Correlation between anal sphincter defects and anal incontinence following obstetric sphincter tears: assessment using scoring systems for sonographic classification of defects

Detection of obstetric anal sphincter injuries using machine learning-assisted impedance spectroscopy: a prospective, comparative, multicentre clinical study

To evaluate the clinical performance and safety of the ONIRY system for obstetric anal sphincter injuries (OASI) detection versus three-dimensional endoanal ultrasound (EAUS). A prospective, comparative, multicentre, international study. Poland, Czechia, Slovakia, and Spain. 152 women between the first moments up to 8 weeks after vaginal delivery. Participants underwent EAUS and were allocated to groups based on OASIS classification: A (no perineal tear), B (1st or 2nd degree tear), or C (3rd or 4th degree, anal sphincters affected). Electric impedance was measured in the anal canal using the ONIRY system. The primary endpoint was the diagnostic outcome of impedance spectroscopy versus EAUS. Adverse events were collected. Part II involved in silico modelling and 10-time 10-fold cross-validation for automated analysis. Accuracy, sensitivity, and specificity. 30 women were allocated to group A, 61 to group B, and 61 to group C. The diagnostic outcome was determined for 147 participants. The accuracy, sensitivity, and specificity of the ML-assisted impedance spectroscopy were 87.0 ± 0.5%, 90.6 ± 2.0%, and 84.6 ± 1.9%, respectively, compared with EAUS. After data cleaning, the performance metrics of the proposed final ML model for ONIRY were: 90.0 ± 0.4%, 90.0 ± 1.2%, and 90.0 ± 0.7%, respectively. No adverse device effects or deficiencies were observed. By enabling early identification of sphincter injuries, ML-assisted impedance spectroscopy facilitates timely diagnosis and intervention, potentially reducing long-term complications such as faecal incontinence. Its rapid, bedside application in obstetric settings supports immediate postpartum care, complementing digital rectal examination and optimizing clinical decision-making.

Retrospective analysis of 3a obstetric anal sphincter injury repairs in a teaching hospital: Subjective and objective outcomes

INTRODUCTION

The Royal College of Obstetricians and Gynaecologists (RCOG) recommends offering elective caesarean sections (CS) for subsequent deliveries to obstetric anal sphincter injury (OASI) patients with anorectal dysfunction, or abnormal endoanal ultrasonography (EA USS), and/or anal manometry (AM). (1) Asymptomatic OASI patients however, are not always offered EA USS or AM due to limited access to diagnostic resources across the United Kingdom, particularly those with 3a tears. This paper reviews subjective and objective outcomes in women with 3a tears and aims to add to the body of literature supporting good practice and management.

OBJECTIVES

Identify the incidence of defects in patients with 3a tears following a primary repair and compare the rate and extent of defects found on EA USS between symptomatic and asymptomatic women.

STUDY DESIGN

We performed a retrospective study of 69 women following primary repair of 3a OASI tears in a tertiary referral perineal clinic between January 2020 and December 2022. Symptoms were evaluated using the St Mark's Score for anal incontinence (SMI) and Starck score for defects on EA USS. Findings were analyzed using R Foundation Statistical Software (version 4.2.2, 2022).

RESULTS

Out of the total, 42 % (29/69) had defects on EA USS and 30 % (21/69) of women were symptomatic. Thirty eight percent (18/48) of asymptomatic women were noted to have defects compared with 52 % (11/21) of symptomatic patients. Majority of defects were situated in the upper and mid anal canal (69 %) either as <1 hr or >3 hr hypoechoic areas. There was no significant difference in defect rate (X2 = 2.06, p = 0.15) or Starck score (2.23 v 1.53, p = 0.22) between the two groups. However those delivered by forceps (p = 0.004) and of Asian ethnicity (p = 0.01) were more likely to be symptomatic.

CONCLUSION

EA USS should be offered to all patients following an OASI, as symptoms alone are not predictive of anorectal compromise in structure and/or function. Asymptomatic patients with 3a tears should be informed that there is up to a 40% chance of finding a defect on EA USS.

A UK wide survey of general surgeons' experience of the primary repair of obstetric anal sphincter injuries

AIM

Obstetric anal sphincter injuries (OASIs) are associated with devastating consequences, mainly faecal incontinence. A timely and correct repair is necessary to reduce the risk of maternal morbidity. The aim was to explore the experience and practice of on-call general surgeons in the acute repair of OASIs.

METHOD

A cross-sectional, observational questionnaire study was performed. Registrars and consultants participating in an emergency general surgical rota in the UK were included. A 33-item questionnaire was disseminated over a 9-month period from April 2023. A descriptive, thematic analysis of the data was undertaken.

RESULTS

In all, 310 responses were analysed. 42.3% of colorectal respondents (of which 29% were pelvic floor specialists), 24.3% of general surgeons, 16.7% of hepato-biliary surgeons and 13.7% of upper gastrointestinal surgeons were contacted to assist with an acute repair. Of those contacted, 52.3% typically assisted with a 3C or 4 tear, 54.2% received no training and 95.5% performed less than three acute repairs in the previous year. 57.6% of all respondents were not confident at all in the repair of these injuries, 55% highlighted a lack of experience and 36% mentioned a curricular gap.

CONCLUSION

Surgeons may be called to assist with an acute OASI repair, particularly in cases of severe anatomical disruption. This occurs infrequently. There is a lack of consensus as to who is responsible for these injuries. Obstetricians have structured training in both the recognition and repair of these injuries. This paper serves to highlight the lack of training for surgeons who report doing this surgery despite lacking the required competences.

Follow up of women after obstetric anal sphincter injuries (OASI)-What is the role of anorectal testing?

AIMS

To evaluate the benefit of performing anorectal studies on all women following primary obstetric anal sphincter injury (OASI) repair over performing them on symptomatic women only.

METHODS

Women who attended perineal clinic between 2007 and 2020 underwent symptom assessment and anorectal studies at 6 weeks and 6 months postpartum. Anorectal studies including endo anal ultrasound (EAUS) and anal manometry (AM) were performed. The anorectal studies of symptomatic women who were the case group, were compared with asymptomatic women who were the control group.

RESULTS

A total of 1348 women were seen in the perineal clinic over 13 years. A total of 454 (33.7%) women were symptomatic. A total of 894 (66.3%) women were asymptomatic. A total of 313 (35%) asymptomatic women had two abnormal anorectal studies, 274 (31%) had abnormal AM alone, and 86 (9.6%) had abnormal EAUS alone. A total of 221 (24.7%) asymptomatic women had normal anorectal studies.

CONCLUSION

Almost 70% of women were asymptomatic 6 months following primary OASI repair. Most had at least one abnormal anorectal study result. Selectively performing anorectal tests on symptomatic women would not identify asymptomatic women at risk of future faecal incontinence following further vaginal birth. Without anorectal study results, women would not receive accurate counseling about the risks of vaginal birth. Anorectal studies should be offered to all women following OASI where resources allow.

Risk Factors for Anal Continence Impairment Following a Second Delivery after a First Traumatic Delivery: A Prospective Cohort Study

Postpartum anal incontinence is common. After a first delivery (D1) with perineal trauma, follow-up is advised to reduce the risk of anal incontinence. Endoanal sonography (EAS) may be considered to evaluate the sphincter and in case of sphincter lesions to discuss cesarean section for the second delivery (D2). Our objective was to study the risk factors for anal continence impairment following D2. Women with a history of traumatic D1 were followed before and 6 months after D2. Continence was measured using the Vaizey score. An increase ≥2 points after D2 defined a significant deterioration. A total of 312 women were followed and 67 (21%) had worse anal continence after D2. The main risk factors for this deterioration were the presence of urinary incontinence and the combined use of instruments and episiotomy during D2 (OR 5.12, 95% CI 1.22-21.5). After D1, 192 women (61.5%) had a sphincter rupture revealed by EAS, whereas it was diagnosed clinically in only 48 (15.7%). However, neither clinically undiagnosed ruptures nor severe ruptures were associated with an increased risk of continence deterioration after D2, and cesarean section did not protect against it. One woman out of five in this population had anal continence impairment after D2. The main risk factor was instrumental delivery. Caesarean section was not protective. Although EAS enabled the diagnosis of clinically-missed sphincter ruptures, these were not associated with continence impairment. Anal incontinence should be systematically screened in patients presenting urinary incontinence after D2 as they are frequently associated.

Underdiagnosis of internal anal sphincter trauma following vaginal delivery

OBJECTIVE

Damage to the anal sphincter during childbirth remains the leading cause of fecal incontinence in women. Defects in the internal (IAS) or external anal sphincter, alongside symptoms and sphincter tone, will generally dictate the suggested mode of delivery in any successive pregnancy. This study aimed to examine using endoanal ultrasonography the prevalence of IAS damage in women referred with Grade-3a or -3b obstetric anal sphincter injury (OASI) in a tertiary-referral perineal clinic.

METHODS

This was a retrospective observational study of all women referred to a tertiary-referral perineal clinic after primary repair of OASI (Grade 3a-c, 4) diagnosed for the first time following vaginal delivery between January 2016 and December 2019, inclusive. Women were assessed using the Wexner bowel continence questionnaire, digital examination of sphincter tone and endoanal ultrasound. Injuries in each sphincter were classified as a scar (≤ 30°) or defect (> 30-90° or > 90°) on endoanal imaging in the axial plane.

