Assessment of sonographic quality of anal sphincter muscles in patients with faecal incontinence

Objective  The main application of endoanal ultrasonography (US) in evaluation of faecal incontinence is to identify surgically correctable sphincter defects. The aim of our study was to determine whether qualitative changes in echogenicity and in uniformity of internal (IAS) and external (EAS) anal sphincter muscles detected on endoanal US correlate with other anal laboratory tests and modified Wexner faecal incontinence functional score.
Method  Records on 99 patients having complete information on anorectal manometry, faecal incontinence scoring and available endoanal US imaging of the anal sphincters were included in statistical analysis. Anatomic appearance and changes in echogenicity of the anal sphincter muscles were recorded according to the proposed scoring system. Endoanal US defect and quality component scores for IAS and EAS as well as the total score were correlated with anal laboratory tests and incontinence score using Spearman's correlations test.
Results  There was a trend for correlation between IAS quality score and incontinence score ( P  = 0.06), but no correlation for IAS defect score. EAS defect score had a significant negative correlation with maximum squeeze pressure (MSP) ( P  = 0.031). Distal EAS quality score had a significant correlation with incontinence score ( P  = 0.002). EAS total score correlated with MSP ( P  = 0.02) and incontinence score ( P  = 0.006). Endoanal US total score was significantly correlated with incontinence score ( P  = 0.006), maximal resting (MRP) ( P  = 0.035) and MSP ( P  = 0.045) and high pressure anal canal zone length ( P  = 0.03).
Conclusion  Sonographic morphology of anal sphincter muscles correlates with anal laboratory tests and functional incontinence score. Qualitative ultrasound scoring instrument may improve evaluation of patients with faecal incontinence.     

Prospective study of the diagnostic evaluation of faecal incontinence and leakage in male patients

OBJECTIVE: Male faecal incontinence (FI) has received little attention. No consistent pathophysiological abnormality has been identified in those studies that have specifically assessed male patients with FI or faecal leakage (FL). This study was designed to re-examine the different theories relating to the pathophysiology of male incontinence and to assess if manometric and ultrasound assessment yields clinically relevant information that directs patient care. METHOD: This was a prospective study of all men referred to a Coloproctology clinic with incontinence. The Wexner Incontinence score was used to assess severity of symptoms. Specific investigations included anal manometry, rectal sensation and endo-anal ultrasound (EAUS). Results were compared with a group of 20 normal male controls. RESULTS: A total of 59 symptomatic male patients were investigated (36 FI, 23 FL). FL and control groups had similar maximum resting (MRP) and maximum squeeze pressure (MSP). The incontinence group had a significantly lower MRP & MSP compared with controls [MRP: FI 58 (42-75.5) vs control 85 (72-104)] (P < 0.0001), [MSP: FI 167 (125-215) vs control 248 (192-302)] (P < 0.0001). There was no significant difference in rectal sensation between the groups and the defecation index was also similar. EAUS detected only one external anal sphincter defect amongst the 23 male patients with FL. One external sphincter defect and three internal sphincter defects were identified amongst the 36 patients with incontinence. Of these five patients with sphincter defects, four had previously undergone anorectal surgery. [Results expressed as median (interquartile range): manometry expressed as mmHg]. CONCLUSION: Male patients presenting with faecal incontinence frequently show impaired sphincter function which may be associated with sphincter defects. In contrast, those presenting predominantly with FL have no morphological or physiological changes that might account for their symptoms. Investigating such patients with anorectal physiology and EAUS is usually unhelpful and can be omitted.     

Perineum compression during EAUS enhances visualization of anterior anal sphincter defects

