Traditional measures of normal anal sphincter function using high-resolution anorectal manometry (HRAM) in 115 healthy volunteers

Characterization of Anal Slow Waves and Ultraslow Waves in Patients With Constipation and Healthy Subjects

BACKGROUND

Anal slow waves (SW) and ultraslow waves (USW) have been documented previously, yet their significance remains uncertain. Our aims were to characterize the prevalence and features of SW and USW in healthy subjects and patients with constipation and to correlate them with clinical features and anorectal physiological testing.

METHODS

Forty-three healthy female subjects and 83 female tertiary referral patients with constipation were included. High-resolution water-perfused manometry was performed. Retrospective blinded descriptive and quantitative analyses of manometric tracings were completed with a focus on SW and USW.

KEY RESULTS

SW were present in 58% of healthy subjects and 62% of constipated patients (p = 0.72) yet USW were seen almost exclusively in constipated patients (27% vs. 2% health; p < 0.0001). Frequencies and mean amplitudes of SW and USW were similar in both groups. Anal resting and squeeze pressures were higher in patients with SW compared to those without (p < 0.001, p = 0.004, respectively). Patients with USW had higher anal resting pressure and shorter duration of sustained squeeze compared to those without (p < 0.001 for both). There was a trend for less obstetric injury in constipated patients with USW compared to those without (23% vs. 48%; p = 0.05).

CONCLUSIONS AND INTERFERENCES

While SW were common in both constipated and healthy subjects, USW were almost exclusively observed in constipated patients. Some correlations were observed with other anorectal physiology parameters such as high resting anal pressure with both SW and USW. Formal definitions for SW and USW are proposed. Further research into the clinical significance of these waves is warranted.

Provocative tests of anal sphincter function correlate with symptoms and subtypes of faecal incontinence

OBJECTIVES

High-resolution anorectal manometry (HRAM) is the established investigation in faecal incontinence (FI). However, provocative tests (functional lumen imaging probe (FLIP) and anal acoustic reflectometry (AAR)) have been proposed as alternatives. This study uniquely explores all three methods in correlation with FI symptoms and subtypes.

METHODS

This was a prospective observational study of patients with FI attending a tertiary pelvic floor unit between August 2022 and January 2024. Patients underwent HRAM, FLIP and AAR with the order randomised. FI severity was assessed with the Vaizey score and quality-of-life with the Manchester Health Questionnaire.

RESULTS

40 patients (39 women, median age: 62 (range: 38-85)) were recruited with 27 (67.5%) reporting urge FI, 8 (20%) mixed and 5 (12.5%) passive incontinence. FLIP squeeze measurements correlated with the Vaizey score, including incremental squeeze pressure at 40 mL (rs=-0.412; p=0.008) and 50 mL (rs=-0.414; p=0.009) and the pressure-diameter volume loop at 50 mL (rs=-0.402; p=0.011). Incremental squeeze opening pressure with AAR correlated with the Vaizey score (rs=-0.339; p=0.032). There was no correlation between symptom severity and HRAM parameters, or any parameter and quality-of-life scores. Resting parameters with all three modalities were lower in passive FI: mean resting pressure (HRAM; p=0.010), yield pressure (FLIP; p=0.031) and opening pressure (AAR; p=0.006). With FLIP, there was a trend towards reduced squeeze function in the urge group (pressure-diameter volume loop at 50 mL; p=0.295).

CONCLUSIONS

FLIP and AAR correlate better with FI symptoms compared with HRAM. Therefore, these provocative tests could be used to guide the management of FI in prospective studies.

Frequency of detection of dyssynergic defecation in patients with overlap syndrome of functional disorders of the digestive organs associated with constipation

Introduction. The presence of dyssynergic defecation in a cohort of patients with overlap syndrome of functional disorders is poorly studied.

Aim. To assess the motor function and sensitivity parameters of the anorectal zone, to identify dyssynergic defecation and to analyze the frequency of correlation in patients with overlap syndrome of functional gastrointestinal disorders associated with constipation.