RESULTS

In total, 615 women were referred following primary repair of OASI. Sonographic evidence of damage to the IAS was seen in 9.1% (46/506) of women diagnosed with a Grade-3a/3b injury. In women referred with a Grade-3a/3b tear, symptom scores were statistically higher (P = 0.025) in those with an IAS defect > 30° compared to those with an intact or scarred IAS, although the median score was zero in both groups. The proportion of women in each group with severe symptoms (score > 9) was similar (2.6% vs 6.5%; P = 0.148). Among women referred with a Grade-3a/3b tear, sphincter tone was reduced more frequently in those with a defect of the IAS than in those with an intact or scarred IAS (52.2% vs 11.7%; odds ratio, 8.14 (95% CI, 4.26-15.67); P < 0.001). Regardless of the reason for referral, women with reduced sphincter tone on rectal examination were four times as likely to have had an IAS defect > 30° than were those with normal resting tone (risk ratio, 4.58 (95% CI, 3.25-6.45); P < 0.001).

CONCLUSIONS

One in 11 women diagnosed with a Grade-3a or -3b tear have evidence of damage to their IAS on endoanal ultrasound. Damage to this muscle is linked to fecal incontinence in women and can have a significant impact on the planning of any future deliveries. This study highlights the importance of established perineal clinics with access to ultrasound. Nonetheless, if reduced sphincter tone is felt on rectal examination, a clinician should have a high index of suspicion for an occult IAS injury. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Comparison of diagnostic criteria for significant anal sphincter defects between endoanal and transperineal ultrasound

OBJECTIVE

To evaluate the agreement between three-dimensional endoanal ultrasound (EAUS) and four-dimensional transperineal ultrasound (TPUS) in measuring anal sphincter defect angle.

METHODS

This was a secondary analysis of the PERINEAL study, which evaluated the effect of perineal wound infection on anal sphincter integrity. Women were reviewed once a week, until their perineal wound had healed or for up to a maximum of 16 weeks. At each visit, both EAUS and TPUS (the latter at rest and on maximum pelvic floor muscle contraction (PFMC)) were performed to evaluate the presence of external (EAS) and internal (IAS) anal sphincter defect and measure the defect size. The largest angle size of a defect at the same sphincter level was analyzed. A defect was deemed significant if it was > 30°. Kappa coefficient (κ), intraclass correlation coefficient and standard error of measurement (SEM) were calculated, using EAUS as the reference standard.

RESULTS

In 73 women scanned at weekly intervals, a total of 250 EAUS and 250 TPUS scans were performed. An EAS defect was found in 55 (22.0%) EAUS images and 47 (18.8%) TPUS images. An IAS defect was found in 26 (10.4%) images on both modalities. There was excellent agreement (κ = 0.87) between TPUS and EAUS in diagnosing the presence of an EAS defect and perfect agreement (κ = 1.00) in diagnosing the presence of an IAS defect. TPUS performed at rest had poor and moderate agreement with EAUS in measuring EAS and IAS defect size, respectively, with respective SEMs of ± 16.1° and ± 27.9°. TPUS performed during maximum PFMC had poor and moderate agreement with EAUS in measuring EAS and IAS defect size, respectively, with respective SEMs of ± 16.5° and ± 26.4°. Based on the SEMs, if the diagnostic cut-off of 30° for defect size on TPUS was used, an incorrect diagnosis of significant EAS defect could occur in approximately 9-36% of women and an incorrect diagnosis of a significant IAS defect could occur in approximately 4-15% of women, using EAUS as the reference.

CONCLUSIONS

This is the first study to compare directly anal sphincter defect angle measurements obtained on EAUS and TPUS. A cut-off angle of 30° should not be used for the diagnosis of a significant residual anal sphincter defect during TPUS examination. Further research is required to determine the optimal defect cut-off angle for TPUS. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

3D Ultrasound in Pelvic Floor: Is It Useful as a Prognostic Tool in Type of Labor Development and Subsequent Pelvic Floor Diseases?

The objective of our study is to determine the thickness of the pubovisceral fasciculus of the levator ani muscle and the area of the genital hiatus by means of three-dimensional perineal ultrasound, in pregnant women in the 2nd trimester, and to analyze the related maternal, perinatal and postpartum clinical variables. Furthermore, to compare the results of our study with two similar series previously published. An observational, prospective study of pelvic floor ultrasound was carried out, performed at week 20, whose delivery was attended in the obstetrics service of the Hospital General Universitario Gregorio Marañón de Madrid (HGUGM), during the period of August from 2021 to June 2022. Maternal, ultrasound, perinatal and postpartum clinical variables were collected from each participant. During the study period, a total of 54 patients were included in it. The mean gestational age at which the ultrasound was performed was 19.81 ± 0.91 weeks. In relation to the ultrasound variables, the mean thickness of the pubovisceral muscle was 0.87 ± 0.13 cm (95% CI, 0.64-1.38 cm), while, in the plane of minimum dimension of the genital hiatus, the hiatal area at rest was 13.41 ± 3.22 (95% CI, 4.60-18.78) cm2. There is a significant correlation between the age of pregnant women (over 35 years of age) and the increase in the area of the genital hiatus (r = 0.295, p = 0.031). 3D ultrasound of the pelvic floor performed at week 20 of gestation can to be an effective, non-invasive, reproducible and cheap tool in the prognosis of the development of labor and of possible subsequent perineal dysfunctions.

Is there a role for transperineal ultrasound imaging of the anal sphincter immediately after primary repair of third degree tears?

OBJECTIVE

When obstetric anal sphincter injuries are identified, it is crucial that the defects are repaired appropriately to achieve a better outcome. Although the presence of an intact anal sphincter is not the sole mechanism for maintaining continence, and not all women with an anal sphincter defect are symptomatic, there is an association between sphincter defects and anal incontinence. Our aim was to evaluate whether transperineal ultrasound (TPUS) is useful in assessing anal sphincter integrity immediately following primary repair of obstetric anal sphincter injuries (OASIs).

STUDY DESIGN

This is a prospective observational study of women who sustained OASIs during their first vaginal delivery. Three dimensional (3D) TPUS was performed immediately after repair of OASIs to identify anal sphincter defects. A repeat TPUS was performed 12 weeks following repair.

RESULTS

21 women sustained OASIs of whom 20 (95%) attended follow up. Eight (40%) had a grade 3a tear and 12 (60%) a 3b tear. 8/20 (40%) women had residual external anal sphincter (EAS) defects identified by TPUS immediately after repair. Of these eight defects, six (75%) persisted at 12 weeks postpartum. No new defects were seen at follow up among the twelve women in whom no defect was seen immediately following the repair. Six residual EAS defects were found at 12 weeks postpartum. An EAS defect at 12 weeks postpartum was associated with anal incontinence (p = 0.04). Women with 3b tears were more likely to have anal incontinence (AI) and residual sonographic EAS defects when compared with 3a tears but this was not statistically significant.

CONCLUSIONS

Women who had no TPUS defect detected immediately following primary repair of OASIs, remained as such at 12 weeks postpartum. Of those in whom a defect was seen immediately after repair, it persisted in 75% of cases at 12 weeks. We believe that the value of TPUS immediately after repair appears to be limited and would need to be defined if it were to be considered for routine practice. Further research on its role immediately after repair of major tears (Grade 3C/4) is needed. In addition, performing ultrasound would require widespread training of obstetricians to develop expertise. This highlights the importance of adequate training of obstetricians in OASI repair.

Under-classified obstetric anal sphincter injuries

INTRODUCTION AND HYPOSTHESIS

Obstetric anal sphincter injuries (OASIs) that are missed at delivery can have long-term consequences. OASIs that are under-classified at delivery are likely to be inadequately repaired, resulting in a persistent anal sphincter defect. We aimed to identify women who have persistent defects on endoanal ultrasound, inconsistent with the original diagnosis, and compare the effect on St Mark's incontinence scores (SMIS). We also aimed to look for changes in numbers of under-classification over time.

METHODS

Records of women attending a perineal clinic who had endoanal ultrasound from 2012 to 2020 were reviewed. Women who had a modified Starck score implying a defect greater than the classification [indicated by the depth of external anal sphincter or internal anal sphincter (IAS) defect] at delivery were identified.

RESULTS

A total of 1056 women with a diagnosis of 3a or 3b tears were included. Of these, 120 (11.36%) were found to have a defect greater than the original diagnosis and therefore were incorrectly classified at delivery. Women who had a 3b tear diagnosed at delivery, but had an IAS defect, had a significantly higher SMIS (p < 0.01). When comparing two 4-year periods, there was a significant improvement in the diagnosis of IAS tears.

CONCLUSION

Some women with OASIs that have under-classified OASIs are associated with worse anorectal symptoms. This is likely because of an incomplete repair. Some improvement in diagnosis of IAS tears has been noted. We propose improved training in OASIs can help reduce the number of incorrectly classified tears and improve repair.

Critical appraisal of international guidelines for the management of fecal incontinence in adults: is it possible to define what to do in different clinical scenarios?