Objective  Endo-anal ultrasound (EAUS) can detect anal sphincter injuries. However, anterior external anal sphincter (EAS) defects can be difficult to define. We assessed different EAUS techniques to determine if any particular method improved defect identification.
Method  Ninety females with faecal incontinence were prospectively studied. Wexner faecal incontinence scores were obtained. All patients underwent anorectal manometry and EAUS using three different techniques: standard, digit-assisted (gloved finger pressing on posterior vaginal wall) and balloon-assisted (standard balloon inflated into the vagina). The three techniques were assessed by comparing defect characteristics (detection, angle, edges and scar tissue), and perineal body thickness. All measurements were performed at the mid anal canal level. Results are expressed as medians (IQR).
Results  Standard EAUS (S-EAUS) identified a sphincter defect in 54 patients. Digit assisted EAUS (D-EAUS) and balloon-assisted EAUS (B-EAUS) ultrasound revealed a sphincter defect in additional 11 and 9 patients respectively compared to S-EAUS. Correlation of maximum squeeze pressure with EAUS findings improved on D-EAUS and B-EAUS. The defect angle was significantly wider with D-EAUS and B-EAUS [S-EAUS 90°(63–97), D-EAUS 100°(81–101.5), B-EAUS 100°(80–105), P  = 0.0005]. The perineal body was significantly thicker when measured with B-EAUS [D-EAUS 9 mm (7–10) vs B-EAUS 10 mm (8–11), P  = 0.0005]. Inter-observer agreement was comparable [S-EAUS (K) = 0.677, D-EAUS (K) = 0.658, B-EAUS (K) = 0.601].
Conclusion  EAS anterior defect detection and definition on EAUS may be improved by the demarcation and gentle pressure on the posterior vaginal wall.     

Three‐dimensional endoanal ultrasonography of external anal sphincter defects in patients with faecal incontinence: correlation with symptoms and manometry

Aim Anal sphincter anatomy on two‐dimensional endoanal ‐ultrasonography (EUS) does not always correlate with the clinical data. The purpose of this study was to determine whether three‐dimensional (3D) measurements yield a better correlation. Method The study group included consecutive patients who underwent 3D EUS for faecal incontinence over a 2‐year period. The medical charts were reviewed for Cleveland Clinic Foundation Fecal Incontinence (CCF‐FI) score and manometric pressures. Endoanal ultrasonographic images were reviewed for the presence of an external anal sphincter (EAS) defect and its extent, as determined by the radial angle, length in the sagittal plane and percentage volume deficit. Correlational analyses were performed between the clinical and imaging data. Results Sixty‐one patients of median age 53 years (range 15–82) were evaluated. Thirty‐two patients had either a complete (17) or partial (15) EAS defect, and 29 patients had an intact sphincter. The CCF‐FI scores were similar in patients with and without an EAS defect (12.5 ± 5.6 and 11.4 ± 5.5, respectively). The intact‐sphincter group had a significantly greater EAS length (3 ± 0.4 vs 2 ± 0.62 cm, P = 0.02) and higher mean maximal squeeze pressure (MMSP; 99.7 ± 52.6 vs 66.9 ± 52.9 mmHg, P = 0.009). There were no statistically significant correlations between MMSP, CCF‐FI score and EAS status on 3D EUS. Mean percentage volume of the defect was similar in patients with complete and partial tears (14.5 ± 5.5 and 17.5 ± 7.2%, P = 0.25) and showed no correlation with physiological tests or symptom scores. Conclusion Improvements in external anal sphincter imaging have not yielded a better association with the clinical findings. The lack of clinical differences between patients with different EAS tears may reflect their similar volumetric defects.     

Colorectal 25

Aims: To assess anal sphincter structure and functional outcomes following third-degree perineal tears and the effect of its disruption on the development of anal incontinence. Methods: Fifty-one consecutive patients, 41 primigravidae and 10 multigravidae, with third-degree intrapartum perineal tears, primarily repaired, were recruited 4 months postpartum. Patients completed questionnaires assessing faecal incontinence. Anal manometry and endosonography were then performed. Results: No patient reported incontinence prior to pregnancy. The incidence of faecal incontinence was 12 per cent. Six patients were incontinent of faeces and 10 incontinent of either flatus and/or fluid. Eighty-one per cent of anal incontinent patients were primigravidae (OR 0.96). Three women had previous third-degree tears, with one anal incontinence on subsequent delivery. Disruption of the external anal sphincter (EAS) was identified endosonographically in 26 patients. In 13 patients, there was an associated internal anal sphincter (IAS) defect. Clinically unsuspected tears of the Anal sphincter mechanism were diagnosed by anal endosonography in 46 per cent of asymptomatic patients. The EAS alone was involved in 14, IAS in three, and both in five patients. Clinical examination of women with anal incontinence identified an anal sphincter defect in 46 per cent. Ultrasound in anal incontinent patients showed an IAS defect in 42 per cent and an EAS defect in 52 per cent. All patients with faecal incontinence had a disruption of the EAS identified by endosonography (P < 0.05). No significant relationship was demonstrated between symptoms and anal manometry (P = 1.0, n.s.). Conclusions: Third-degree tears cause significant, although clinically unsuspected anal sphincter defects. It may be that anal manometry alone is not sufficient to exclude sphincter injury.     

