Ka Lai Shek

Minimal criteria for the diagnosis of avulsion of the puborectalis muscle by tomographic ultrasound

Introduction and hypothesisPuborectalis avulsion is a likely etiological factor for female pelvic organ prolapse (FPOP). We performed a study to establish minimal sonographic criteria for the diagnosis of avulsion.MethodsWe analysed datasets of 764 women seen at a urogynecological service. Offline analysis of ultrasound datasets was performed blinded to patient data. Tomographic ultrasound imaging (TUI) was used to diagnose avulsion of the puborectalis muscle.ResultsLogistic regression modelling of TUI data showed that complete avulsion is best diagnosed by requiring the three central tomographic slices to be abnormal. This finding was obtained in 30% of patients and was associated with symptoms and signs of FPOP (P < 0.001). Lesser degrees of trauma (‘partial avulsion’) were not associated with symptoms or signs of pelvic floor dysfunction.ConclusionsComplete avulsion of the puborectalis muscle is best diagnosed on TUI by requiring all three central slices to be abnormal. Partial trauma seems of limited clinical relevance.

The effect of childbirth on hiatal dimensions.

OBJECTIVE: To estimate changes in levator hiatal dimensions after childbirth in women with and without ultrasonographically visible morphological abnormalities of the levator ani and to correlate those changes with delivery mode. METHODS: A total of 296 nulliparous women were recruited. They were examined with four-dimensional translabial ultrasonography at 36–38 weeks of gestation and at 3–4 months postpartum. Peripartal changes in levator hiatal dimensions were correlated with delivery data. RESULTS: Mean postpartum follow-up was 5.3 months (median 4.1, interquartile range 3.7 to 5.1). Of 212 women who returned for follow-up, 101 had had normal vaginal deliveries (48%), 31 vacuum/forceps (15%), and 80 cesarean deliveries (38%). After cesarean delivery, there was a decrease in the mean hiatal area on Valsalva maneuver of 8.5% (P=.005). Vaginal delivery without avulsion was associated with an increase of 6% (P=.035). In women with avulsion injury, hiatal area increased by 28% (P=.002). Mean postpartum hiatal area on Valsalva was 25.46 cm2 after vaginal delivery with avulsion, 22.61 cm2 without avulsion, and 19.13 cm2 in the cesarean delivery group. After avulsion, hiatal area on contraction also increased significantly (P<.001). CONCLUSION: Vaginal childbirth results in enlargement of the levator hiatus, especially after an avulsion. However, even without macroscopic levator trauma, there may be increased distensibility of the hiatus, which may be another mechanism leading to enlargement of the hiatus and pelvic organ prolapse. LEVEL OF EVIDENCE: II

The effect of levator avulsion on hiatal dimension and function.

OBJECTIVE Pelvic floor trauma as a result of vaginal childbirth can cause significant pelvic floor morbidity. In this observational study, we intended to define whether such trauma is associated with abnormal hiatal biometry and/or abnormal biomechanical properties of the levator muscle. STUDY DESIGN The datasets of 414 urogynecologic patients were assessed in a retrospective study. Patients underwent an interview, clinical examination, and 3-/4-dimensional pelvic floor ultrasound. All analysis was performed offline using proprietary software. Hiatal dimensions and strain were measured. RESULTS In 21.1% of parous women with a history of vaginal delivery, an avulsion of the levator muscle was diagnosed, and in 8.6% it was bilateral. The relative risk of abnormal distensibility was 3.5 (95% confidence interval, 1.7-6.5) in unilateral and 3.96 (95% confidence interval, 1.7-9.2) in bilateral avulsion. Avulsion increased muscle distensibility on Valsalva and reduced muscle shortening on pelvic floor muscle contraction. CONCLUSION Avulsion injury is associated with abnormal levator biometry and function.

Avulsion injury and levator hiatal ballooning: two independent risk factors for prolapse? An observational study.

Objective. To study whether avulsion and ballooning are independent risk factors for symptoms and/or signs of pelvic organ prolapse. Design. Retrospective analysis of data obtained in clinical practice. Setting. Tertiary urogynecology unit. Population. Seven hundred and sixty‐one consecutive women with symptoms of pelvic floor dysfunction. Methods. Evaluation included history, vaginal examination and four‐dimensional translabial ultrasound. Ultrasound analysis was performed off‐line, blinded against clinical data. Hiatal dimensions were measured at the plane of minimal hiatal dimensions. Puborectalis avulsion was identified using tomographic imaging. Main outcome measures. Symptoms and objective signs of prolapse (ICS POP‐Q stage 2+). Results. Owing to previous surgery 156 women were excluded, leaving 605, of whom 258 (43%) had prolapse symptoms. Significant prolapse (International Continence Society Prolapse Quantification System grade 2+) was identified as follows: cystocele in 222 (37%) women, rectocele in 159 (27%) and apical in 40 (8%), while 110 (18%) had an avulsion. There was a strong association between avulsion, hiatal ballooning and symptoms/signs of prolapse (p < 0.001). On multivariable backwards stepwise logistic regression, puborectalis avulsion was associated with an increased risk of symptoms and signs of prolapse, even after allowing for the degree of levator ballooning. The presence of avulsion did not modify the relation between hiatal area and symptoms of prolapse. Conclusions. Puborectalis avulsion injury and levator hiatal ballooning are independent risk factors for symptoms and signs of prolapse. The role of avulsion in the pathogenesis of prolapse is not fully explained by its effect on hiatal dimensions. It is likely that avulsion implies not only muscular trauma but also damage to structures impossible to assess clinically or by imaging, i.e. myofascial and connective tissue.