Fecal incontinence (FI) is a complex often multifactorial functional disorder which is associated with a significant impact on patients’ quality of life. There is a broad spectrum of symptoms, and degrees of severity and diverse patient backgrounds. Several treatment algorithms from different professional societies and experts are available in the literature. However, no consensus has been reached on several aspects of FI management. We performed a critical review of the most recently published guidelines on FI, emphasising the lack of consensus, highlighting specific topics mentioned in each of the guidelines that are not covered in the others and defining the treatment proposed in different clinical scenarios.

Which factors are associated with anal incontinence after obstetric anal sphincter injury?

OBJECTIVES

Obstetric anal sphincter injury (OASI) is an important factor in the etiology of anal incontinence. This study aimed to evaluate whether anal sphincter defects, levator avulsion or levator ballooning after OASI are associated with severity of anal incontinence. Furthermore, we evaluated whether factors such as constipation and altered stool consistency are associated with symptoms of incontinence after OASI.

METHODS

In this multicenter prospective observational cohort study, women with OASI were invited to participate at least 3 months after primary repair. All women completed validated questionnaires, including St Mark's incontinence score, Bristol stool scale (BSS) and Cleveland clinic constipation score (CCCS), and underwent four-dimensional (4D) transperineal ultrasound for assessment of the levator ani muscle and anal sphincter.

RESULTS

In total, 220 women were included. Median follow-up was 4 months (range, 3-98 months). Univariate linear regression analysis showed an association of St Mark's incontinence score with a residual defect of the external anal sphincter (EAS) (β, 1.55 (95% CI, 0.04-3.07); P = 0.045), higher parity (β, 0.85 (95% CI, 0.02-1.67); P = 0.046), BSS (β, 1.28 (95% CI, 0.67-1.89); P < 0.001) and CCCS (β, 0.36 (95% CI, 0.18-0.54); P < 0.001). However, multivariate linear regression found an association of St Mark's incontinence score only with BSS (β, 1.50 (95% CI, 0.90-2.11); P < 0.001) and CCCS (β, 0.46 (95% CI, 0.29-0.63); P < 0.001).

CONCLUSIONS

Residual defects of the EAS, detected on 4D transperineal ultrasound, are associated with severity of anal incontinence symptoms measured using St Mark's incontinence score 4 months after OASI repair. Furthermore, clinical factors such as constipation and altered stool consistency appear to influence this association and may therefore play a more important role in clinical management. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.

Postpartum ultrasound for the diagnosis of obstetrical anal sphincter injury

This review presents the available data on the diagnosis of obstetrical anal sphincter injury by postnatal ultrasound imaging. There is increasing evidence that anal sphincter tears are often missed after childbirth and, even when diagnosed, often suboptimally repaired, with a high rate of residual defects after reconstruction. Even after postpartum diagnosis and primary repair, 25% to 50% of patients will have persistent anal incontinence. As clinical diagnosis may fail in the detection and classification of obstetrical anal sphincter injury, the use of imaging has been proposed to improve the detection and treatment of these lacerations. Notably, 3-dimensional endoanal ultrasound is considered the gold standard in the detection of obstetrical anal sphincter injury, and recently, 4-dimensional transperineal ultrasound, commonly available in obstetrical and gynecologic settings, has proven to be effective as well. Avoidance of forceps delivery when possible, performance of a rectal examination after vaginal delivery and before repair of any severe perineal tear, and offering sonographic follow-up at 10 to 12 weeks after vaginal delivery in high-risk women (maternal age of ≥35 years, vaginal birth after cesarean delivery, forceps, prolonged second stage of labor, overt obstetrical anal sphincter injury, shoulder dystocia, and macrosomia) may help reduce morbidity arising from anal sphincter tears.

Can ultrasound 10 days after obstetric anal sphincter injury predict anal incontinence at long-term follow-up?

INTRODUCTION AND HYPOTHESIS

The objective was to investigate whether endoanal ultrasound (EAUS) performed 10 days after a primary repaired obstetric anal sphincter injury (OASIS) can predict the severity of anal incontinence (AI) in the long term.

METHODS

This prospective cohort study included women with a primary repaired 3b-degree tear, 3c-degree tear or fourth-degree tear at Aarhus University Hospital, Denmark, from 1 September 2010 to 31 May 2011. Clinical assessment and EAUS were performed on day 2, day 10, and day 20 after delivery. Functional outcomes were assessed using a questionnaire at the time of all clinical visits and at the long-term follow-up, 7 years after delivery. AI was graded according to the Wexner score and EAUS defects were graded according to the Starck score.

RESULTS

Ninety-six out of 99 women consented to participate. Five women had a secondary sphincter repair and were subsequently excluded from follow-up. Fifty-seven women underwent both EAUS 10 days after delivery and answered the long-term follow-up questionnaire. Median follow-up time was 7.7 years (IQR 7.4-7.8). Mean Wexner score was 4.4 ± 4.8 10 days after delivery and 2.5 ± 2.8 at follow-up; thus, the Wexner score improved over time (p = 0.01). Ultrasound sphincter defects were found in 82.6% of the women. Mean Starck score was 3.0 ± 1.8. The risk of AI was 0% (95% CI 0.0-30.8) if the Starck score was 0. No correlation was found between the Starck score and the Wexner score at follow-up.

CONCLUSIONS

We found that performing EAUS in the puerperium following OASIS has limited value in predicting long-term AI.

Anal Sphincter Length as Determined by 3-Dimensional Endoanal Ultrasound and Anal Manometry: A Study in Healthy Nulliparous Women

OBJECTIVES

The normal female external anal sphincter (EAS) is shorter anteriorly than laterally and posteriorly. Furthermore, the thickness of the very proximal part of the circular EAS is thinner than 50% of the lateral and posterior EAS thickness. The extent of these features is not fully explored. The aim of this prospective study was to assess the normal anal sphincter with 3-dimensional (3D) endoanal ultrasound (EAUS) and to relate 3D EAUS length measurements to sphincter length determined by anal manometry.

METHODS

Healthy premenopausal nulliparous women underwent anal manometry and 3D EAUS examinations. Two experienced colorectal surgeons independently assessed all scans, blinded to any patient data.

RESULTS

A total of 43 women were included. Four scans were incomplete and excluded from the analysis. Interobserver agreement was fair to very good for the various length measurements. The mean length from the distal border of the puborectal muscle to the very proximal border of the anterior EAS (the anterior gap) was 4.4 (95% confidence interval, 3.9-4.9) mm, whereas the length to the level where the anterior EAS thickness was at least 50% of the lateral and posterior EAS thickness was 7.2 (95% confidence interval, 6.5-7.9) mm. Manometric sphincter length at rest did not correlate with any 3D EAUS length measurements.

CONCLUSIONS

In the normal anterior female anal canal, the EAS is not present or appears with less than 50% of the thickness of the lateral and posterior EAS for the first 7.2 mm below the distal border of the puborectal muscle.

Residual Defects of the Anal Sphincter Complex Following Primary Repair of Obstetrical Anal Sphincter Injuries at a Large Canadian Obstetrical Centre

OBJECTIVES

To determine the rates of residual anal sphincter defect following primary repair of obstetrical anal sphincter injury (OASIS), and to assess symptomatology in these patients.

METHODS

A retrospective observational study of patients who underwent primary repair of an OASIS sustained at Mount Sinai Hospital from January 2016 to June 2017. Records were reviewed for demographic and obstetrical data, symptoms of anal incontinence (AI), and the results of endoanal ultrasonography (EA-US).

RESULTS

One hundred and one women sustained an OASIS during the study period, of whom 53 had EA-US performed at Mount Sinai Hospital; 4 women were excluded from this analysis. There were 42 third-degree tears and 7 fourth-degree tears. EA-US revealed residual defects in 22 patients with third-degree tears and 5 patients with fourth-degree tears (52% vs. 71%; P = 0.44).  Twelve patients with third-degree tears and 4 patients with fourth-degree tears reported AI (29% vs. 57%; P = 0.20). EA-US revealed no evidence of a tear in 14 patients clinically diagnosed with third-degree tears and 1 patient clinically diagnosed with a fourth-degree tear (33% vs. 14%).

CONCLUSION

These data demonstrate deficiencies in diagnosis and repair of OASIS. Continued training for health care providers on identification and effective repair of OASIS may improve outcomes for women who experience this complication.

Establishing a peripartum perineal trauma clinic: a narrative review

INTRODUCTION AND HYPOTHESIS

Obstetric anal sphincter injury (OASI) is not rare, and its consequences are multiple and potentially severe, especially for young women. Some dedicated perineal clinics have been established to improve the management of OASI. Despite their obvious importance, these specific clinics are underrepresented and underdeveloped. The objectives of this review are to explore various options for developing a peripartum perineal clinic and to compare the different practices regarding the mode of delivery for subsequent pregnancies after an OASI.

METHODS

This narrative review covers information from patients' questionnaires specific to anal incontinence, anal physiology assessment, pelvic floor and anal sphincter imaging, and the arguments for choosing the mode of delivery after an OASI.

RESULTS

This review highlights the extensive range of practices regarding the delivery mode after an OASI throughout national professional organizations and experienced perineal clinics.

CONCLUSION

This review summarizes the different choices in developing a perineal clinic to facilitate their development in promoting health care and education specific for peripartum women concerning the perineal consequences of delivery for obstetrician-gynaecologists, family doctors, and residents.