Anal sphincter defects and anal incontinence symptoms after repair of obstetric anal sphincter lacerations in primiparous women

A study was carried out to identify (1) incidence of anal incontinence symptoms, (2) incidence and size of both external anal sphincter (EAS) and internal anal sphincter (IAS) defects, and (3) relationship between anal incontinence symptoms and IAS or EAS defect size after repair of an obstetric anal sphincter laceration. Forty-seven vaginally primiparous women underwent obstetric anal sphincter laceration repair. At 8–12 weeks postpartum, anal incontinence symptoms were assessed, and endoanal ultrasound was performed. At 1–2 years postpartum, symptoms were reassesseds. The incidence of anal incontinence symptoms at 8–12 weeks was 43%. The incidence of IAS and EAS defects were 32% and 77%, respectively. IAS defects ≥45 degrees were predictive of symptoms (p = 0.02). After 18 months mean follow-up, 11% reported chronic symptoms. After anal sphincter laceration repair, anal incontinence symptoms occur in 43% of women and remain chronic in 11%. Anal incontinence symptoms are associated with increasing IAS defect size. Poster presentation at the American Urogynecologic Society Annual Meeting, Hollywood, Florida, USA, 27–29 September 2007.     

Early results of immediate repair of obstetric third-degree tears: 65% are completely asymptomatic despite persistent sphincter defects in 61%

OBJECTIVE: The outcome of immediate repair of obstetric third-degree tears is poorly documented. Immediate repair may give better functional results than delayed repair because scarring is reduced. This aim of this prospective study was to examine the early outcome of immediate repair of third-degree tears. METHOD: A total of 121 women who had immediate repair of obstetric third-degree tears underwent interview, anal ultrasonography and anorectal physiology. RESULTS: At review, 79 (65%) were completely asymptomatic (score = 0), 23 (19%), had minor flatus incontinence or mild urgency causing no compromise to their quality of life (score 1-4), and 19 (16%) had clinically embarrassing faecal incontinence (score 5-24). Thirty-nine (32%) had an intact internal anal sphincter (IAS) and external anal sphincter (EAS) (i.e. a successful repair), eight (7%) had a defect in the IAS alone but the EAS was intact (i.e. a successful repair but a residual IAS defect), 43 (35%) had a residual defect in the EAS alone (IAS intact) and 31 (26%) had a persistent defect in the IAS and EAS. Residual defects in either or both of the sphincters were associated with a significantly higher incidence of abnormal resting and squeeze anal pressures. Anal manometry had no correlation with symptoms. The highest proportion of severe incontinence was in those with an IAS defect alone (37%) and when there was a residual IAS and EAS defect (24%). Only 2 of 39 (5%) with an intact IAS and EAS had severe incontinence and only 8 of 43 (18%) with a residual EAS defect alone had severe faecal incontinence. CONCLUSION: These results indicate a good outcome following immediate repair of third-degree obstetric tears and emphasize the role of the IAS in providing continence.     

Delayed sphincter repair for obstetric ruptures: Analysis of failure

Objective The aim of this study was to examine the clinical results after anterior anal sphincter repair in patients with obstetric trauma and to evaluate possible risk factors for poor outcome. Patients and methods In years 1990–99 anterior anal sphincter repair for anal incontinence due to obstetric trauma was performed in 39 patients at Helsinki University Central Hospital. Clinical examination with Parks' classification and patients' questionnaire with endoanal ultrasound (EAUS) were done before and after surgery. Pudendal nerve terminal motor latency (PNTML) was measured postoperatively. The median follow‐up time after the operation was 22 months (range 2–99). Results The follow‐up results of the patients' questionnaire for 12 patients (31%) were good, for 15 patients (38%) acceptable and for 12 patients (31%) poor. Postoperative EAUS showed sphincter overlap in 28 (72%) patients but a defect was still found in 11 (28%) patients. A defect found on postoperative EAUS correlated with poor clinical result according to Parks' (R = 0.8, P < 0.01) and patients' questionnaire results (R = 0.7, P < 0.01). Patients with poor clinical results (Parks III/IV) were statistically significantly older (median 63 years, range 26–73) than those with favourable results (Parks I/II) (median 45 years, range 27–79) (P < 0.05). Further, the duration of incontinence symptoms correlated with poor functional results (R = 0.4, P < 0.05). Conclusion After obstetric trauma anterior anal repair gives acceptable short‐term clinical results. EAUS investigation is easy and harmless to perform and should be used pre‐ and post‐operatively. Advanced age, pre‐operative signs of perineal descent, long‐lasting severe incontinence symptoms and a persistent defect on postoperative EAUS seem to be related to poor clinical result.     

