accuracy, sensitivity, specificity, positive and negative predictive values (PPV and NPV) and positive and negative likelihood ratios were calculated for the TVS posterior approach for each location using the reference standard.

RESULTS

There were 54 consecutive participants included upon completion of laparoscopy and histological assessment. The prevalence of DE for the left USL, right USL and TU was 42.6%, 22.2% and 14.8%, respectively. Based on surgical visualization as the reference standard, TVS demonstrated an accuracy of 92.6% (95% CI, 82.1-97.9%), sensitivity of 82.6% (95% CI, 61.2-95.1%), specificity of 100% (95% CI, 88.8-100%), PPV of 100% and NPV of 88.6% (95% CI, 76.1-95.0%) for diagnosing DE in the left USL. For DE of the right USL, TVS demonstrated an accuracy of 94.4% (95% CI, 84.6-98.8%), sensitivity of 75.0% (95% CI, 42.8-94.5%), specificity of 100% (95% CI, 91.6-100%), PPV of 100% and NPV of 93.3% (95% CI, 84.0-97.4%). For DE of the TU, TVS demonstrated an accuracy of 100% (95% CI, 93.4-100%), sensitivity of 100% (95% CI, 63.1-100%), specificity of 100% (95% CI, 92.3-100%), PPV of 100% and NPV of 100%.

CONCLUSIONS

We observed high diagnostic test accuracy of the evaluated standardized TVS technique for assessing DE of the USLs and TU. Further studies evaluating this technique should be performed, particularly with less experienced observers, before considering this technique as the standard approach. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Association between voiding lower urinary tract symptoms and findings on dynamic magnetic resonance imaging with regard to pelvic organs and their supportive structures

OBJECTIVES

Pelvic organ prolapse (POP) causes voiding lower urinary tract symptoms (vLUTS). In the present study, we investigated the association between vLUTS and pelvic organ mobility (POM), including relevant supportive structures, on dynamic magnetic resonance imaging (dMRI).

METHODS

We included 118 patients who had POP of stage II or less before straining and stage III or more when straining during dMRI. The presence of vLUTS and overactive bladder (OAB) was determined by a voiding subscore of the International Prostate Symptom Score (vIPSS) ≥5 and the OAB symptom score, respectively. POM was measured by dMRI before and during straining, and patients with and without vLUTS as well as patients with and without vLUTS and/or OAB were compared. p < .05 was considered to be statistically significant.

RESULTS

According to vIPSS, 42 patients (35.6%) had vLUTS. On dMRI, patients with vLUTS showed a significantly more ventral position and/or movement of the bladder and cervix. Moreover, patients with vLUTS and OAB had significantly more ventral movement of the uterine cervix and a larger strain on imaginary uterosacral and cardinal ligaments than those without these symptoms. In addition, patients with vLUTS and OAB had significantly higher vIPSS than those with vLUTS alone.

CONCLUSIONS

vLUTS may be associated with the proximity of the bladder and cervix to the pubic bone and consequent compression of the urethra by the prolapsed organs. vLUTS with OAB might indicate more advanced lower urinary tract dysfunction than vLUTS alone.

Radical Hysterectomy or Total Mesometrial Resection-Two Anatomical Concepts for Surgical Treatment of Cancer of the Uterine Cervix

A radical hysterectomy is the standard method of surgical treatment for patients with early-stage cancer of the uterine cervix. It was first introduced more than 100 years ago. Since then, various and many different radical procedures, which diverge in terms of radicality, have been described. Inconsistencies are clearly seen in practical anatomy, which were defined as surgically created artifacts. Moreover, the disparity of the procedure is most notable regarding the terminology of pelvic connective tissues and spaces. Despite these controversies, the procedure is widely performed and implemented in the majority of guidelines for the surgical treatment of cancer of the uterine cervix. However, a different and unique concept of surgical treatment of cervical cancer has been reported. It is based on ontogenetic anatomy and maps any tissue in the mature organism according to its embryologic development. The clinical implementation of this theory in the context of early cervical cancer is total mesometrial resection. The present article aims to describe and compare the anatomical and surgical basics of a radical hysterectomy (type C1/C2) and total mesometrial resection. Discrepancies regarding the terminology, resection lines, and surgical planes of both procedures are highlighted in detail. The surgical anatomy of the pelvic autonomic nerves and its surgical dissection is also delineated. This is the first article that compares the discrepancy of classic anatomy and ontogenic anatomy regarding surgical treatment of cancer of the uterine cervix. Clinical data, oncological outcome, and neoadjuvant and adjuvant treatment regarding both procedures are not the topic of the present article.

Comparison of in vivo visco-hyperelastic properties of uterine suspensory tissue in women with and without pelvic organ prolapse

The uterine suspensory tissue (UST) complex includes the cardinal (CL) and uterosacral "ligaments" (USL), which are mesentery-like structures that play a role in resisting pelvic organ prolapse (POP). Since there is no information on the time-dependent material properties of the whole structure in situ and in vivo, we developed and tested an intraoperative technique to quantify in vivo whether there is a significant difference in visco-hyperelastic behavior of the CL and USL between women with and without POP. Thirteen women with POP (cases) and four controls scheduled for surgery were selected from an ongoing POP study. Immediately prior to surgery, a computer-controlled linear servo-actuator with a series force transducer applied a continuous, caudally directed traction force while simultaneously recording the resulting cervical displacement in the same direction. After applying an initial 1.1 N preload, a ramp rate of 4 mm/s was used to apply a maximum force of 17.8 N in three "ramp-and-hold" test trials. A simplified bilateral four-cable biomechanical model was used to identify the material behavior of each ligament. For this, the initial cross-section areas of the CL and USL were measured on 3-T magnetic resonance image-based 3D models from each subject. The time-dependent strain energy function of CL/USL was defined with a three-parameter hyperelastic Mooney-Rivlin material model and a two-term Prony series in relaxation form. When cases were compared with controls, the estimated time-dependent material constants of CL and USL did not differ significantly. These are the first measurements that compare the in vivo and in situ visco-hyperelastic response of the tissues comprising the CL and USL to loading in women with and without prolapse. Larger sample sizes would help improve the precision of intergroup differences.

In-plane and out-of-plane deformations of gilt utero-sacral ligaments

The uterosacral ligaments (USLs) are supportive structures of the uterus and apical vagina. The mechanical function of these ligaments within the pelvic floor is crucial not only in normal physiological conditions but also in reconstructive surgeries for pelvic organ prolapse. Discrepancies in their anatomical and histological description exist in the literature, but such discrepancies are likely due to large variations of these structures. This makes mechanical testing very challenging, requiring the development of advanced methods for characterizing their mechanical properties. This study proposes the use of planar biaxial testing, digital image correlation (DIC), and optical coherence tomography (OCT) to quantify the deformations of the USLs, both in-plane and out-of-plane. Using the gilts as an animal model, the USLs were found to deform significantly less in their main direction (MD) of in vivo loading than in the direction perpendicular to it (PD) at increasing equibiaxial stresses. Under constant equibiaxial loading, the USLs deform over time equally, at comparable rates in both the MD and PD. The thickness of the USLs decreases as the equibiaxial loading increases but, under constant equibiaxial loading, the thickness increases in some specimens and decreases in others. These findings could contribute to the design of new mesh materials that augment the support function of USLs as well as noninvasive diagnostic tools for evaluating the integrity of the USLs.