Transperineal anal sphincter complex evaluation after obstetric anal sphincter injuries: With or without tomographic ultrasound imaging technique?

OBJECTIVES

"Significant" obstetric anal sphincter injuries (OASIS) have been defined as visible defects of at least 30° in at least 4/6 slices using tomographic ultrasound imaging (TUI) with transperineal ultrasound (TPUS). The objective of this study was to assess if TUI is mandatory for the evaluation of OASIS.

METHODS

Patients with a history of OASIS were evaluated by performing 3D-endoanal ultrasound (EAUS) and 3D-TPUS with and without TUI. Any damage to the internal (IAS) or external (EAS) anal sphincters was recorded and scored using the Starck's and the Norderval's systems. Intraobserver and inter-techniques correlations were calculated.

RESULTS

From September 2012 to May 2015, 63 women, mean age 32.5 ± 4.6 years, with OASIS (3a: 26 pts., 41.3 %; 3b: 26 pts., 41.3 %; 3c: 6 pts., 9.5 %, 4: 4 pts., 6.3 %, "button hole" tear: 1 pt., 1.6 %). Inter-technique and intraobserver correlations were excellent (TUI: k = 0.9; sweeping technique: k = 0.85; EAUS: k = 0.9) in determining OASIS. Using the Starck's Score, excellent correlation was found for both TPUS modalities (TUI: k = 0.86; sweeping technique: k = 0.89). However, for the different individual parameters, the correlation was moderate for EAS depth (TUI: k = 0.44; sweeping technique: k = 0.5) and good for IAS depth (TUI: k = 0.7; sweeping technique: k = 0.78). Similar results were found using the Norderval's classification.

CONCLUSIONS

OASIS can be assessed by TPUS without TUI technique, dragging the rendered box and following the anal canal from the anal verge to the anorectal junction in the longitudinal plane and describing findings.

Effect of a subsequent pregnancy on anal sphincter integrity and function after obstetric anal sphincter injury (OASI)

Introduction and hypothesis

Endoanal ultrasound (EAUS) and anal manometry are used in the assessment women with a history of obstetric anal sphincter injury (OASI), both postpartum and in a subsequent pregnancy, to aid counselling regarding mode of delivery (MOD).

Methods

A prospective observational study between 2012 to 2020 was completed. Women were reviewed 3 months postpartum following OASI and in the second half of a subsequent pregnancy. Anorectal symptoms were measured using the validated St Mark’s Incontinence Score (SMIS: asymptomatic to mild symptoms = ≤ 4). Anal manometry (incremental maximum squeeze pressure [iMSP: normal = > 20 mmHg]) and EAUS (abnormal = sphincter defect > 1 h in size) were performed.

Results

One hundred forty-six women were identified and 67.8% had an anal sphincter defect ≤ 1 h in size postnatally. In those with a defect ≤ 1 h, postpartum mean iMSP and SMIS significantly improved in a subsequent pregnancy (p = 0.04 and p = 0.01, respectively). In women with a defect > 1 h, there was no significant difference between the mean iMSP or SMIS score postnatally compared to a subsequent pregnancy. At both time points, significantly more women had an anal sphincter defect ≤ 1 h and SMIS of ≤ 4 (p = 0.001 and p < 0.001 respectively) compared to those with a defect < 1 h. In addition, significantly more women had an anal sphincter defect ≤ 1 h and iMSP ≥ 20 mmHg (p < 0.001). Overall, out of the 146 women included in this study, 76 (52.1%) with a defect ≤ 1 h also had an iMSP ≥ 20 mmHg and SMIS ≤ 4 at 3 months postpartum.

Conclusions

Women who remain asymptomatic with normal anal manometry and no abnormal sphincter defects on EAUS postnatally do not need to have these investigations repeated in a subsequent pregnancy and can be recommended to have a vaginal delivery. If our protocol was modified, over half of the women in this study could have had their MOD recommendation made in the postnatal period alone.

How comparable is clinical grading of obstetric anal sphincter injury with that determined by four-dimensional translabial ultrasound?

OBJECTIVES

To evaluate the agreement between grading of obstetric anal sphincter injuries (OASI) on translabial ultrasound (TLUS), using a newly developed algorithm, and grading on postpartum examination. A secondary aim was to assess the correlation between tear severity, as defined on ultrasound, and symptoms of anal incontinence and/or fecal urgency.

METHODS

This was a retrospective study of patients seen at a perineal clinic between 2012 and 2018, after recent primary repair of OASI. All patients underwent a standardized interview including the St Mark's anal incontinence test and four-dimensional TLUS. Post-processing of ultrasound volume data was performed blinded to all other data. Using tomographic ultrasound imaging, a set of eight slices was obtained, and the central six slices were evaluated for sphincter abnormalities. Slices with distortion, thinning or defects were rated as abnormal. The following algorithm was used to grade OASI: a Grade-3a tear was diagnosed if the external anal sphincter (EAS) was abnormal in < 4/6 slices; a Grade-3b tear was diagnosed if the EAS was abnormal in ≥ 4/6 slices; and a Grade-3c/4 tear was diagnosed if both the EAS and internal anal sphincter were abnormal in ≥ 4/6 slices. Clinical grading of OASI was determined according to the Royal College of Obstetricians and Gynaecologists guidelines. Agreement between clinical and TLUS diagnosis of OASI was evaluated using weighted κ.

RESULTS

Of the 260 women seen during the study period, 45 (17%) were excluded owing to missing data or a repeat OASI, leaving 215 complete datasets for analysis. The average follow-up interval was 2.4 months (range, 1-11 months) after OASI and the mean age of the women was 29 years (range, 17-42 years). One hundred and seventy-five (81%) women were vaginally primiparous. OASI was graded clinically as Grade 3a in 87 women, Grade 3b in 80, Grade 3c in 29 and Grade 4 in 19. On imaging, full agreement between clinical and TLUS grading was noted in 107 (50%) women, with a weighted κ of 0.398. In 96 (45%) women, there was disagreement by one category, with a weighted κ of 0.74 and in 12 (6%) there was disagreement by two categories. Twenty-four (11%) women were found to have a normal anal sphincter on imaging. Overall, potential clinical over-diagnosis was noted in 72 (33%) women and potential under-diagnosis in 36 (17%). The seniority of the diagnosing obstetrician did not significantly alter agreement between clinical and sonographic OASI grading (κ 0.44, 0.43, and 0.34, for specialists and senior and junior residents, respectively). The association between symptoms of anal incontinence and/or fecal urgency and TLUS grading did not reach significance (P = 0.052).

CONCLUSIONS

Clinical and TLUS-based grading of OASI showed fair agreement. Clinical over-diagnosis may be increasingly common in our population, although under-diagnosis may still occur in a significant minority. Copyright © 2020 ISUOG. Published by John Wiley & Sons Ltd.

Outcome of anal symptoms and anorectal function following two obstetric anal sphincter injuries (OASIS)-a nested case-controlled study

Introduction and hypothesis

Obstetric anal sphincter injury (OASI) is a significant risk factor for developing anal incontinence. It can therefore be hypothesised that recurrent OASI in a subsequent delivery may predispose women to further anal sphincter dysfunction.

Methods

A nested case-controlled study based on data collected prospectively between 2006 and 2019. Women matched for age and ethnicity, with a history of one OASI and no sphincter damage in a subsequent delivery (control) were compared to women sustaining a second OASI. Assessment was carried out using the St Mark’s score (SMIS), anorectal manometry and endoanal ultrasound scan (findings quantified using the modified Starck score).

Results

Eighty-four women were included and equally distributed between the two groups, who were followed up 12 weeks postnatally. No difference in SMIS scores was found. Maximum resting pressure (MRP, mmHg) and maximum squeeze pressure (MSP, mmHg) were significantly reduced in the study group. Median (IQR) MRP in the study group was 40.0 (31.3–54.0) versus 46.0 (39.3–61.5) in the control group (p = 0.030). Median (IQR) MSP was 73.0 (58.3–93.5) in the study group versus 92.5 (70.5–110.8) (p = 0.006) in the control group. A significant difference (p = 0.002) was found in the modified Starck score between the study group (median 0.0 [IQR 0.0–6.0]) and control group (median 0.0 [IQR 0.0–0.0]).

Conclusions

We have demonstrated that women with recurrent OASI do not have significant anorectal symptoms compared to those with one OASI 12 weeks after delivery, but worse anal sphincter function and integrity. Therefore, on long-term follow-up, symptoms may possibly develop. This information will be useful when counselling women in a subsequent pregnancy.

Is endoanal, introital or transperineal ultrasound diagnosis of sphincter defects more strongly associated with anal incontinence?

INTRODUCTION AND HYPOTHESIS

Our aim was to explore the association between anal incontinence (AI) and persistent anal sphincter defects diagnosed with 3D endoanal (EAUS), introital (IUS) and transperineal ultrasound (TPUS) in women after obstetric anal sphincter injury (OASI) and study the association between sphincter defects and anal pressure.

METHODS

We carried out a cross-sectional study of 250 women with OASI recruited during the period 2013-2015. They were examined 6-12 weeks postpartum or in a subsequent pregnancy with 3D EAUS, IUS and TPUS and measurement of anal pressure. Prevalence of urgency/solid/liquid AI or flatal AI and anal pressure were compared in women with a defect and those with an intact sphincter (diagnosed off-line) using Chi-squared and Mann-Whitney U test.