Anorectal function evaluation and predictive factors for faecal incontinence in 600 patients

Aim Anorectal function was assessed in patients with and without faecal incontinence (FI) . Risk factors predictive for FI were determined. Method Between 2003 and 2009, all consecutive patients referred were assessed by questionnaire, anorectal manometry and anal endosonography. Predictive factors were identified and used to develop a statistical model to predict FI. Results Of 600 patients (519 women), 285 (48%) were faecally incontinent. In comparison with continent women, incontinent women (mean Vaizey score 15.4), were older, had more liquid stools, more deliveries, more urinary incontinence, lower anal pressures, shorter sphincter length, smaller rectal capacity and more sphincter defects. Incontinent men (mean Vaizey score 15.3) were older and had lower anal pressures. Incontinent and continent patients showed an overlap in test results. Predictors in women were age, stool consistency, anal pressures, rectal capacity, and internal and external sphincter defects. The area under the ROC‐curve was 0.84 (P < 0.001; 95% confidence interval, 0.80–0.87). Using a cut off point of 0.4, FI was predicted with sensitivity, specificity, positive and negative predictive values of 86%, 68%, 74% and 82%, respectively. The model was studied in five women with a temporary stoma and was accurate in predicting FI after stoma closure. Conclusion Incontinent patients have lower pressures, smaller rectal capacity and more sphincter defects than controls, but show a large overlap. Our model shows a relatively high sensitivity and negative predictive value for predicting FI in women. The model seems promising in the patients studied with a temporary stoma.     

Endosonographic evaluation of anal sphincters in healthy children

Purpose

To describe the endosonographic anatomy of anal sphincters in healthy children and to evaluate the reproducibility of sphincter thickness measurements.

Methods

Forty-five healthy children with median age of 3.6 years (range, 1.0-14.5 years) were studied while under general anesthesia for minor surgery. Anal endosonography was performed with a 7- to 10-MHz rotating transducer with a diameter of 19 mm. The internal anal sphincter (IAS) and the external anal sphincter (EAS) were assessed by 2 independent observers.

Results

IAS and EAS were identified in all children. The mean thickness of IAS and EAS were 1.3 mm and 5.3 mm, respectively. Identification of the inner and outer border of IAS was difficult, especially in children younger than 3 years. The thickness of EAS was easier to assess, and the interrater reliability for EAS thickness measurements was excellent. EAS thickness was positively correlated with the children's age. Reflectivity varied within the EAS with frequent hyporeflective areas.

Conclusions

Anal endosonography provided visualization of the IAS and EAS in children. Assessment of exact IAS thickness was difficult, especially in the youngest children. Mean EAS thickness was 5.3 mm, increasing with age. Hyporeflective areas of the intact EAS should not be misinterpreted as sphincter defects.     

Anal ultrasound and endosonographic measurement of perineal body thickness: a new evaluation for fecal incontinence in females