Is the Deep Endometriosis or the Surgery the Cause of Postoperative Bladder Dysfunction?

STUDY OBJECTIVE

To assess if deep endometriosis surgery affects the bladder function.

DESIGN

Prospective multicenter observational study (Canadian Task Force classification II-2).

SETTING

Academic researches centers.

PATIENTS

Thirty-two patients with diagnosis of deep endometriosis requiring surgery.

INTERVENTIONS

Women were evaluated with urodynamic studies, ICIQ-UI SF and ICIQ-OAB questionnaires before and 3 months after surgery.

MEASUREMENTS AND MAIN RESULTS

The main outcome measure was the impact of deep endometriosis surgery on urodynamic parameters. All cystomanometric parameters showed an improvement postoperatively: in particular, the first desire to void (120 vs 204 ml, p<0.001) and the bladder capacity (358 vs 409 ml, p=0.011) increased significantly after surgery. Of the uroflow parameters, the maximal voiding flow improved significantly postoperatively (19 vs 25 ml/sec, p=0.026). The ICIQ-UI SF (2.5 vs 0, p=0.0005) and ICIQ-OAB (4.3 vs 1.2, p<0.001) questionnaires showed a significant postoperative improvement too.

CONCLUSIONS

Our data show that in a selected population of patients with DE (not requiring bowel or urethral resection), the bladder function improves after surgery, both during filling and on voiding urodynamic phases. Postoperatively, patients with DE become aware of bladder filling later, have a higher bladder capacity and have a higher maximal flow. The postoperative urodynamic results are corroborated by the improved scores on the bladder questionnaires.

Mechanics of Uterosacral Ligaments: Current Knowledge, Existing Gaps, and Future Directions

The uterosacral ligaments (USLs) are important anatomical structures that support the uterus and apical vagina within the pelvis. As these structures are over-stretched, become weak, and exhibit laxity, pelvic floor disorders such as pelvic organ prolapse occur. Although several surgical procedures to treat pelvic floor disorders are directed toward the USLs, there is still a lot that is unknown about their function. This manuscript presents a review of the current knowledge on the mechanical properties of the USLs. The anatomy, microstructure, and clinical significance of the USLs are first reviewed. Then, the results of published experimental studies on the in vivo and ex vivo, uniaxial and biaxial tensile tests are compiled. Based on the existing findings, research gaps are identified and future research directions are discussed. The purpose of this exhaustive review is to help new researchers navigate scientific literature on the mechanical properties of the USLs. The use of these structures remains very popular in reconstructive surgeries that restore and augment the support of pelvic organs, especially as synthetic surgical mesh implants continue to be highly controversial.

A New Anatomic and Staging-Oriented Classification of Radical Hysterectomy

Simple Summary

The main deficits of the available classifications of radical hysterectomy are the facts that they are based only on the lateral extension of resection, do not depend on the precise anatomy of parametrium and paracolpium and do not correlate with the tumour stage, size or infiltration in the vagina. This new suggested classification depends on the 3-dimentional concept of parametrium and paracolpium and the comprehensive description of the anatomy of parametrium, paracolpium and the pelvic autonomic nerve system. Each type in this classification tailored to the tumour stage according to FIGO- classification from 2018, taking into account the tumour size, localization and infiltration in the vaginal vault, which may make it the most suitable tool for planning and tailoring the surgery of radical hysterectomy.

Abstract

The current understanding of radical hysterectomy more is centered on the uterus and little is being discussed about the resection of the vaginal cuff and the paracolpium as an essential part of this procedure. This is because that the current classifications of radical hysterectomy are based only on the lateral extent of resection. This way is easier to be understood but does not reflect the anatomical and surgical conception of radical hysterectomy and the three-dimensional ways of tumour spreading, neither meet the need of adjusting the radicality according to the different stages of FIGO classification, which depends—at least in the early stages—on the tumour volume and the infiltration in the vagina (but not on the directly spread in the parametrium). The new classification presented in this paper does not base anymore on the lateral extent of resection only but too on the depth of resection in the small pelvic and the extent of the resected vaginal vault without or with its three-dimensional paracolpium. This classification takes into account the tumour size, stage, localization and infiltration in the vaginal vault and may offer the optimal tool to adjust and tailor the surgery according to these important variables.

Association between overactive bladder and pelvic organ mobility as evaluated by dynamic magnetic resonance imaging

Overactive bladder (OAB) is a prevalent condition, which negatively impacts patients’ quality of life. Pelvic organ prolapse (POP), also prevalent in women, has been recognized as an important etiology of female OAB, although the pathophysiological mechanisms remain controversial. In this study, we reviewed findings of dynamic magnetic resonance imaging (dMRI) in 118 patients with POP and investigated the association between dMRI findings, including positions and mobilities of pelvic organs as well as parameters of pelvic organ support and bladder outlet obstruction (urethral kinking), and OAB in order to elucidate the pathophysiology of OAB in patients with POP. Our results showed that compared with non-OAB patients, OAB patients had a significantly higher body mass index, more severe pelvic floor muscle impairment, and more profound supportive defects in the uterine cervix (apical compartment). On the other hand, dMRI parameters showed hardly any significant difference between patients with mild and moderate to severe OAB. These findings may imply that levator ani impairment and defective supports of the apical compartment could be associated with the presence of OAB and that the severity of OAB could be affected by factors other than those related to pelvic organ mobility and support or urethral kinking.

Pelvic Floor Dysfunction After Hysterectomy: Moving the Investigation Forward

The role of hysterectomy in the development of pelvic floor dysfunction (PFD) remains widely disputed. The controversy is fueled by two key factors. The first is conflicting association studies that make it difficult to establish whether a link truly exists. Although many retrospective studies report a correlation between hysterectomy and increased risk of stress urinary incontinence (SUI) or pelvic organ prolapse (POP), prospective studies often fail to replicate these results, leading some to conclude that no association exists. However, most prospective studies do not follow up for a sufficient length of time to account for the long latency of PFD and cannot unilaterally prove the absence of an association. The second source of controversy is the absence of a plausible mechanism to explain how hysterectomy could predispose patients to PFD. In this paper, we investigate autonomic innervation and smooth muscle in the three layers of pelvic floor support and propose a mechanism through which autonomic damage from hysterectomy could predispose patients to PFD. We then identify key research areas needed to evaluate this theory. This report aims to inspire a discussion on how to further the collective understanding of the relationship between hysterectomy and PFD. Clarifying the nature of this connection could have enormous consequences in redefining the risks and benefits of hysterectomy.

Paracervical Block or Uterosacral Ligament Infiltration for Benign Minimally Invasive Hysterectomy: A Systematic Review and Meta-analysis

Objective

The aim of this study was to estimate the efficacy of preemptive paracervical block or uterosacral ligament infiltration in reducing postoperative pain and opioid consumption after benign minimally invasive hysterectomy.

Data Sources

We searched MEDLINE, Cochrane Library, Embase, ClinicalTrials.gov, and Google Scholar from inception until February 2020.