RESULTS

At a mean of 23.6 (SD 30.1) months after OASI, more women with defect than those with intact sphincters on EAUS had AI; urgency/solid/liquid AI vs external defect: 36% vs 13% and flatal AI vs internal defect: 27% vs 13%, p < 0.05. On TPUS, more women with defect sphincters had flatal AI: 32% vs 13%, p = 0.03. No difference was found on IUS. Difference between defect and intact sphincters on EAUS, IUS and TPUS respectively was found for mean [SD] maximum anal resting pressure (48 [13] vs 55 [14] mmHg; 48 [12] vs 56 [13] mmHg; 50 [13] vs 54 [14] mmHg) and squeeze incremental pressure (33 [17] vs 49 [28] mmHg; 37 [23] vs 50 [28] mmHg; 36 [18] vs 50 [30] mmHg; p < 0.01).

CONCLUSIONS

Endoanal ultrasound had the strongest association with AI symptoms 2 years after OASI. Sphincter defects detected using all ultrasound methods were associated with lower anal pressure.

Comparison of transperineal and endoanal ultrasound in detecting residual obstetric anal sphincter injury

INTRODUCTION

Endoanal ultrasound is considered the gold standard when assessing the obstetric anal sphincter complex. Due to its relative intrusiveness and economic cost, other ultrasound modalities are on the rise, such as transperineal ultrasound with a convex probe. The aim of our study was to evaluate the agreement between endoanal ultrasound scores (EAUS score) and transperineal ultrasound scores (TPUS score) in assessing residual obstetric anal sphincter defects.

MATERIAL AND METHODS

Fifty-nine women were examined 6 months after primary suturing of obstetric anal sphincter injury with two ultrasound modalities. A standardized scoring system analyzing the length, depth and radial extent of both the external (EAS) and internal (IAS) sphincter was used. Wexner fecal incontinence score was used to assess the patients' symptoms.

RESULTS

Transperineal ultrasound scores score showed a strong significant correlation with EAUS score during both pelvic floor relaxation and contraction: Spearman's rho [r_s ] = 0.74, P < 0.001, and r_s  = 0.77, P < 0.001, respectively. For both EAS and IAS, significant correlations were found for all parameters, that is, length, depth and angle between both EAUS and TPUS. A statistically significant correlation was found between EAUS score and Wexner score (r_s  = 0.36, P = 0.005). A significant correlation between the EAS-EAUS score (r_s  = 0.36, P = 0.005) and Wexner score was found, but no significance was found between IAS-EAUS score and Wexner score (r_s  = 0.22, P = 0.097). Significant correlations were found for Wexner score and TPUS score in resting state (r_s  = 0.36, P = 0.01) and contracting state (r_s  = 0.28, P < 0.05), and between Wexner score and EAS-TPUS score in resting state (r_s  = 0.32, P = 0.02).

CONCLUSIONS

The results indicated a strong agreement between endoanal and transperineal ultrasound in assessing residual obstetric anal sphincter defects 6 months after primary suturing. Furthermore, a weak significant correlation was found between the ultrasound scores and the patients' Wexner fecal incontinence score.

Comparing the diagnostic accuracy of 3 ultrasound modalities for diagnosing obstetric anal sphincter injuries

BACKGROUND

The optimal imaging modality of obstetric anal sphincter injuries needs to take into consideration convenience, availability, and ability to assess the sphincter morphologic condition. Endoanal ultrasound imaging currently is regarded as the reference standard, but it is not widely available in obstetric units. Exoanal alternatives exist, such as 3-dimensional introital or transperineal ultrasound imaging, which are already readily available in most obstetrics and gynecology units.

OBJECTIVE

The primary objective was to evaluate the diagnostic accuracy of 3-dimensional introital and 3-dimensional transperineal ultrasound imaging compared with 3-dimensional endoanal ultrasound imaging as the reference standard for the detection of anal sphincter defects in women who sustained obstetric anal sphincter injuries. The secondary objective was to correlate a diagnosis of anal sphincter defect on imaging to symptoms of anal incontinence, and to assess patient discomfort that is experienced for each imaging modality.

STUDY DESIGN

A cross-sectional study was conducted of 250 women who sustained obstetric anal sphincter injuries, all of whom underwent 3-dimensional introital, transperineal, and endoanal ultrasound imaging. Introital and transperineal ultrasound imaging were assessed with tomographic ultrasound imaging. All of the women completed a validated modified St Mark's Score and Visual Analogue Score for discomfort. Optimal cut-off values for a significant defect on tomographic ultrasound imaging were defined as those with the greatest sensitivity and specificity based on receiver operating characteristic curves with endoanal ultrasound imaging as the reference standard. Diagnostic test characteristics of introital and transperineal ultrasound imaging were calculated with the use of these optimal cut-offs.

RESULTS

Optimal cut-off for a significant external anal sphincter defect was ≥3 of 7 slices; sensitivity and specificity were 0.65 and 0.75 on introital imaging and 0.70 and 0.69 on transperineal ultrasound imaging. Optimal cut-off for a significant internal anal sphincter defect was ≥2 of 5 slices; sensitivity and specificity were 0.59 and 0.84 on introital imaging and 0.43 and 0.97 on transperineal ultrasound imaging. The area under the curve for the diagnosis of external and internal anal sphincter defects ranged from 0.70-0.74 (P<.001) for introital and transperineal imaging. Positive predictive value for external and internal sphincter defects ranged from 0.37-0.63, and negative predictive value ranged from 0.85-0.93 for introital and transperineal ultrasound imaging. Endoanal ultrasound imaging was the only modality for a defect to correlate with symptoms; mean modified St. Mark's score for a defect sphincter was 2.4 (standard deviation, 4.1) and for an intact sphincter was 0.9 (standard deviation, 2.7; P<.01). Introital and transperineal ultrasound imaging were associated with less discomfort than endoanal ultrasound imaging.

CONCLUSION

Endoanal ultrasound imaging remains the most accurate diagnostic imaging modality. With low positive predictive values, introital and transperineal ultrasound imaging are not suitable for the identification of sphincter defects; however, high negative predictive values show a good ability to detect an intact sphincter. The optimal cut-off number of slices on tomographic ultrasound imaging for external and internal anal sphincters allows for standardization of a significant defect. In women with a history of obstetric anal sphincter injuries, introital and transperineal ultrasound imagings are suitable to screen for an intact sphincter if endoanal ultrasound imaging is not available. When defects are found, women should then have endoanal ultrasound imaging to verify the diagnosis.

The Role of Three-Dimensional Endoanal Ultrasound on Diagnosis and Classification of Sphincter Defects After Childbirth

BACKGROUND

Diagnostic tests for fecal incontinence have been improved over time. This study aims to evaluate the role of Three-dimensional endoanal ultrasound (3D-EUS) and the Starck's score in the assessment and treatment of obstetric sphincter injuries.

METHODS

A prospective observational study was performed including primiparous women who were evaluated at 20 wk of pregnancy and 3 mo after childbirth. Sphincter defects were classified according to the Starck's and Obstetrical Anal Sphincter Injuries classifications. Patients also completed the Fecal Incontinence Quality of Life and the Wexner questionnaires before and after childbirth.

RESULTS

Sphincter defects were detected in 45% of the 56 women included, although 85% had an uneventful delivery. Most defects were found isolated to the external anal sphincter except for two cases, classified by a Starck's score >8. Fecal Incontinence Quality of Life and Wexner questionnaires showed a rate of symptomatic patients of around 46%. We observed that 30% of patients with sphincter injuries remained asymptomatic.

CONCLUSIONS

The 3D-EUS is a useful test in assessing sphincter defects after childbirth. This method makes it possible to detect small sphincter defects that otherwise would have gone unnoticed, as 30% of patients with sphincter injuries were asymptomatic. In addition, both the 3D-EUS and the Starck's score were valuable in establishing an algorithm for the treatment of obstetric sphincter injuries.

How repeatable is assessment of external anal sphincter trauma by exoanal 4D ultrasound?

OBJECTIVE

Three-/four-dimensional translabial ultrasound (TLUS) is gaining popularity for the assessment of anal sphincter trauma, although repeatability data are lacking. This study aimed to determine the repeatability of tomographic ultrasound imaging (TUI) on TLUS for the diagnosis of external anal sphincter (EAS) trauma and compare the performance of a novice with that of an experienced investigator.

METHODS

This was a retrospective study of archived ultrasound datasets of patients who presented with symptoms of pelvic floor dysfunction and were examined twice between 2012 and 2016 at an average interval of 260 (range, 1-1100) days. All volumes were obtained using a GE Medical Systems Voluson 730 Expert or E8 ultrasound system. Post-processing of volumes was performed independently by two investigators, one with over 1 year's experience and another with no prior experience in using TUI, who were blinded to clinical data, each other's results and the results obtained at the first timepoint. Significant trauma on EAS was diagnosed if four of the six TUI slices showed a defect of ≥ 30°. Intra- and interobserver agreement were determined using Cohen's kappa (κ) and intraclass correlation coefficients.