Can levator avulsion be predicted antenatally

OBJECTIVE We sought to determine whether antepartum prediction of major levator trauma is feasible. STUDY DESIGN A prospective longitudinal study was undertaken on 488 pregnant nulliparous women seen between 36-38 weeks and again 4 months after delivery. All underwent an interview and 4-dimensional transperineal ultrasound. Diagnosis of levator trauma (avulsion) on tomographic ultrasound was correlated with predelivery demographic variables and ultrasound parameters. RESULTS In all, 367 women returned for postpartum assessment after normal vaginal delivery (n = 187), vacuum/forceps (n = 54), and cesarean section (n = 126). Avulsion was diagnosed in 34 vaginally parous women (14%). Maternal age, family history of cesarean section, hiatal dimensions, levator muscle strain, bladder neck descent, and subpubic arch angle were not associated with avulsion. The only predictor identified was a lower body mass index (P = .005). CONCLUSION Antepartum prediction of major levator trauma may be difficult or impossible. Future studies should focus on modification of current obstetric practices and antepartum interventions applicable to the general population.

A simplified method for determining hiatal biometry

Introduction:  The levator hiatus is the largest potential hernial portal in the human body. Its dimensions are measured in the axial plane and are strongly associated with female pelvic organ prolapse. We aimed to compare two commonly used methods for measuring hiatal dimensions.

The use of 3‐dimensional ultrasound of the pelvic floor to predict recurrence risk after pelvic reconstructive surgery

Female pelvic organ prolapse is a common condition. Prolapse recurrence following surgical treatment is a significant clinical issue. The aim of this study was to determine risk factors for recurrence, attempting to improve clinical practice by allowing better patient selection prior to surgery.

Can ballooning of the levator hiatus be determined clinically

OBJECTIVE The objective of the study was to determine whether genital hiatus (gh) and perineal body (pb), measured using the pelvic organ prolapse quantification system of the International Continence Society, are predictive of an abnormally distensible levator hiatus on ultrasound and of objective prolapse and/or prolapse symptoms. STUDY DESIGN The design of the study included datasets of 188 urogynecology patients assessed in a cross-sectional retrospective study. RESULTS Gh and pb, as well as gh plus pb, were strongly associated with symptoms and signs of prolapse and with hiatal area on ultrasound. The sum of gh and pb was superior in predictive performance to individual measures for symptoms (P < .001) and signs of prolapse (P < .001). Gh plus pb equaled the hiatal area on ultrasound (area under the curve, 0.886; 95% confidence interval, 0.828-0.945 vs 0.867; 95% confidence interval, 0.808-0.926) for predicting objective prolapse. Optimal sensitivity (80%) and specificity (81%) was reached with a cutoff of 7 cm for gh plus pb. CONCLUSION A cutoff of 7 cm for gh plus pb measured on Valsalva is proposed as a clinical definition of excessive levator hiatal distensibility.

Mesh contraction: myth or reality?

OBJECTIVE Mesh implants are widely used in surgery for female pelvic organ prolapse. Mesh shrinkage is thought to be common and caused by immunological processes. In this longitudinal study, we examined mesh dimensions at 2 time points after implantation. STUDY DESIGN We analyzed translabial 4-dimensional ultrasound (US) volume datasets of women seen 3-52 months after anterior compartment mesh. Datasets of first and last postoperative appointments were analyzed, with the operator blinded against all other data. RESULTS Forty women were assessed at least twice, comprising 59.6 woman-years. Thirty-seven of 40 (93%) were satisfied at their last appointment. Eighteen of 40 considered themselves cured, and 18 of 40 felt improved. Objective recurrence (cystocele stage 2 or greater) was seen in 16 of 40. Midsagittal mesh length increased significantly (35.8 vs 32.7; P = .006), and coronal mesh diameters increased nonsignificantly (37.4 vs 36.6 mm; P = .44). CONCLUSION Over an observation period of almost 60 woman-years, we found no evidence of mesh contraction.

The urethral motion profile: A novel method to evaluate urethral support and mobility

Background: Urethral hypermobility is one of the theories developed to explain stress urinary incontinence. Traumatic damage to urethral supports during vaginal childbirth may be an important contributor.