Methods of Study Selection

We identified randomized placebo-controlled trials assessing the primary outcome of pain and opioid consumption after paracervical block or uterosacral infiltration in benign laparoscopic, vaginal, or robotic hysterectomy. Two investigators evaluated studies for risk of bias and quality of evidence.

Tabulation, Integration, and Results

We reviewed 219 abstracts; 6 studies met the inclusion criteria: 3 using paracervical block (2 vaginal and 1 laparoscopic) and 3 using uterosacral ligament infiltration (all vaginal). Two studies were included in the meta-analysis (both vaginal hysterectomy). Because of lack of numerical data, or comparison, the other 4 studies are reported in narrative form. Three controlled trials reported a moderate benefit from paracervical block up to 8 hours after vaginal and 4 hours after laparoscopic surgery. Meta-analysis could not be performed because of the lack of numerical data for pooling results or the lack of a laparoscopic hysterectomy comparison group. Three trials reported that uterosacral infiltration decreases pain up to 6 hours after vaginal hysterectomy, and meta-analysis pooling the results of 2 of these studies demonstrated improvement in pain up to 4 hours on a 0- to 100-mm visual analog scale for pain (-19.97 mm; 95% confidence interval, -29.02 to -10.91; P < 0.000). Five trials reported a moderate reduction in cumulative opioid use within 24 hours after vaginal surgery for both paracervical block and uterosacral infiltration. Meta-analysis was not performed for paracervical block because only 1 trial provided suitable data for pooling. Meta-analysis pooling the results of 2 trials of uterosacral infiltration demonstrated opioid consumption of 20.73 morphine milligram equivalents less compared with controls (95% confidence interval, -23.54 to -17.91; P < 0.000).

Conclusions

There were a total of 6 randomized placebo-controlled studies evaluated in this study. Although a meta-analysis was unable to be performed for all studies because of lack of comparison groups or numerical data, there is evidence that preemptive uterosacral ligament infiltration may reduce postoperative pain and opioid consumption after vaginal hysterectomy. Our study does not allow us to make any substantive conclusions on the use of paracervical block in vaginal hysterectomy or the use of either type of injection in laparoscopic or robotic hysterectomy.

The distribution of pelvic organ support defects in women undergoing pelvic organ prolapse surgery and compartment specific risk factors

Introduction and hypothesis

The objective of our study was to describe the distribution of pelvic organ prolapse (POP) in a population of women undergoing POP reconstructive surgery and to identify compartment-specific risk factors.

Methods

We conducted a retrospective observational study in a cohort of 326 women who underwent POP repair and had a standardized preoperative POP assessment using the Baden-Walker classification. The distribution of POP grade was described for each vaginal compartment. The association between the involvement of each specific compartment and predictors was evaluated with a logistic regression model.

Results

The frequency of significant POP (grade ≥ 2) was 79% in the anterior compartment, 49% in the middle/apical compartment and 31% in the posterior compartment. Combined significant anterior and apical defects were present in 25% of women. Increasing age was a significant risk factor for apical defect (between 60 and 70 years OR = 2.4, 95% CI 1.2–4.6; > 70 years OR = 3.4, 95% CI 1.7–6.6). Previous hysterectomy (OR = 2.2, 95% CI 1.0–4.6) was a significant risk factor for posterior defect.

Conclusions

In a population undergoing POP surgery, anterior compartment involvement is the most common and serious defect and can often be associated with an apical defect, especially in older women. In case of previous hysterectomy, the posterior compartment may be weakened. These findings may help surgeons to select the appropriate POP reconstructive surgery, which often should address both anterior and apical defects.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00192-021-04826-7.

Transvaginal ultrasound features of normal uterosacral ligaments

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.

Evaluation of Different 'Tensioning' of Apical Suspension in Women Undergoing Surgery for Prolapse and Urinary Incontinence

BACKGROUND

According to the literature, restoration of pelvic organ prolapse also restores urinary continence. However, it is difficult to determine which exact surgical procedure actually led to urinary continence due to a lack of standardisation among these techniques. For example, an apical fixation is broadly defined in terms of type and shape of implanted material, anatomical fixation sides and tensioning. The aim of this study was to evaluate the effect of bilateral uterosacral ligament replacement with alloplastic tapes of defined lengths on symptoms of urinary incontinence.

PATIENTS AND METHODS

Patients with urinary incontinence and pelvic organ prolapse underwent an apical suspension. Thereby, both uterosacral ligaments (USL) were replaced by alloplastic structures of defined length. These alloplastic tapes had defined lengths in all patients of 9, 10, or 11 cm in length. They were sutured on both sides of the cervix, placed in the left and right peritoneal fold of the USL, and were sutured laterally to the prevertebral fascial layer of the sacral vertebra at the level of S2. Furthermore, all patients received additional transobturator tape. Pelvic organ prolapse was classified according to the Baden-Walker system, and urinary incontinence symptoms according to validated questionnaires.

RESULTS

Four months after bilateral USL replacement, apical suspension was restored in all 31 patients. In addition, urinary continence was re-established in 18 out of these 31 patients (58%). The highest continence rate was observed in patients in which both USL were replaced with alloplastic tapes of 9 cm in length.

CONCLUSION

The findings indicated the importance of USL integrity for urinary continence. In particular, a defined length for both USL seems to be important for (re-)establishing urinary continence.

Using the novel pelvic organ prolapse histologic quantification system to identify phenotypes in uterosacral ligaments in women with pelvic organ prolapse

BACKGROUND

Pelvic organ prolapse is common, but the underlying etiologies are poorly understood, which limits our current prevention and treatment options.

OBJECTIVE

Our primary objective was to compare the uterosacral ligament histologic features in women with and without prolapse using the novel pelvic organ prolapse histologic quantification system. Our secondary aim was to determine whether composite histologic findings in uterosacral ligaments are associated with prolapse risk factors.

STUDY DESIGN

This was a prospective cohort study in which paracervical uterosacral ligament biopsies were performed at the time of hysterectomy for primary prolapse or other benign gynecologic indications and processed for histologic evaluation. The pelvic organ prolapse quantification system was used to determine the prolapse stage. In this study, 9 prominent histologic features were semiquantitatively scored using the pelvic organ prolapse histologic quantification system in a blinded fashion and compared between prolapse and control groups. Unbiased principal component analysis of these scores was independently performed to identify potential relationships between histologic measures and prolapse risk factors.

RESULTS

The histologic scores of 81 prolapse and 33 control ligaments were analyzed. Compared with the control group, women in the prolapse group were significantly older and more likely to be in the menopausal phase. There was no difference in the number of vaginal deliveries, body mass index, hormone use, or smoking status between the groups. To control for baseline differences, patients were also stratified by age over 40 years and menopausal status. Compared with the control group, the prolapse ligaments in the premenopausal group had significantly more loss of smooth muscle fibers within the fascicles (P<.001), increased inflammatory infiltrates of neutrophils within the tissue and perineural inflammatory cells (P<.01 and P=.04, respectively), and reduced neointimal hyperplasia (P=.02). Prolapse ligaments in the postmenopausal group exhibited elevated adipose content compared with that of the control group (P=.05). Amount of fibrillar collagen, total nonvascular smooth muscle, and muscle fiber vesicles of prolapse ligaments did not differ in either the premenopausal or postmenopausal group compared with that of the control group. Unbiased principal component analysis of the histologic scores separated the prolapse ligaments into 3 phenotypes: (1) increased adipose accumulation, (2) increased inflammation, and (3) abnormal vasculature, with variable overlap with controls. Posthoc analysis of these subgroups demonstrated a positive correlation between increasing number of vaginal deliveries and body mass index with increasing adipose content in the adipocyte accumulation and inflammatory phenotype and increasing neointimal hyperplasia in the vascular phenotype. However, only the relationship between vaginal delivery and adipocytes was significant in the adipose phenotype (R²=0.13; P=.04).