RESULTS

During the study period, 105 women underwent two TLUS assessments of the anal sphincter. Of these, 103 patients with ultrasound volumes available for both timepoints were included in the analysis. The novice investigator demonstrated average repeatability for assessment of significant EAS trauma and single-slice defect (κ, 0.30 and 0.22, respectively) despite relatively high agreement between measurements obtained at the two timepoints (84.5% and 79.3%, respectively). The experienced investigator demonstrated good to very good repeatability for significant EAS trauma and single-slice defect (κ, 0.91 and 0.78, respectively) between the two assessments, which equates to 98.1% and 94.7% agreement, respectively.

CONCLUSION

The repeatability of TLUS measurements for diagnosis of EAS trauma seems to be very good when imaging is undertaken with state-of-the-art equipment and the analysis is performed by an experienced observer; however, the performance of a novice investigator is much poorer. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Medium- to Long-term Follow-up of Obstetric Anal Sphincter Injury

BACKGROUND

Obstetric anal sphincter injury is the primary modifiable risk factor for anal incontinence in women. Currently, endoanal ultrasound is most commonly used to detect residual anal sphincter defects after childbirth. Translabial ultrasound has recently been introduced as a noninvasive alternative.

OBJECTIVES

This study aimed to determine medium- to long-term outcomes in women after obstetric anal sphincter injuries diagnosed and repaired at delivery.

DESIGN

This is a cross-sectional study.

SETTINGS

This study was performed in a tertiary obstetric unit.

PATIENTS

Between 2005 and 2015, 707 women were diagnosed with obstetric anal sphincter injuries; 146 followed an invitation for follow-up.

INTERVENTIONS

Clinical examination, anal manometry, and translabial ultrasound were performed.

MAIN OUTCOME MEASURES

The primary outcomes measured were the St Mark incontinence score and the evidence of sphincter disruption on translabial ultrasound.

RESULTS

Of 372 contactable patients, 146 attended at a mean follow-up of 6.6 years (1.7-11.9), of which 75 (51%) reported symptoms of anal incontinence with a median "bother score" of 6 (interquartile range, 3-8). Median St Mark score was 3 (interquartile range, 2-5). Twenty-four (16%) had a score of ≥5. Women who had been diagnosed with a 3c/4th degree tear had more symptoms (58% vs 44%), significantly lower mean maximal resting pressure (p < 0.001), maximal squeeze pressure (p < 0.001), and more residual external (p < 0.001) and internal (p = 0.012) sphincter defects in comparison with those who had a 3a/3b tear. Women with residual external sphincter defects had lower mean maximal squeeze pressure (p = 0.02). Residual internal sphincter defects (p = 0.001) and levator avulsion (p = 0.048) are independent risk factors for anal incontinence on multivariate modeling.

LIMITATIONS

This study was limited by the lack of predelivery data of bowel symptoms and BMI and incomplete intrapartum documentation of tear grade.

CONCLUSIONS

Symptoms of anal incontinence were highly prevalent (51%), with a high bother score of 6. St Mark scores were associated with residual internal anal sphincter defects and levator avulsion. Women who had a higher tear grade showed a higher incidence of residual sphincter defects and lower manometry pressures. See Video Abstract at http://links.lww.com/DCR/A824.

Exoanal Imaging of the Anal Sphincters

Since its introduction in the early 1990s, endoanal sonography has become the mainstay of morphologic assessment of the anal canal and sphincter, especially for obstetric anal sphincter trauma. Lack of availability of suitable systems and the invasive nature of the method have limited uptake and clinical utility. More recently, exoanal or transperineal/translabial tomographic imaging has been developed as a noninvasive alternative. This pictorial overview aims to introduce the reader to this new diagnostic modality and to demonstrate common findings in asymptomatic and symptomatic women.

Sacral neuromodulation for combined faecal and urinary incontinence following obstetric anal sphincter injury

AIM

The aim of this study was to investigate the efficacy of sacral neuromodulation (SNM) in the treatment of faecal incontinence and concomitant urinary incontinence in women with a history of obstetric anal sphincter injury (OASIS).

METHOD

In this prospective study, consecutive women with faecal incontinence following OASIS accepted for SNM were screened for concomitant urinary incontinence. The primary outcome was the change in urinary incontinence score on the International Consultation on Incontinence Questionnaire for Urinary Incontinence, Short Form (ICIQ-UI-SF), between baseline and 12 months. Secondary outcomes included the change in St Mark's score, sexual function and quality of life, change in grade of urinary incontinence and disappearance of urgency.

RESULTS

From March 2012 to September 2014, 39 women with combined faecal incontinence and urinary incontinence received SNM. Thirty-seven women were available for analysis after 12 months. The mean reduction in the ICIQ-UI-SF score between the baseline and 12 months was 5.8 (95% CI 3.7-8.0, P < 0.001). ICIQ-UI-SF was reduced in 29 (78%) women, urinary incontinence resolved in 13/37 (35%, 95% CI 20%-50%) patients, and urgency disappeared in 14/33 (42%, 95% CI 26%-59%). The mean reduction in the St Mark's score was 10.6 (95% CI 8.6-12.7, P < 0.001). Disease-specific quality of life, Euroqual 5-dimension visual analogue scale (EQ-5D VAS) and several areas of sexual function changed significantly for the better.

CONCLUSION

More than three-quarters of the women with combined faecal and urinary incontinence following OASIS reported a successful outcome with reduction in ICIQ-UI-SF at 12 months after SNM.

Overdiagnosis and rising rate of obstetric anal sphincter injuries (OASIS): time for reappraisal

OBJECTIVES

To determine the accuracy of clinical diagnosis of obstetric anal sphincter injuries (OASIS) using three-dimensional (3D) endoanal ultrasound (EA-US) and to compare symptoms and anal manometry measurements between women with anal sphincters adequately repaired and those with persistent anal sphincter defects.

METHODS

The EA-US images of women with clinically diagnosed and repaired OASIS, defined as third- or fourth-degree perineal tear, who attended the perineal clinic at Croydon University Hospital over a 10-year period (2003-2013) were reanalyzed by a single expert blind to symptoms and the results of clinical examination. St Mark's Incontinence Scores (SMIS) and anal manometry measurements were obtained and compared between women with an intact anal sphincter and those with an anal sphincter scar and between those with an intact anal sphincter and those with a defect. Anal manometry measurements were compared between women with an external anal sphincter (EAS) defect and those with an internal anal sphincter (IAS) defect.

RESULTS

The images of 908 women were reanalyzed. No evidence of OASIS was found in 64 (7.0%) women, an EAS scar alone was detected in 520 (57.3%) and an anal sphincter defect in 324 (35.7%). Of the 324 women with a defect, 112 had an EAS defect, 90 had an IAS defect and 122 had a combined IAS and EAS defect. SMIS results were significantly higher in women with an anal sphincter defect compared with those with no evidence of OASIS (P = 0.018), but there was no significant difference in scores between women with an intact sphincter and those with an EAS scar only. Women with a defect had a significantly lower maximum resting pressure (median (range), 44 (8-106) vs 55 (29-86) mmHg; P < 0.001) and maximum squeeze pressure (median (range), 74 (23-180) vs 103 (44-185) mmHg; P < 0.001) compared with those in the intact group. Similar, but less marked, differences were observed in women with an EAS scar compared with those who had an intact anal sphincter. The anal length was significantly shorter in women with a defect compared with those in the intact group (median (range), 20 (10-40) vs 25 (10-40) mm; P = 0.003).

CONCLUSIONS

Seven percent of women with a clinical diagnosis of OASIS were wrongly diagnosed. We believe that this rate may differ from that of other units but training methods and competency assessment tools for the diagnosis and repair of OASIS need urgent reappraisal. The role of EA-US in the immediate postpartum period needs further evaluation as the accurate interpretation of the images is dependent on the expertise of the staff involved. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

Sacral neuromodulation compared with injection of bulking agents for faecal incontinence following obstetric anal sphincter injury - a randomized controlled trial

AIM

The purpose of this trial was to compare the effectiveness of sacral neuromodulation (SNM) with a submucosal injection of collagen (Permacol®) in women with faecal incontinence following obstetric anal sphincter injury (OASIS).

METHOD

This single-blinded randomized controlled trial at two hospital units in Norway included women with faecal incontinence following OASIS. Eligible women who had had a successful percutaneous nerve evaluation were randomly assigned to SNM or Permacol®. The primary outcome was the difference in the St Mark's incontinence score between baseline and 6 months. Secondary outcomes were changes in the disease-specific quality of life (FIQL) and urinary incontinence (ICIQ-UI-SF) scores.

RESULTS

Fifty-eight women were randomly assigned to SNM (n = 30) and Permacol® (n = 28). The reduction in the St Mark's score between baseline and 6 months was 11.2 (SD 5.3) in the SNM group vs 2.3 (SD 5.0) in the Permacol® group, resulting in a difference of 8.9 (95% CI: 6.1-11.7, P < 0.0001). The differences in the four scales of FIQL (lifestyle, coping, depression, embarrassment) were 0.90 (95% CI: 0.50-1.30, P < 0.001), 1.05 (0.62-1.47, P < 0.001), 0.52 (95% CI: 0.16-0.87, P = 0.005) and 0.95 (95% CI: 0.50-1.40, P < 0.001), respectively, in favour of SNM. The difference in the ICIQ-UI-SF was 5.0 (95% CI: 1.97-8.02, P = 0.002) in favour of SNM. There were nine minor adverse events in the SNM group compared with seven in the Permacol® group (P = 0.77).