Materials and methods. A one-stage examination was conducted in four parallel groups. The study included 100 patients aged 30 to 40 years with the following diagnoses: constipation-p redominance irritable bowel syndrome (IBS-C) (group 1), IBS-C combined with functional dyspepsia (group 2), IBS-C combined with functional biliary disorder (group 3) and healthy volunteers (group 0). All patients underwent a balloon expulsion test and high-resolution anorectal manometry to determine the presence of dyssynergic defecation.

Results. Based on the analysis of parameters according to anorectal manometry data, dyssynergic defecation was not detected in group 0, in group 1 dyssynergic defecation was detected in 8 people – 32.0% (95% CI 12.3–51.6), in group 2 – in 14 people – 56.0% (95% CI 35.0–76.9), in group 3 – in 16 people – 64.0% (95% CI 43.7–84.2). A negative evacuation test was detected in 8 (32%) patients in group 1, in 14 (56%) patients in group 2, and in 17 (68%) patients in group 3, which confirmed the presence of dyssynergic defecation.

Conclusions. This study demonstrated the presence of dyssynergic defecation in three groups of subjects, more often with a combination of irritable bowel syndrome with predominant constipation with functional dyspepsia, and most often with a functional disorder of the gallbladder.

Effect of neoadjuvant chemoradiation on anorectal function assessed with anorectal manometry: A systematic review and meta-analysis

AIM

Improvement in oncological survival for rectal cancer increases attention to anorectal dysfunction. Diagnostic questionnaires can evaluate quality of life but are subjective and dependent on patients' compliance. Anorectal manometry can objectively assess the continence mechanism and identify functional sphincter weakness and rectal compliance. Neoadjuvant chemoradiotherapy is presumed to affect anorectal function. We aim to assess anorectal function in rectal cancer patients who undergo total mesorectal excision, with or without neoadjuvant chemoradiation, using anorectal manometry measurements.

METHOD

MEDLINE, Embase, and Cochrane databases were searched for studies comparing perioperative anorectal manometry between neoadjuvant chemoradiation and upfront surgery for rectal cancers. Primary outcomes were resting pressure, squeeze pressure, sensory threshold volume and maximal tolerable volume.

RESULTS

Eight studies were included in the systematic review, of which seven were included for metanalysis. 155 patients (45.3%) had neoadjuvant chemoradiation before definitive surgery, and 187 (54.6%) underwent upfront surgery. Most patients were male (238 vs. 118). The standardized mean difference of mean resting pressure, mean and maximum squeeze pressure, maximum resting pressure, sensory threshold volume, and maximal tolerable volume favored the upfront surgery group but without statistical significance.

CONCLUSION

Currently available evidence on anorectal manometry protocols failed to show any statistically significant differences in functional outcomes between neoadjuvant chemoradiation and upfront surgery. Further large-scale prospective studies with standardized neoadjuvant chemoradiation and anorectal manometry protocols are needed to validate these findings.

A comparison of function lumen imaging probe measurements of anal sphincter function in fecal incontinence

BACKGROUND

The functional lumen imaging probe (FLIP) is a test of anal sphincter distensibility under evaluation by specialist centers. Two measurement protocols termed "stepwise" and "ramp" are used, risking a lack of standardization. This study aims to compare the performance of these protocols to establish if there are differences between them.

METHODS

Patients with fecal incontinence were recruited and underwent measurement with both protocols at a tertiary pelvic floor referral unit. Differences in minimum diameter, FLIP bag pressure, and distensibility index (DI) at rest and during squeeze were calculated at various FLIP bag volumes.

KEY RESULTS

Twenty patients (19 female, mean age 61 [range: 38-78]) were included. The resting minimum diameter at 30 and 40 mL bag volumes were less in the stepwise protocol (mean bias: -0.55 mm and -1.18 mm, p < 0.05) along with the DI at the same bag volumes (mean bias: -0.37 mm2/mmHg and -0.55 mm2/mmHg, p < 0.05). There was also a trend towards greater bag pressures at 30 mL (mean bias: +2.08 mmHg, p = 0.114) and 40 mL (mean bias: +2.81 mmHg, p = 0.129) volumes in the stepwise protocol. There were no differences between protocols in measurements of minimum diameter, maximum bag pressure, or DI during voluntary squeeze (p > 0.05).