CONCLUSION

Histologic phenotypes exist in pelvic support ligaments that can be distinguished using the pelvic organ prolapse histologic quantification system and principle component analysis. Vaginal delivery is associated with aberrant adipose accumulation in uterosacral ligaments. Our findings support a multifactorial etiology for pelvic organ prolapse contributing to altered smooth muscle, vasculature, and connective tissue content in crucial pelvic support structures. To confirm these associations and evaluate the biomechanical properties of histologic phenotypes of prolapse, larger studies are warranted. Closing this gap in knowledge will help optimize personalized medicine and help identify targets for prevention and treatment of this complex condition.

Twenty-first century radical hysterectomy - Journey from descriptive to practical anatomy

The resulting characteristics of 20th century radical hysterectomy demonstrated that, in the quest for a radical cure, its surgical procedure became extended. The consequences of this were increased difficulty in the procedure with risk of massive hemorrhage and vesical and anorectal dysfunction. Moreover, the cardinal and transverse cervical ligaments, which were individually recognized during the 19th century, became regarded as synonymous during the middle of the 20th century. Because of this, traditional surgical procedures such as Wertheim and Latzko's were not precisely followed, further delaying the advent of a new idea(s) for radical hysterectomy. The desired goal for 21st radical hysterectomy should be an anatomy and operative procedure that clarify and rectify these aforementioned negative surgical outcomes. In 1998, International Federation of Associations of Anatomists (IFAA) introduced clinical terminology in Terminologia Anatomica. With the IFAA's decision in mind, the author focused, out of the many theories and surgical procedures for cancer of the uterine cervix, on three noteworthy proposals. From these proposals, the possibility for a new idea(s) on theories and surgical procedures was explored through the fusion of anatomy and clinical practice. The idea for a new procedure(s) required a morphological distinction between description in textbooks and intraoperative findings, that is: a) a traditional anatomy that was based on gross/systemic anatomy; and b) an anatomy in which part of an artifact resulting from applying an artificial maneuver to a living body could be regarded as surgical anatomy. The author has tentatively called the former descriptive anatomy and the latter practical anatomy. The development of this practical anatomy led to the idea for and practical application of a less-extirpating and nerve-sparing operation, which improved patient's outcome. Radical hysterectomy of the 21st century should be conducted following this new anatomy that is concentrated around practical anatomy and independent from descriptive anatomy.

A Concise Paradigm on Radical Hysterectomy: The Comprehensive Anatomy of Parametrium, Paracolpium and the Pelvic Autonomic Nerve System and Its Surgical Implication

The current understanding of radical hysterectomy is more centered on the uterus and little is discussed regarding the resection of the vaginal cuff and the paracolpium as an essential part of this procedure. The anatomic dissections of two fresh and 17 formalin-fixed female pelvis cadavers were utilized to understand and decipher the anatomy of the pelvic autonomic nerve system (PANS) and its connections to the surrounding anatomical structures, especially the paracolpium. The study mandates the recognition of the three-dimensional (3D) anatomic template of the parametrium and paracolpium and provides herewith an enhanced scope during a nerve-sparing radical hysterectomy procedure by precise description of the paracolpium and its close anatomical relationships to the components of the PANS. This enables the medical fraternity to distinguish between direct infiltration of the paracolpium, where the nerve sparing technique is no longer possible, and the affected lymph node in the paracolpium, where nerve sparing is still an option. This study gives rise to a tailored surgical option that allows for abandoning the resection of the paracolpium by FIGO stage IB1, where less than 2 cm vaginal vault resection is demanded.

A simplified fascial model of pelvic anatomical surgery: going beyond parametrium-centered surgical anatomy

The classical surgical anatomy of the female pelvis is limited by its gynecological oncological focus on the parametrium and burdened by its modeling based on personal techniques of different surgeons. However, surgical treatment of pelvic diseases, spreading beyond the anatomical area of origin, requires extra-regional procedures and a thorough pelvic anatomical knowledge. This study evaluated the feasibility of a comprehensive and simplified model of pelvic retroperitoneal compartmentalization, based on anatomical rather than surgical anatomical structures. Such a model aims at providing an easier, holistic approach useful for clinical, surgical and educational purposes. Six fresh-frozen female pelves were macroscopically and systematically dissected. Three superficial structures, i.e., the obliterated umbilical artery, the ureter and the sacrouterine ligament, were identified as the landmarks of 3 deeper fascial-ligamentous structures, i.e., the umbilicovesical fascia, the urogenital-hypogastric fascia and the sacropubic ligament. The retroperitoneal areolar tissue was then gently teased away, exposing the compartments delimited by these deep fascial structures. Four compartments were identified as a result of the intrapelvic development of the umbilicovesical fascia along the obliterated umbilical artery, the urogenital-hypogastric fascia along the mesoureter and the sacropubic ligaments. The retroperitoneal compartments were named: parietal, laterally to the umbilicovesical fascia; vascular, between the two fasciae; neural, medially to the urogenital-hypogastric fascia and visceral between the sacropubic ligaments. The study provides the scientific rational for a model of pelvic retroperitoneal anatomy based on identifiable anatomical structures and suitable for surgical planning and training.

From molecular to macro: the key role of the apical ligaments in uterovaginal support

To explain the pathophysiology of pelvic organ prolapse, we must first understand the complexities of the normal support structures of the uterus and vagina. In this review, we focus on the apical ligaments, which include the cardinal and uterosacral ligaments. The aims of this review are the following: (1) to provide an overview of the anatomy and histology of the ligaments; (2) to summarize the imaging and biomechanical studies of the ligament properties and the way they relate to anterior and posterior vaginal wall prolapse; and (3) to synthesize these findings into a conceptual model for the progression of prolapse.