CONCLUSION

SNM was superior to Permacol® in terms of reduction of St Mark's score, ICIQ-UI-SF and the change of the FIQL in women with faecal incontinence following OASIS.

Sacral neuromodulation for faecal incontinence following obstetric sphincter injury - outcome of percutaneous nerve evaluation

AIM

The purpose of this study was to assess the efficacy of percutaneous nerve evaluation (PNE) in women with faecal incontinence (FI) following obstetric anal sphincter injury and to relate the outcomes to baseline factors, with special emphasis on the extent of the sphincter defect.

METHOD

This was a prospective study at a tertiary colorectal referral unit at the University Hospital of North Norway conducted from 2012 to 2014. Sixty-three women underwent a 3-week PNE using a tined lead and the Verify^® external neurostimulator. The primary outcome was efficacy, defined as the percentage reduction in weekly FI episodes, and patients with a reduction of 50% or more were defined as responders. Baseline factors affecting the primary outcome were explored. Sphincter defects were classified with a validated three-dimensional endoanal ultrasound defect score.

RESULTS

Fifty-six (89%) of the 63 women were responders with a reduction in weekly FI episodes of 94.5%, from a median (interquartile range) of 4.8 (2.0-11.0) to 0.5 (0-2.0) (P < 0.001). Twenty-nine (52%) reported no weekly FI episodes, and urgency episodes disappeared in 18 (32%). In the multivariable linear regression model, efficacy was related to concomitant urinary incontinence (P = 0.04), body mass index (BMI) (P = 0.03) and pain during PNE (P = 0.046) but not to the extent of the sphincter defect (P = 0.1). Responders had a higher St Mark's score than nonresponders (P = 0.046).

CONCLUSIONS

The vast majority of women had successful PNE tests. Responders had higher baseline St Mark's scores than nonresponders. Efficacy was related to concomitant urinary incontinence, BMI and pain, not to the extent of the sphincter defect.

Is obstetric anal sphincter injury a risk factor for levator ani muscle avulsion in vaginal delivery?

OBJECTIVE

To analyze whether women who sustain obstetric anal sphincter injury (OASI) in their first vaginal delivery have a higher incidence of levator ani muscle (LAM) avulsion than do women without OASI.

METHODS

We conducted a prospective observational cohort study of 80 primiparous women who gave birth at our tertiary obstetric unit between September 2011 and July 2013. The women were divided into two groups: women diagnosed with OASI during vaginal delivery (n = 40) and women without OASI (n = 40), matched by mode of delivery and newborn birth weight. Four-dimensional (4D) transperineal ultrasound was performed in all participants at 6-12 months after delivery to assess for integrity or avulsion of the LAM. Ultrasound images were evaluated by two observers who were blinded to group assignment and clinical data. Interobserver agreement was assessed to determine the reproducibility of 4D transperineal ultrasound for diagnosing LAM avulsion.

RESULTS

We found no statistically significant differences between the two groups. The incidence of LAM avulsion was 24.3% in the OASI group and 34.2% in the control group (P = 0.448). Interobserver agreement in the diagnosis of LAM avulsion in the study population using 4D transperineal ultrasound was 89.5%, with a kappa index of 0.76.

CONCLUSIONS

Our findings do not support OASI as a risk factor for LAM avulsion. Prospective studies in larger populations are needed to establish the biomechanical relationships of the pelvic floor structures involved in vaginal delivery. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.

Obstetric anal sphincter injury: a follow-up questionnaire study on longer-term outcomes

INTRODUCTION AND HYPOTHESIS

Obstetric anal sphincter injuries (OASIS) contribute significantly to the development of anal incontinence (AI) in women. The aim of this study was to establish the incidence of AI after OASIS and to study the influence on the quality of life (QoL) in patients with OASIS.

METHODS

This cohort study, with prospective case-control follow-up, involves women who were treated for OASIS between 2005 and 2012 in two academic medical centers in The Netherlands. Three hundred and thirteen patients and 780 controls were invited to complete a validated questionnaire (Defecation Distress Inventory, Wexner Incontinence Score, and Fecal Instrument Quality of Life) regarding symptoms and bother of AI subsequent and QoL after delivery. The main outcome measures were the presence of AI and the impact on QoL.

RESULTS

The questionnaire was completed by 141 patients and 194 controls. Mean follow-up was 4 years (range 1-9 years) in both groups. In the patient group, 55 women (39 %) reported AI symptoms compared with 38 women (20 %) in the control group (odds ratio 2.7, 95 % confidence interval 1.66-4.47, p < 0.01). In women who experienced symptoms of AI as very bothersome, QoL was affected in 14 (82.0 %) patients and three (33.5 %) controls (p = 0.012).

CONCLUSIONS

In this study, women with OASIS had a more than doubled risk of longer-term bothersome symptoms of AI compared with controls. Symptoms were experienced as bothersome and as having an influence on QoL.

[Applicability of 3/4D transperineal ultrasound for the diagnosis of anal sphincter injury during the immediate pospartum]

BACKGROUND

The most common cause of anal sphincter injuries in women is vaginal birth. Endo-anal ultrasound is currently used for the diagnosis of anal sphincter defect. However, due to the inconvenience caused, it is not an applicable technique during the immediate post-partum. The aim of this study was to determine whether transperineal ultrasound in 3/4D is a useful diagnostic method for the assessment of anal sphincter during the immediate post-partum.

MATERIAL AND METHODS

A prospective study was conducted on the vaginal deliveries performed between September 2012 and June 2013 in the Valme University Hospital (Seville). Obstetric and foetal parameters that could influence the onset of perineal tears were studied. The patients underwent a transperineal 3/4D ultrasound and a multislice study (48hours after birth).

RESULTS

The study included 146 puerperal women. The sphincter complex was assessed in all of them during the immediate post-partum. External anal injuries were observed in 10.3% of the cases. In 8.2% of cases, the primary suture of the external anal sphincter was detected during ultrasound examination, and 2.1% of asymptomatic lesions were diagnosed only with post-partum ultrasound. None of the patients reported discomfort or pain.

CONCLUSIONS

The 3-dimensional transperineal ultrasound is helpful in determining the primary repair of the anal sphincter during the immediate post-partum, with no discomfort for patients, as well as for establishing those early sphincter injuries that go unnoticed during vaginal delivery.

The relationship of 3-D translabial ultrasound anal sphincter complex measurements to postpartum anal and fecal incontinence

INTRODUCTION AND HYPOTHESIS

We aimed to determine whether anal sphincter complex (ASC) measurements on translabial ultrasound (TL-US) were related to anal incontinence (AI) or fecal incontinence (FI) symptoms 6 months postpartum.

METHODS

A prospective cohort of primiparous women underwent TL-US 6 months after a vaginal birth (VB) or cesarean delivery (CD). Muscle thickness was measured at 3, 6, 9, and 12 o'clock positions of the external anal sphincter (EAS), the same four quadrants of the internal anal sphincter (IAS) at proximal, mid, and distal levels, and at the bilateral pubovisceralis muscle (PVM). Measurements were correlated to AI and FI on the Wexner Fecal Incontinence Scale, with sub-analyses by mode of delivery. The odds ratio (OR) of symptoms was calculated for every 1 mm increase in muscle thickness (E1MIT).

RESULTS

A total of 423 women (299 VB, 124 CD) had TL-US 6 months postpartum. Decreased AI risk was associated with thicker measurements at the 6 o'clock (OR 0.74 E1MIT) and 9 o'clock proximal IAS (OR 0.71 E1MIT) in the entire cohort. For CD women, thicker measurements of the 9 o'clock proximal IAS were associated with decreased risk of AI (OR 0.56 E1MIT) and thicker distal 6 o'clock IAS measurements were related to a decreased risk of FI (OR 0.37 E1MIT). For VB women, no sphincter measurements were significantly related to symptoms, but thicker PVM measurements were associated with increased risk of AI (right side OR 1.32 E1MIT; left side OR 1.21 E1MIT).

CONCLUSIONS

ASC anatomy is associated with AI and FI in certain locations; these locations vary based on the patient's mode of delivery.

Residual defects of the external anal sphincter following primary repair: an observational study using transperineal ultrasound

OBJECTIVES

Obstetric anal sphincter tears are common and an important factor in the etiology of anal incontinence. The objective of the study was to evaluate the prevalence of residual defects of the external anal sphincter (EAS) after primary repair of obstetric anal sphincter injury using four-dimensional (4D) transperineal ultrasound and to correlate sonographic findings of residual defects and levator avulsion with significant symptoms of anal incontinence, defined as St Mark's fecal incontinence score (SMIS) of ≥ 5.

METHODS

This was a retrospective observational study. One-hundred and forty women were seen after primary repair of obstetric anal sphincter tears in a dedicated perineal clinic at a tertiary hospital in Australia. They all underwent a standardized interview, and physical and 4D transperineal ultrasound examination.