Background Perineal body thickness (PBT) is measured by endoanal ultrasonography. The literature has shown that women with obstetric trauma to the anal sphincter have decreased PBT, and a measurement of 10 mm or less has been proposed as abnormal. Therefore, this study aimed to compare the proposed definitions of normal to pathologic findings in patients with fecal incontinence (FI) and to correlate PBT with anorectal physiologic findings.Methods All female patients who had endoanal ultrasonography and PBT measurement for evaluation of FI were assessed and divided into three groups on the basis of PBT: 10 mm or less, 10 to 12 mm, more than 12 mm. The degree of FI (0 = complete continence; 20 = complete incontinence) was correlated with PBT.Results For this study, 83 female patients with a mean age of 59.7 years (range, 30–88 years) had endoanal ultrasonography and PBT measurement. Sphincter defects were suggested by endoanal ultrasonography in 77% of the patients in the three groups as follows: 57 (97%) of 59 patients, 4 (36%) of 11 patients, and 3 (23%) of 13 patients. The mean external sphincter defect angle was 110° (range, 45–170°), and the mean FI score was 13.8. For 89% of the patients there was a history of vaginal delivery. As reported, 35% had undergone one or more prior perineal surgeries, 27% had both, and 4% denied having had either. A significant correlation between sphincter defect and PBT (p < 0.001) was noted. External sphincter defect angles were negatively correlated with PBT (p = 0.001).Conclusion A PBT of 10 mm or less is considered abnormal, whereas a PBT of 10 mm to 12 mm is associated with sphincter defect in one-third of patients with FI. Those with a PBT of 12 mm or more are unlikely to harbor a defect unless they previously have undergone reconstructive perineal surgery.Supported in part by a grant from the Eleanor Naylor Dana Charitable Trust Fund. Poster presentation at the annual meeting of the Society of American Gastrointestinal Endoscopic Surgeons (SAGES) 13–16 March 2002, New York, NY, USA     

Faecal incontinence in men

Aim A few studies have specifically addressed faecal incontinence (FI) in men. We sought to describe patterns of male FI, assess treatment outcome and compare some aspects of FI between men and women, including quality of life. Method Prospectively recorded data on 85 consecutive male patients evaluated for FI at our pelvic floor centre in 2004 and 2005 were reviewed and compared with a cohort of 408 female patients. Treatment outcome in men was assessed by questionnaire. Results The aetiology of FI could be determined in 61 (72%) men and was most commonly related to anal surgery (n = 23), prostate cancer therapy (n = 9) and spinal injury (n = 9). Eight patients had idiopathic soiling only. Mean age, Fecal Incontinence Severity Index (FISI) and quality of life scores were similar between men and women. Maximal mean resting pressure (MRP) and squeeze pressure (MSP) were on average higher in men than in women [MRP 56.9 (26.2) vs 40 (20.4) mmHg; P < 0.0001]; [MSP 98.1 (67.3) vs 39.4 (28.5) mmHg; P < 0.0001]. Sphincter defects involved the external sphincter less often in men (35 vs 70%, P = 0.004). Differences in faecal incontinence quality of life (FIQL) and SF‐36 scores between men and women were minimal. After a median follow up of 2 years, complete resolution of symptoms was reported in 17% and improvement of symptoms in another 48% of men. Conclusion Although physiological and anatomical features of FI differ between men and women, its severity and impact on quality of life are similar. External sphincter defects are less common in men; hence, direct sphincter repair is less frequently an option. Evaluation and treatment improves symptoms in more than half of male patients.     

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

Background/PurposeFecal 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.MethodsSeventeen patients, divided into 3 groups according to Wingspread classification, underwent anorectal manometry and 3D-EAUS. Clinical, manometric, and endosonographic scoring systems were used.ResultsThe 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.ConclusionsLesions 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.     

Evaluation of the use of PTQTMimplants for the treatment of incontinent patients due to internal anal sphincter dysfunction

Objective This study reports the results of injectable silicone PTQ^TM implants for faecal incontinence due to internal anal sphincter (IAS) dysfunction. Method Twenty patients (12 women) with partial faecal incontinence aged from 55 to 65 years were treated by a PTQ^TM implant. All patients completed the Cleveland Clinic Continence and Quality of Life questionnaire. Endoluminal ultrasound and anorectal physiological testing were performed in each patient. All implants were inserted into the submucosal plane without ultrasound guidance. Results Faecal continence was significantly improved up to 1 year. The Wexner continence score fell from a median of 13.05 (range, 5–20) before treatment to 4.5 (range 2–7.7) at 1 month after (P < 0.005). This rose gradually to 6.2 (range, 0–16) at one year (P = 0.02) and 9.4 (range, 1–20) at 2 years (P = 0.127). There were no differences in resting or squeeze pressure before and at 3 months after treatment (P = 0.86 and P = 0.93). Fourteen (70%) patients experienced pruritus ani during the first few weeks after the procedure and one developed infection at the implant site. Conclusion Silicone implantation is minimally invasive and technically simple. It is effective over 1 year in the treatment of faecal incontinence due to IAS dysfunction.     