Comparison of Biaxial Biomechanical Properties of Post-menopausal Human Prolapsed and Non-prolapsed Uterosacral Ligament

Uterosacral ligaments (USLs) provide structural support to the female pelvic floor, and a loss of USL structural integrity or biomechanical function may induce pelvic organ prolapse (POP). Alterations in extracellular matrix composition and organization dictate USL mechanical function. Changes in USL microstructure and corresponding mechanical properties, however, are not fully understood, nor is it understood how microstructure and mechanics change with onset and progression of POP. This is due, in part, as USL properties are primarily characterized along a single direction (uniaxial test), whereas the USL is loaded in multiple directions simultaneously within the body. Biaxial testing permits the acquisition of biomechanical data from two axes simultaneously, and thus simulates a more physiologic assessment compared to the traditional uniaxial testing. Therefore, the objective of this study was to quantify the biaxial biomechanical properties and histological composition of the USL in post-menopausal women with and without POP at various stages. Potential correlations between tissue microstructural composition and mechanical function were also examined. Tangential modulus was lower and peak stretch higher in POP III/IV compared to non-POP and POP I/II in the main in vivo loading direction; however, no significant differences in mechanical properties were observed in the perpendicular loading direction. Collagen content positively correlated to tangential modulus in the main in vivo loading direction (r = 0.5, p = 0.02) and negatively correlated with the peak stretch in both the main in vivo (r = -0.5, p = 0.02) and perpendicular loading directions (r = -0.3, p = 0.05). However, no statistically significant differences in USL composition were observed, which may be due to the small sample size and high variability of small sections of human tissues. These results provide first step towards understanding what microstructural and mechanical changes may occur in the USL with POP onset and progression. Such information may provide important future insights into the development of new surgical reconstruction techniques and graft materials for POP treatment.

Standardized terminology of apical structures in the female pelvis based on a structured medical literature review

The objectives of this study were to review the published literature and selected textbooks, to compare existing usage to that in Terminologia Anatomica, and to compile standardized anatomic nomenclature for the apical structures of the female pelvis. MEDLINE was searched from inception until May 30, 2017, based on 33 search terms generated by group consensus. Resulting abstracts were screened by 11 reviewers to identify pertinent studies reporting on apical female pelvic anatomy. Following additional focused screening for rarer terms and selective representative random sampling of the literature for common terms, accepted full-text manuscripts and relevant textbook chapters were extracted for anatomic terms related to apical structures. From an initial total of 55,448 abstracts, 193 eligible studies were identified for extraction, to which 14 chapters from 9 textbooks were added. In all, 293 separate structural terms were identified, of which 184 had Terminologia Anatomica-accepted terms. Inclusion of several widely used regional terms (vaginal apex, adnexa, cervico-vaginal junction, uretero-vesical junction, and apical segment), structural terms (vesicouterine ligament, paracolpium, mesoteres, mesoureter, ovarian venous plexus, and artery to the round ligament) and spaces (vesicocervical, vesicovaginal, presacral, and pararectal) not included in Terminologia Anatomica is proposed. Furthermore, 2 controversial terms (lower uterine segment and supravaginal septum) were identified that require additional research to support or refute continued use in medical communication. This study confirms and identifies inconsistencies and gaps in the nomenclature of apical structures of the female pelvis. Standardized terminology should be used when describing apical female pelvic structures to facilitate communication and to promote consistency among multiple academic, clinical, and surgical disciplines.

Suspensory Ligaments of the Female Genital Organs: MRI Evaluation with Intraoperative Correlation

The uterus, which plays an important role in the reproductive process, provides a home for the developing fetus and so must be in a stable, though flexible, location. Various structures with suspensory ligaments help provide this berth. MRI with high spatial resolution allows us to detect and evaluate these relatively fine structures. Under physiologic conditions, MRI can be used to depict uterine and ovarian ligaments (ie, the uterosacral, cardinal, and round ligaments, as well as the suspensory ligament of the ovary). In the presence of pathologic conditions (inflammation, endometriosis, tumors), the suspensory ligaments may appear thickened or invaded, which makes their delineation easier. Understanding the normal anatomy of the suspensory ligaments of the female genital organs and using a standardized nomenclature are essential for identifying and reporting related pathologic conditions. The female pelvic anatomy and the suspensory ligaments of the female genital organs are described as depicted with MRI. Also, the compartmental anatomy of the female pelvis is explained, including the extraperitoneal pelvic spaces. Finally, a checklist is provided for structured reporting of the MRI findings in the female pelvis. Online supplemental material is available for this article. ^©RSNA, 2018.

Translabial US and Dynamic MR Imaging of the Pelvic Floor: Normal Anatomy and Dysfunction

Pelvic floor dysfunction (PFD) is a common condition that typically affects women older than 50 years and decreases the quality of life. Weakening of support structures can involve all three pelvic compartments and cause a combination of symptoms, including constipation, urinary and fecal incontinence, obstructed defecation, pelvic pain, perineal bulging, and sexual dysfunction. The causes of PFD are complex and multifactorial; however, vaginal delivery is considered a major predisposing factor. Physical examination alone is limited in the evaluation of PFD; it frequently leads to an underestimation of the involved compartments. Imaging has an important role in the clinical evaluation, yielding invaluable information for patient counseling and surgical planning. Three- and four-dimensional translabial ultrasonography (US) is a relatively new imaging modality with high accuracy in the evaluation of PFD such as urinary incontinence, pelvic organ prolapse, and puborectalis avulsion. Evaluation of mesh implants is another important indication for this modality. Dynamic magnetic resonance (MR) imaging of the pelvic floor is a well-established modality for pelvic floor evaluation, with high-resolution images yielding detailed anatomic information and dynamic sequences yielding functional data. Specific protocols and dedicated image interpretation are required with both of these imaging methods. In this article, the authors review the normal anatomy of the female pelvic floor by using a practical approach, discuss the roles of translabial US and MR imaging in the investigation of PFD, describe the most appropriate imaging protocols, and illustrate the most common imaging findings of PFD in the anterior, middle, and posterior compartments of the pelvis. Online supplemental material is available for this article. ^©RSNA, 2018.

Mechanical Analysis of the Uterosacral Ligament: Swine vs. Human

The uterosacral ligament (USL) is a major suspensory structure of the female pelvic floor, providing support to the cervix and/or upper vagina. It plays a pivotal role in surgical procedures for pelvic organ prolapse (POP) aimed at restoring apical support. Despite its important mechanical function, little is known about the mechanical properties of the USL due to the constraints associated with in vivo testing of human USL and the lack of validated large animal models that enable such investigations. In this study, we provide the first comparison of the mechanical properties of swine and human USLs. Preconditioning and pre-creep data up to a 2 N load and creep data under a 2 N load over 1200 s were obtained on swine (n = 9) and human (n = 9) USL specimens by performing planar equi-biaxial tensile tests and using the digital image correlation method. No differences in the peak strain during preconditioning tests, secant modulus of the pre-creep response, and strain at the end of creep tests were detected in the USLs from the two species along both axial loading directions (the main in vivo loading direction and the direction that is perpendicular to it). These findings suggest that the swine holds promise as large animal model for studying the mechanical role of the USL in apical vaginal support and treatment of POP.

Comprehensive Review of the Cardinal Ligament

The cardinal ligament is thought to be one of the important structures in providing support and stabilization for the pelvic organs e.g., the uterus. However, many discrepancies exist in the literature regarding terminology, anatomy, and histology. The cardinal ligament attaches the lateral side of the vagina and cervix to the lateral pelvic wall, which provides support to the vagina and cervix. Studies have shown variable findings in the collagen content and distribution in the cardinal ligaments of women with a prolapsed uterus. Uterine vessels and the branches of the inferior hypogastric plexus travel in the cardinal ligament, which is of great importance during pelvic surgeries. Cervical cancer may lead to metastatic spread to the lymph nodes juxtaposed to the cardinal ligaments. This review aims to highlight the clinical significance and surgical importance of the cardinal ligament with a comparison with previous studies.