RESULTS

Mean follow-up interval was 1.9 months after delivery. Eighty-nine (64%) women had a 3a/3b tear, 28 (20%) a 3c/4(th) degree tear and 23 (16%) an unclassified 3(rd) degree tear. Thirty-five (25%) patients reported symptoms of anal incontinence. Nine had an SMIS of ≥ 5. A residual defect was found in 56 (40%) cases and levator avulsion in 27 (19%). On multivariate logistic regression, residual defects (P = 0.03; odds ratio (OR) = 6.38; 95% CI, 1.23-33.0) and levator avulsion (P = 0.047; OR = 4.38; 95% CI, 1.02-18.77) were found to be independent risk factors for anal incontinence.

CONCLUSIONS

Residual defects of the EAS were found on transperineal ultrasound in 40% of women after primary repair of obstetric anal sphincter injuries. Although most were asymptomatic, residual anal sphincter defects and levator avulsion were associated with significant symptoms of anal incontinence as quantified using the SMIS.

Long-term function and morphology of the anal sphincters and the pelvic floor after primary repair of obstetric anal sphincter injury

AIM

More than 50% of women experience deteriorating continence over time following primary repair of obstetric anal sphincter injuries. The objectives of this study were to assess the function and morphology of the anal sphincters and pelvic floor in women with long-term faecal incontinence after sphincter repair (primary end-point) and to evaluate their correlation with severity of incontinence (secondary end-point).

METHOD

The participants in this prospective study were recruited from a cohort of all women who sustained third or fourth degree obstetric sphincter injury reconstruction (cases) from January 1976 to November 1991. The women who delivered immediately before and after each case, without sustaining obstetric damage, were included as controls. Cases and controls were stratified into three categories: (i) continent; (ii) minor incontinence; and (iii) severe incontinence. The function and morphology of the anal sphincters and pelvic floor were evaluated by MRI, three-dimensional endoanal ultrasonography and anorectal physiology tests.

RESULTS

Fifty-nine women (29 cases/30 controls; mean age 51/53 years; mean follow-up 23.7/24.1 years, respectively) were assessed. Morphologically, cases had a significantly shorter anterior external anal sphincter length compared with controls when evaluated by three-dimensional endoanal ultrasonography (8.6 vs 10.2 mm; P = 0.03). Functionally, cases with severe incontinence had a significantly shorter anterior sphincter length compared with cases with minor incontinence (7.7 vs 10.4 mm; P = 0.04). No correlation could be found between anal pressures and severity of incontinence in the case group.

CONCLUSIONS

Cases had a significantly shorter anterior external anal sphincter length. Functionally, anterior sphincter length correlated with increased severity of incontinence.

Incontinence after primary repair of obstetric anal sphincter tears is related to relative length of reconstructed external sphincter: a case-control study

OBJECTIVE

To determine if anatomic primary repair with end-to-end reconstruction of the external anal sphincter (EAS) in its full length combined with separate repair of coexisting internal anal sphincter (IAS) tear, when present, results in less incontinence and better anal sphincter integrity compared with conventional primary end-to-end repair in which the IAS is not actively reconstructed.

METHODS

Women who sustained third- or fourth-degree obstetric tears were included prospectively in the study following anatomic primary repair. Women treated with conventional primary repair prior to the study period comprised the control group. Three-dimensional endoanal ultrasonography (3D-EAUS) images were classified according to the EAUS defect score, and incontinence according to St Mark's score.

RESULTS

Sixty-three women were included in the study group and 61 in the control group, with mean follow-up times of 11 and 21 months, respectively. Among women who had not delivered vaginally prior to the tear, St Mark's score ≥ 3 was reported by 9.6% (5/52) in the study group and 37.5% (15/40) in the control group at follow-up (P = 0.002). The corresponding numbers among women who had previously delivered vaginally were 36.4% (4/11) and 42.9% (9/21), respectively (non-significant). St Mark's score correlated with the EAUS defect score (P = 0.017). An EAS defect exceeding 50% of the sphincter length was significantly less common in the study group, and in a multivariable logistic regression model, mode of repair (anatomic vs conventional) was the only factor explaining the difference in EAS sphincter length between the two groups (P = 0.007).

CONCLUSION

Improved continence status after anatomic primary repair was associated with a better longitudinal reconstruction of the EAS, while the integrity of the IAS did not differ between the groups. Women with a history of vaginal delivery prior to the sphincter tear had an inferior outcome regardless of mode of repair.

Development of the maternal anal canal during pregnancy and the postpartum period: a longitudinal and functional ultrasound study

OBJECTIVES

Normal anatomical and physiological development of the maternal anal canal during and after pregnancy has been documented scarcely. We aimed to study the position and volume of the anal canal, during and after pregnancy, in women without previous delivery.

METHODS

This was a longitudinal study in which transvaginal three-dimensional ultrasound was used to measure anatomical structures in the anal canal during rest and squeeze in 23 nulliparous women. The total anal canal volume (ACV), anorectal curvature (ARC), anovaginal angle (AVA) and anal canal length were determined at 18, 28 and 36 weeks of pregnancy and at 3 months postpartum.

RESULTS

Total ACV at rest increased from a mean of 10.17 cm(3) at 18 weeks to 12.37 cm(3) and 12.21 cm(3) at 28 and 36 weeks, respectively (P = 0.001 and P = 0.010 vs. first measurement). For anal canal length, the corresponding mean measurements were 3.91 cm, 4.07 cm (P = 0.13) and 4.21 cm (P = 0.017). Postpartum, the mean total ACV was 10.86 cm(3) and length was 3.90 cm (P = 0.10 and P = 0.70 vs. first measurement). No significant changes were observed in ARC and AVA during or after pregnancy. Compared to at-rest status, the anal length significantly increased on voluntary squeeze (P = 0.007, 0.007, 0.022 and 0.004 at the four time points), while no differences in total ACV were observed. In mid-pregnancy AVA significantly increased during squeeze (P = 0.006 and 0.002 at weeks 18 and 28, respectively).

CONCLUSION

Anal canal length and total ACV increase during pregnancy in women without previous delivery. Voluntary squeezing elongates the anal canal and increases the angle formed with respect to the direction of the vagina. During postpartum involution, the characteristics of the anal canal revert to those observed at 18 weeks of pregnancy.

Detection of anal sphincter defects in female patients with fecal incontinence: a comparison of 3-dimensional transperineal ultrasound and 2-dimensional endoanal ultrasound

BACKGROUND

Endoanal ultrasound is widely used for the detection of external and internal anal sphincter defects in patients with fecal incontinence. Recently, 3-dimensional transperineal ultrasound has been introduced as a noninvasive imaging method for the detection of these sphincter defects.

OBJECTIVE

This study was designed to assess agreement between 3-dimensional transperineal ultrasound and 2-dimensional endoanal ultrasound regarding the detection of anal sphincter defects in women with fecal incontinence.

DESIGN

This study was designed as a prospective observational study.

SETTINGS

The study took place in a university hospital.

PATIENTS

Between October 2008 and June 2009, all women with concerns of fecal incontinence underwent 2-dimensional endoanal ultrasound as well as 3-dimensional transperineal ultrasound.

MAIN OUTCOME MEASURES

The main outcome measures are the presence of external and internal anal sphincter defects.

RESULTS

Fifty-five patients were included. External and internal anal sphincter defects were observed with 2-dimensional endoanal ultrasound in 27 (49%) and 15 (27%) patients. Three-dimensional transperineal ultrasound detected an external and internal sphincter defect in 19 (35%) and 16 (29%) patients. The Cohen κ coefficient for the detection of external (κ = 0.63) and internal (κ = 0.78) anal sphincter defects was good.

LIMITATIONS

This study's limitations include the absence of a surgical examination as the reference standard in the determination of sphincter defects.

CONCLUSION

This study shows good agreement between 3-dimensional transperineal ultrasound and 2-dimensional endoanal ultrasound regarding the detection of anal sphincter defects. Based on these data, 3-dimensional transperineal ultrasound might be considered as a valuable alternative noninvasive investigation method.

Three-dimensional endoanal ultrasound and anorectal manometry in children with anorectal malformations: new discoveries

BACKGROUND/PURPOSE

Fecal incontinence and constipation are common problems in follow-up of anorectal malformations (ARMs). We evaluated the anal sphincters using the 3-dimensional endoanal ultrasonography (3D-EAUS) and the anorectal manometry after ARMs repair.

METHODS

Seventeen patients, divided into 3 groups according to Wingspread classification, underwent anorectal manometry and 3D-EAUS. Clinical, manometric, and endosonographic scoring systems were used.

RESULTS

The average anal resting pressure (aARP) was significantly higher in low ARMs than in intermediate and high ARMs. The anal squeeze pressure was not statistically different between the 3 groups. Three-dimensional EAUS visualized internal anal sphincter (IAS) disruptions in 7 of 17 patients and absence of IAS in 6 of 17 children with high ARMs. Scars of the external anal sphincter were localized in low ARMs and generalized in the other groups. In the case of IAS disruption with aARP greater than 20 mm Hg, fecal incontinence and constipation improved with biofeedback and/or laxatives, whereas daily enemas were necessary in absence of IAS with aARP less than 20 mm Hg. Statistical correlation was observed between endosonographic and manometric findings and clinical outcomes.

CONCLUSIONS

Lesions of the anal sphincter are common in ARMs. Three-dimensional EAUS and anorectal manometry ensure a complete assessment of the anal sphincter and could provide useful information to define the most appropriate treatments to improve the quality of life.