Anal canal anatomy showed by three-dimensional anorectal ultrasonography

Background Demonstrate precisely the anatomic configuration of the anal canal and the length and thickness of the anal sphincters using three-dimensional (3-D) anorectal ultra-sonography in both genders. Methods Twelve normal volunteer males and 14 females, with a mean age of 52.4 and 50.3 years, respectively, were prospectively enrolled in this study. All individuals from both groups were submitted to anorectal ultra-sonography. The anal canal was analyzed, measuring the length and thickness of the external anal sphincter (EAE), internal anal sphincter (IAS), puborectalis muscle (PR) and the gap (distance from the anterior EAS to the anorectal junction) in the midline longitudinal (ML) and transverse (MT) planes, and the results were compared between quadrants and genders. Results The distribution of sphincter muscles is asymmetric in both genders. The anterior upper anal canal is an extension of the rectal wall with all layers clearly identified. The anterior IAS is formed in the distal upper anal canal and is significantly shorter in female than in male in all quadrants. The anterior IAS length is shorter than the posterior and lateral in both genders. The anterior EAS length is significantly shorter (2.2 cm) and the gap is longer (1.2 cm) in female than in male (3.4 cm) (0.7 cm) (p < 0.05), respectively. The posterior and lateral EAS-PR is significant longer in males (3.6 cm) (3.9 cm) than in females (3.2 cm) (3.5 cm) (p < 0.05), respectively. The lateral EAS-PR is significant longer than the posterior part in both genders. The anterior IAS is significantly thicker in males (0.19 cm) than in females (0.12 cm) (p = 0.04). Conclusion 3-D anal endosonography enabled measurement of the different anatomical structures of the anal canal and demonstrated its asymmetrical configuration. The shorter anterior EAS and IAS associated with a longer gap could justify the higher incidence of pelvic floor dysfunction in females, especially fecal incontinence and anorectocele with rectal intussusception.     

Accuracy of the digital anal examination in women with fecal incontinence

Introduction and hypothesis

This study aims to determine the accuracy of digital rectal examination (DRE) to detect anal sphincter defects when compared to endoanal ultrasound (US) in women with fecal incontinence (FI).

Methods

Seventy-four patients identified by retrospective chart review who presented with complaints of bothersome FI who underwent endoanal US are the subjects of this analysis. Sensitivity, specificity, and positive and negative likelihood ratios were calculated for the ability of the DRE to detect anal sphincter defects.

Results

Anal sphincter defect was suspected on DRE in 75%. At endoanal US, external sphincter defects were noted in all three segments in 41% (complete defect) while partial defects were noted in 30%. DRE demonstrated a sensitivity of 82%, specificity of 32%, +likelihood ratio 1.2 (95% confidence interval (CI), 0.95–1.16) and ?likelihood ratio of 0.6 (95% CI, 0.2–1.24) for detecting a complete EAS defect on endoanal US.

Conclusion

DRE has poor specificity for detecting anal sphincter defects seen on endoanal US.     

Effect of vaginal delivery on anal sphincter function in Asian primigravida: a prospective study

Introduction and hypothesis

The true incidence of obstetric anal sphincter injuries (OASI) among Asian primigravida is not known. This study aimed to evaluate OASI in Sri Lankan primigravida.

Methods

One hundred and one consecutive primigravida in their last trimester were recruited from antenatal clinics at a tertiary care centre in Sri Lanka and followed up 6 weeks and 6 months after delivery. They were assessed using anorectal manometry (3D-ARM) and endoanal ultrasound (3D-EAUS) on both occasions.

Results

Seventy-three (75.3 %) had vaginal delivery without instrumentation, whereas 3 (3.1 %) each delivered using forceps or vacuum. Twelve (12.4 %) had emergency caesarean sections and 6 (6.2 %) had elective caesarean sections. None had clinically identified anal sphincter injuries. EAUS identified IAS defects in 3 (5.1 %) and EAS defects in 28 (47.5 %). Both resting (p?=?0.3) and squeeze (p?=?0.001) pressures had decreased following childbirth. Multivariate analysis identified antepartum RP and postpartum EAS defects to be associated with RP reduction (χ²(4)=17.825, p?<?0.0005) and antepartum SP and postpartum EAS defects to be associated with SP reduction (χ²(5)=31.517, p?<?0.0005). Episiotomy was protective, whereas delivering after 40 weeks’ gestation and delivering a baby with a longer length increased the risk of SP reduction. EAS defects (χ² (6)=23.502, p?=?.001) were more common in mothers who had labour augmented by oxytocin and in those who delivered a baby with a larger head circumference. Labour induction and delivering a longer baby were protective for EAS defects.