Beta-3 adrenoceptor expression in the uterosacral ligament in the postmenopausal women with pelvic organ prolapse

AIMS

β3-adrenoceptor (β3-AR) agonist is known to relax the detrusor muscles. Considering that both pelvic organ prolapse (POP) and overactive-bladder (OAB) are frequently seen in the elderly population, the effect of β3-AR agonist on the pelvic floor tissues should be investigated. As a first step, this pilot, experimental, and descriptive study was designed to investigate the presence of β3-AR expression in the uterosacral-ligaments (USLs) in postmenopausal (PMP) women with POP.

METHODS

After informed consent, PMP women undergoing hysterectomy for POP were recruited for the intraoperative collection of distal USL between 5/2016 and 8/2016. H&E analysis for the USLs and immunohistochemistry (IHC) analysis for β3-AR and α-actin smooth muscle (SM) were carried out. Tissue composition and percentage of β3-AR expression in the USLs were subjectively measured and the staining results were expressed as descriptive analysis.

RESULTS

Total 11 USL specimens were collected and nine specimens were included for the final analysis (one specimen: used for antibody concentration adjustment and one specimen: failed proper staining). Under high-power-field, the USLs were composed of SM cells (81.5 ± 7.47%) and connective tissues (16.5 ± 7.9%). On IHC analysis, six out of nine specimens expressed β3-AR with a different level of expression in SM cells in the USLs.

CONCLUSIONS

The majority of distal USLs were composed of SM cells. β3-ARs are expressed in 67% of the study specimens. Considering that both POP and OAB are frequently seen in the elderly population, the effect of β3-AR agonist on the pelvic floor tissues should be investigated further.

Laparoscopic high uterosacral ligament suspension: an alternative route for a traditional technique

INTRODUCTION AND HYPOTHESIS

Uterovaginal prolapse treatment is a challenge for the urogynecologist. Surgical management for apical prolapse can be successful with native tissue and uterosacral ligament (USL) fixation. However, some complications have been described, especially with use of the vaginal approach. The aim of this video is to describe an alternative laparoscopic approach to a traditional vaginal procedure to reduce nerve injury and ureteral complications.

METHODS

A 75-year-old woman was referred to our unit for symptomatic stage III apical prolapse and underwent laparoscopic USL fixation, according to the technique described herein.

RESULTS

This surgical technique was successful in correcting apical prolapse.

CONCLUSIONS

This video tutorial may be useful to urogynecologists for improving surgical technique, thus leading to a reduction in the risk of nerve and ureteral complications. The technique offers the possibility of a correct under-vision suture positioning. Laparoscopic USL fixation can be safely performed to treat apical prolapse.

What's new in the functional anatomy of pelvic organ prolapse?

PURPOSE OF REVIEW

Provide an evidence-based review of pelvic floor functional anatomy related to pelvic organ prolapse.

RECENT FINDINGS

Pelvic organ support depends on interactions between the levator ani muscle and pelvic connective tissues. Muscle failure exposes the vaginal wall to a pressure differential producing abnormal tension on the attachments of the pelvic organs to the pelvic sidewall. Birth-induced injury to the pubococcygeal portion of the levator ani muscle is seen in 55% of women with prolapse and 16% of women with normal support. Failure of the lateral connective tissue attachments between the uterus and vagina to the pelvic wall (cardinal, uterosacral, and paravaginal) are strongly related with prolapse (effect sizes ∼2.5) and are also highly correlated with one another (r ∼ 0.85). Small differences exist with prolapse in factors involving the vaginal wall length and width (effect sizes ∼1). The primary difference in ligament properties between women with and without prolapse is found in ligament length. Only minor differences in ligament stiffness are seen.

SUMMARY

Pelvic organ prolapse occurs because of injury to the levator ani muscles and failure of the lateral connections between the pelvic organs to the pelvic sidewall. Abnormalities of the vaginal wall fascial tissues may play a minor role.

Surgical Anatomy of the Uterosacral Ligament Colpopexy

OBJECTIVE

The aim of this study was to describe the relationship of the uterosacral ligament (USL) to the ureter and rectum along a surgeon's target location for suture placement under conditions simulating live surgery.

METHODS

Dissections were performed in 11 unembalmed female cadavers. Steps were taken to identify the USL simulating USL colpopexy. Pins were placed in the midportion of the USL at the level of the IS, and at 1-cm, 2-cm, and 3-cm increments traveling proximally toward the sacrum (Fig. 1). We measured minimum distances from the USL to the ureter and rectum at each target location.

RESULTS

In general, the ureters range from 1.3 to 2.0 cm lateral to the USLs along the target length. The rectum ranges from 1.9 to 2.6 cm from the right USL and remains 1.5 cm from the left USL. The mean change in distance between the ureter and USL for every 1 cm advanced toward the sacrum is 0.2 cm (95% confidence interval [CI], 0.19-0.24) on the right and 0.2 cm (95% CI, 0.18-0.27) on the left. The mean change in distance between the rectum and USL for every 1 cm advanced toward the sacrum is 0.2 cm (95% CI, 0.19-0.24) on the right and 0.0 cm (95% CI, 0-0) on the left.

CONCLUSIONS

For every centimeter traveled along the bilateral USLs from the IS toward the sacrum, the ureter moves 0.2 cm laterally away from the ligament, the rectum moves 0.2 cm medially away from the right USL, but maintains its position from the left USL.

Effects of repeated biaxial loads on the creep properties of cardinal ligaments

The cardinal ligament (CL) is one of the major pelvic ligaments providing structural support to the vagina/cervix/uterus complex. This ligament has been studied mainly with regards to its important function in the treatment of different diseases such as surgical repair for pelvic organ prolapse and radical hysterectomy for cervical cancer. However, the mechanical properties of the CL have not been fully determined, despite the important in vivo supportive role of this ligament within the pelvic floor. To advance our limited knowledge about the elastic and viscoelastic properties of the CL, we conducted three consecutive planar equi-biaxial tests on CL specimens isolated from swine. Specifically, the CL specimens were divided into three groups: specimens in group 1 (n = 7) were loaded equi-biaxially to 1 N, specimens in group 2 (n = 8) were loaded equi-biaxially to 2N, and specimens in group 3 (n = 7) were loaded equi-biaxially to 3N. In each group, the equi-biaxial loads of 1N, 2N, or 3N were applied and kept constant for 1200s three times. The two axial loading directions were selected to be the main in-vivo loading direction of the CL and the direction that is perpendicular to it. Using the digital image correlation (DIC) method, the in-plane Lagrangian strains in these two loading directions were measured throughout the tests. The results showed that CL was elastically anisotropic, as statistical differences were found between the mean strains along the two axial loading directions for specimens in group 1, 2, or 3 when the equi-biaxial load reached 1N, 2N, or 3N, respectively. For specimens in group 1 and 2, no statistical differences were detected in the mean normalized strains (or, equivalently, the increase in strain over time) between the two axial loading directions for each creep test. For specimens in group 3, some differences were noted but, by the end of the 3rd creep test, there were no statistical differences in the mean normalized strains between the two axial loading directions. These findings indicated that the increase in strain over time by the end of the 3rd creep test were comparable along these directions. The greatest mean normalized strain (or, equivalently, the largest increase in strain over time) was measured at the end of the 1st creep test (t=1200s), regardless of the equi-biaxial load magnitude or loading direction. Mean normalized strains during the 2nd and 3rd creep tests (t = 100, 600, and 1200s), along each loading direction, were not statistically different. Isochronal data collected at 1N, 2N, or 3N equi-biaxial loads indicated that the CL may be a nonlinear viscoelastic material. Overall, this experimental study offers new knowledge of the mechanical properties of the CL that can guide the development of better treatment methods such as surgical reconstruction for pelvic organ prolapse and radical hysterectomy for cervical cancer.

Architectural differences in the anterior and middle compartments of the pelvic floor of young-adult and postmenopausal females

The pelvic floor guards the passage of the pelvic organs to the exterior. The near-epidemic prevalence of incontinence in women continues to generate interest in the functional anatomy of the pelvic floor. However, due to its complex architecture and poor accessibility, the classical 'dissectional' approach has been unable to come up with a satisfactory description, so that many aspects of its anatomy continue to raise debate. For this reason, we opted for a 'sectional' approach, using the Chinese Visible Human project (four females, 21-35 years) and the Visible Human Project (USA; one female, 59 years) datasets to investigate age-related changes in the architecture of the anterior and middle compartments of the pelvic floor. The puborectal component of the levator ani muscle defined the levator hiatus boundary. The urethral sphincter complex consisted of a circular proximal portion (urethral sphincter proper), a sling that passed on the vaginal wall laterally to attach to the puborectal muscle (urethral compressor), and a circular portion that surrounded the distal urethra and vagina (urethrovaginal sphincter). The exclusive attachment of the urethral sphincter to soft tissues implies dependence on pelvic-floor integrity for optimal function. The vagina was circular at the introitus and gradually flattened between bladder and rectum. Well-developed fibrous tissue connected the inferior vaginal wall with urethra, rectum and pelvic floor. With eight-muscle insertions, the perineal body was a strong, irregular fibrous node that guarded the levator hiatus. Only loose areolar tissue comprising a remarkably well developed venous plexus connecting the middle and superior parts of the vagina with the lateral pelvic wall. The posterolateral boundary of the putative cardinal and sacrouterine ligaments coincided with the adventitia surrounding the mesorectum. The major difference between the young-adult and postmenopausal pelvic floor was the expansion of fat in between the components of the pelvic floor. We hypothesize that accumulation of pelvic fat compromises pelvic-floor cohesion, because the pre-pubertal pelvis contains very little fibrous and adipose tissue, and fat is an excellent lubricant.

Anatomic relationships of the pelvic autonomic nervous system in female cadavers: clinical applications to pelvic surgery

BACKGROUND

The integrity of the pelvic autonomic nervous system is essential for proper bowel, bladder, and sexual function.

OBJECTIVE

The purpose of this study was to characterize the anatomic path of the pelvic autonomic system and to examine relationships to clinically useful landmarks.

STUDY DESIGN

Detailed dissections were performed in 17 female cadavers. Relationships of the superior hypogastric plexus to aortic bifurcation and midpoint of sacral promontory were examined; the length and width of plexus was documented. Path and width of right and left hypogastric nerves were recorded. The origin and course of the pelvic splanchnic nerves were documented. Individual nerve tissue that contributed to the inferior hypogastric plexus was noted. Relative position of nerves to arteries, viscera, and ligaments was documented. In a subset of specimens, biopsy specimens were obtained to confirm gross findings by histologic analysis. Descriptive statistics were used for data analyses and reporting.

RESULTS

In all specimens, the superior hypogastric plexus was embedded in a connective tissue sheet within the presacral space, just below the peritoneum. In 14 of 17 specimens (82.4%), the plexus formed a median distance of 21.3 mm (range, 9-40 mm) below aortic bifurcation; in the remaining specimens, it formed a median distance of 25.3 mm (range, 20.5-30 mm) above bifurcation. In 58.8% of specimens, the superior hypogastric plexus was positioned to the left of midline. The median length and width of the plexus was 39.5 (range, 11.5-68) mm and 9 (range, 2.5-15) mm, respectively. A right and left hypogastric nerve was identified in all specimens and formed a median distance of 23 mm (range, 5-32 mm) below the promontory. The median width of the hypogastric nerve was 3.5 mm (range, 3-4.5 mm) on the right and 3.5 mm (range, 2-6.5 mm) on the left. The median distance from midportion of uterosacral ligament to the closest nerve branch was 0.5 mm (range, 0-4.5 mm) on right and 0 mm (range, 0-27.5 mm) on left. In all specimens, the inferior hypogastric plexus was formed by contributions from the hypogastric nerves and branches from S3 and S4. In 47.1% of hemipelvises, S2 branches contributed to the plexus. The sacral sympathetic trunk contributed to the plexus in 16 of 34 hemipelvises where this structure was identified. The inferior hypogastric plexus formed 1-3 cm lateral to the rectum and upper third of the vagina. From this plexus, 1-3 discrete branches coursed deep to the ureter toward the bladder. A uterine branch that coursed superficial to the ureter followed the ascending branch of the uterine artery. An S4 branch was found directly attaching to lateral walls of the rectum in 53% of specimens. Pelvic splanchnic nerves merged into the inferior hypogastric plexus on the lower and medial surface of the coccygeus muscle. Histologic analysis confirmed neural tissue in all tissues that were sampled.

CONCLUSION

Anatomic variability and inability to visualize the small caliber fibers that comprise the inferior hypogastric plexus grossly likely underlines the reasons that some postoperative visceral and sexual dysfunction occur in spite of careful dissection and adequate surgical technique. These findings highlight the importance of a discussion with patients about the risks that are associated with interrupting autonomic fibers during the preoperative consent.

Proposed definition of the vaginal cuff and paracolpium clinical target volume in postoperative uterine cervical cancer

PURPOSE

The aim of this study was to develop an appropriate definition for vaginal cuff and paracolpium clinical target volume (CTV) for postoperative intensity modulated radiation therapy in patients with uterine cervical cancer.

METHODS AND MATERIALS

A working subgroup was organized within the Radiation Therapy Study Group of the Japan Clinical Oncology Group to develop a definition for the postoperative vaginal cuff and paracolpium CTV in December 2013. The group consisted of 5 radiation oncologists who specialized in gynecologic oncology and a gynecologic oncologist. A comprehensive literature review that included anatomy, surgery, and imaging fields was performed and was followed by multiple discreet face-to-face discussions and e-mail messages before a final consensus was reached.

RESULTS

Definitions for the landmark structures in all directions that demarcate the vaginal cuff and paracolpium CTV were decided by consensus agreement of the working group. A table was created that showed boundary structures of the vaginal cuff and paracolpium CTV in each direction.

CONCLUSIONS

A definition of the postoperative cervical cancer vaginal cuff and paracolpium CTV was developed. It is expected that this definition guideline will serve as a template for future radiation therapy clinical trial protocols, especially protocols involving intensity modulated radiation therapy.

Paravaginal defect: anatomy, clinical findings, and imaging

INTRODUCTION AND HYPOTHESIS

The paravaginal defect has been a topic of active discussion concerning what it is, how to diagnose it, its role in anterior vaginal wall prolapse, and if and how to repair it. The aim of this article was to review the existing literature on paravaginal defect and discuss its role in the anterior vaginal wall support system, with an emphasis on anatomy and imaging.