Conclusions

Several risk and protective factors for the structural and functional damage of sphincters were identified. These findings will help to formulate a policy to minimize future obstetric anal sphincter injuries.

     

A contraction response of the internal anal sphincter to Botulinum toxin: does low‐pressure chronic anal fissure have a different pathophysiology?

Aim A subset of low‐pressure fissures is not associated with typical internal anal sphincter hypertonia and may involve a different pathophysiological mechanism. We aimed to assess the manometric response of the internal anal sphincter to botulinum toxin in low‐pressure fissures compared to high‐pressure fissures. Method Twenty five units of botulinum toxin (Botox^TM) were injected directly into the internal anal sphincter. Maximum resting pressure (MRP) and maximum squeeze increment (MSI) were documented at baseline and four weeks after injection. Results Nine (31%) of 29 patients had a low‐pressure fissure. Those with an anterior fissure had a significantly lower median baseline MRP than those with a posterior fissure (66 vs 83 mmHg, P = 0.009). Significantly more patients with low‐pressure fissures developed a contraction or no response (78%vs 30%, difference 48%, 95% CI 14–82%, P = 0.006). Those developing a contraction response had a lower mean baseline MRP than those developing a relaxation response (56 vs 86 mmHg, difference 30 mmHg, 95% CI 17–43%, P < 0.001). Conclusion Botulinum toxin appears to have an atypical contraction effect on the internal anal sphincter in low‐pressure (usually anterior) fissures. This may be accounted for by blockade of acetylcholine released at parasympathetic nerve terminals and the sympathetic ganglion (relaxation). Low pressure fissures may be physiologically different from high‐pressure fissures.     

Faecal incontinence after lateral internal sphincterotomy is often associated with coexisting occult sphincter defects: a study using endoanal ultrasonography

Background : Troublesome faecal incontinence following a lateral internal sphincterotomy (LIS) is often attributed to faulty surgical techniques: division of excessive amount of internal sphincter or inadvertent injury to the external sphincter. The aim of the present paper was to assess the anatomic and physiological factors that may contribute to faecal incontinence following a technically satisfactory lateral internal sphincterotomy by a group of colorectal specialists. Methods : Fourteen patients (nine women, five men; median age: 38 years; range: 23–52 years) who developed troublesome postoperative faecal incontinence were evaluated by clinical assessment, endoanal ultrasonography and anorectal physiological studies (manometry, pudendal nerve terminal motor latency) by two independent observers. The Cleveland Clinic continence score (0–20; 0, perfect continence; 20, complete incontinence) was used to quantify the severity of faecal incontinence. Fourteen continent subjects after a LIS (nine female patients, five male patients; median age: 36 years; range: 20–44 years) were also evaluated as ‘continent’ controls (continence score ≤ 4). Results : In the incontinent group, the median postoperative Cleveland Clinic continence score was 9 (range: 6–13) compared with a preoperative score of 1 (range: 0–3). On assessment by endoanal ultrasonography the site of the internal sphincterotomy was clearly identified. There were additional coexisting defects, on endoanal ultrasonography, of the external anal sphincter in seven female patients, of the internal sphincter in two female and two male patients; and a defect of both the external and internal sphincters in a male patient who had had a prior fistulotomy. The pudendal nerve terminal motor latency (PNTML) was prolonged in two female patients on the side contralateral to the lateral internal sphincterotomy. In two of five male patients there was no evidence of any occult sphincter injuries. In the continent controls a defect of the distal portion of the external sphincter was noted in one female patient. None of the patients had a prolonged PNTML. The maximum voluntary contraction was significantly lower in the female subjects than in the female continent controls (92 mmHg vs 140 mmHg; P < 0.05), while the resting anal canal pressures and length of the high pressure zone were similar between the study subjects and the continent controls. Conclusion : Troublesome faecal incontinence after a satisfactorily performed lateral internal sphincterotomy is often associated with coexisting occult sphincter defects.