METHODS

Articles related to paravaginal defects were identified through a PubMed search ending 1 July 2015.

RESULTS

Support of the anterior vaginal wall is a complex system involving levator ani muscle, arcus tendineus fascia pelvis (ATFP), pubocervical fascia, and uterosacral/cardinal ligaments. Studies conclude that physical examination is inconsistent in detecting paravaginal defects. Ultrasound (US) and magnetic resonance imaging (MRI) have been used to describe patterns in the appearance of the vagina and bladder when a paravaginal defect is suspected. Different terms have been used (e.g., sagging of bladder base, loss of tenting), which all represent changes in pelvic floor support but that could be due to both paravaginal and levator ani defects.

CONCLUSION

Paravaginal support plays a role in supporting the anterior vaginal wall, but we still do not know the degree to which it contributes to the development of prolapse. Both MRI and US are useful in the diagnosis of paravaginal defects, but further studies are needed to evaluate their use.

Microarray gene expression analysis of uterosacral ligaments in uterine prolapse

OBJECTIVES

Pelvic organ prolapse (POP) is a major health problem that impairs the quality of life with a wide clinical spectrum. Since the uterosacral ligaments provide primary support for the uterus and the upper vagina, we hypothesize that the disruption of these ligaments may lead to a loss of support and eventually contribute to POP.

DESIGN AND METHODS

In this study, we therefore investigated whether there are any differences in the transcription profile of uterosacral ligaments in patients with POP when compared to those of the control samples. Seventeen women with POP and 8 non-POP controls undergoing hysterectomy for benign conditions were included in the study. Affymetrix® Gene Chip microarrays (Human Hu 133 plus 2.0) were used for whole genome gene expression profiling analysis.

RESULTS

There was 1 significantly down-regulated gene, NKX2-3 in patients with POP compared to the controls (p=4.28464e-013). KIF11 gene was found to be significantly down-regulated in patients with ≥3 deliveries compared to patients with <3 deliveries (p=0.0156237). UGT1A1 (p=2.43388e-005), SCARB1 (p=1.19001e-006) and NKX2-3 (p=2.17966e-013) genes were found to be significantly down-regulated in the premenopausal patients compared to the premenopausal controls. UGT1A1 gene was also found to be significantly down-regulated in the post menopausal patients compared to the postmenopausal controls (p=0.0005).

CONCLUSION

This study provides evidence for a significant down-regulation of the genes that take role in cell cycle, proliferation and embryonic development along with cell adhesion process on the development of POP for the first time.

Micro-structural and Biaxial Creep Properties of the Swine Uterosacral-Cardinal Ligament Complex

The uterosacral ligament and cardinal ligament (USL/CL) complex is the major suspensory tissue of the uterus, cervix, and vagina. This tissue is subjected primarily to bi-axial forces in-vivo that significantly alter its structure and dimension over time, compromising its support function and leading to pelvic floor disorders. In this study, we present the first rigorous characterization of the collagen fiber microstructure and creep properties of the swine USL/CL complex by using scanning electron microscopy and planar biaxial testing in combination with three-dimensional digital image correlation. Collagen fiber bundles were found to be arranged into layers. Although the fiber bundles were oriented in multiple directions, 80.8% of them were aligned within ±45[Formula: see text] to the main in-vivo loading direction. The straightness parameter, defined as the ratio of the end-to-end distance of a fiber bundle to its length, varied from 0.28 to 1.00, with 95.2% fiber bundles having a straightness parameter between 0.60 and 1.00. Under constant equi-biaxial loads of 2 and 4 N, the USL/CL complex exhibited significant creep both along the main in-vivo loading direction (the parallel direction) and along the direction perpendicular to it (the perpendicular direction). Specifically, over a 120-min period, the mean strain increased by 20-34[Formula: see text] in the parallel direction and 33-41[Formula: see text] in the perpendicular direction. However, there was no statistically significant difference in creep strains observed after 120 min between the parallel and perpendicular directions for either the 2 or 4 N load case. Creep proceeded slightly faster in the perpendicular direction under the equi-biaxial load of 2 N than under the equi-biaxial load of 4 N ([Formula: see text]). It proceeded significantly faster in the parallel direction under the equi-biaxial loads of 2 N than under the equi-biaxial loads of 4 N ([Formula: see text]). Overall, our findings contribute to a greater understanding of the biomaterial properties of the USL/CL complex that is needed for the development of new surgical reconstruction methods and mesh materials for pelvic floor disorders.

3D finite element modeling of pelvic organ prolapse

OBJECTIVES

The purpose of this study is to develop a validated 3D finite element model of the pelvic floor system which can offer insights into the mechanics of anterior vaginal wall prolapse and have the ability to assess biomedical device treatment methods. The finite element results should accurately mimic the clinical findings of prolapse due to intra-abdominal pressure (IAP) and soft tissues impairment conditions.

METHODS

A 3D model of pelvic system was created in Creo Parametric 2.0 based on MRI Images, which included uterus, cervix, vagina, cardinal ligaments, uterosacral ligaments, and a simplified levator plate and rectum. The geometrical model was imported into ANSYS Workbench 14.5. Mechanical properties of soft tissues were based on experimental data of tensile test results from current literature. Studies were conducted for IAP loadings on the vaginal wall and uterus, increasing from lowest to extreme values.

RESULTS

Anterior vaginal wall collapse occurred at an IAP value corresponding to maximal valsalva and showed similar collapsed shape as clinical findings. Prolapse conditions exhibited high sensitivity to vaginal wall stiffness, whereas healthy tissues was found to support the vagina against prolapse. Ligament impairment was found to have only a secondary effect on prolapse.

Comparative histology of mouse, rat, and human pelvic ligaments

INTRODUCTION AND HYPOTHESIS

The uterosacral (USL) and cardinal ligaments (CL) provide support to the uterus and pelvic organs, and the round ligaments (RL) maintain their position in the pelvis. In women with pelvic organ prolapse (POP), the connective tissue, smooth muscle, vasculature, and innervation of the pelvic support structures are altered. Rodents are commonly used animal models for POP research. However, the pelvic ligaments have not been defined in these animals. In this study, we hypothesized that the gross anatomy and histological composition of pelvic ligaments in rodents and humans are similar.

METHODS

We performed an extensive literature search for anatomical and histological descriptions of the pelvic support ligaments in rodents. We also performed anatomical dissections of the pelvis to define anatomical landmarks in relation to the ligaments. In addition, we identified the histological components of the pelvic ligaments and performed quantitative analysis of the smooth muscle bundles and connective tissue of the USL and RL.

RESULTS

The anatomy of the USL, CL, and RL and their anatomical landmarks are similar in mice, rats, and humans. All species contain the same cellular components and have similar histological architecture. However, the cervical portion of the mouse USL and RL contain more smooth muscle and less connective tissue compared with rat and human ligaments.

CONCLUSION

The pelvic support structures of rats and mice are anatomically and histologically similar to those of humans. We propose that both mice and rats are appropriate, cost-effective models for directed studies in POP research.