CONCLUSION AND INFERENCES

There are differences between the two commonly described FLIP measurement protocols at rest, although there are no differences in the assessment of squeeze function. Consensus agreement is required to agree the most appropriate FLIP measurement protocol in assessing anal sphincter function.

London Protocol under water-perfused HRM in a healthy population, towards novel 3D manometric parameters in an evaluation of anorectal functional disorders

BACKGROUND/AIM

London Protocol (LP) and Classification allied to high-resolution manometry (HRM) technological evolution has updated and enhanced the diagnostic armamentarium in anorectal disorders. This study aims to evaluate LP reproducibility under water-perfused HRM, provide normal data and new parameters based on 3D and healthy comparison studies under perfusional HRM.

METHODS

Fifty healthy (25 F) underwent water-perfused 36 channel HRM based on LP at resting, squeeze, cough, push, and rectal sensory. Additional 3D manometric parameters were: pressure-volume (PV) 104mmHg2.cm (resting, short and long squeeze, cough); highest and lowest pressure asymmetry (resting, short squeeze, and cough). Complementary parameters (CP) were: resting (mean pressure, functional anal canal length); short squeeze (mean and maximum absolute squeeze pressure), endurance (fatigue rate, fatigue rate index, capacity to sustain); cough (anorectal gradient pressure); push (rectum-anal gradient pressure, anal canal relaxation percent); recto-anal inhibitory reflex (anal canal relaxation percent).

RESULTS

No difference to genders: resting (LP, CP, and 3D); short squeeze (highest pressure asymmetry); endurance (CP); cough (CP, highest and lowest pressure asymmetry); push (gradient pressure); rectal sensory. Higher pressure in men: short squeeze (maximum incremental, absolute, and mean pressure, PV, lowest pressure asymmetry); long squeeze (PV); cough (anal canal and rectum maximum pressure, anal canal PV); push (anal canal and rectum maximum pressure). Anal canal relaxation was higher in women (push).

CONCLUSIONS

LP reproducibility is feasible under water-perfused HRM, and comparative studies could bring similarity to dataset expansion. Novel 3D parameters need further studies with healthy and larger data to be validated and for disease comparisons.

KEY POINTS

• London Protocol and Classification allied with the technological evolution of HRM (software and probes) has refined the diagnostic armamentarium in anorectal disorders. • Novel 3D and deepening the analysis of manometric parameters before the London Classification as a contributory diagnostic tool. • Comparison of healthy volunteers according to the London Protocol under a perfusional high-resolution system could establish equivalence points.

Short-term clinical and manometric outcomes of percutaneous tibial nerve stimulation for faecal incontinence: a large single-centre series

BACKGROUND

Faecal incontinence (FI) is common, with a significant impact on quality of life. Percutaneous tibial nerve stimulation (PTNS) is a therapy for FI; however, its role has recently been questioned. Here we report the short-term clinical and manometric outcomes in a large tertiary centre.

METHODS

A retrospective review of a prospective PTNS database was performed, extracting patient-reported FI outcome measures including bowel diary, the St Marks's Incontinence Score (SMIS) and Manchester Health Questionnaire (MHQ). Successful treatment was > 50% improvement in symptoms, whilst a partial response was 25-50% improvement. High-resolution anorectal manometry (HRAM) results before and after PTNS were recorded.

RESULTS

Data were available from 135 patients [119 (88%) females; median age: 60 years (range: 27-82years)]. Overall, patients reported a reduction in urge FI (2.5-1) and passive FI episodes (2-1.5; p < 0.05) alongside a reduction in SMIS (16.5-14) and MHQ (517.5-460.0; p < 0.001). Some 76 (56%) patients reported success, whilst a further 20 (15%) reported a partial response. There were statistically significant reductions in rectal balloon thresholds and an increase in incremental squeeze pressure; however, these changes were independent of treatment success.

CONCLUSION

Patients report PTNS improves FI symptoms in the short term. Despite this improvement, changes in HRAM parameters were independent of this success. HRAM may be unable to measure the clinical effect of PTNS, or there remains the possibility of a placebo effect. Further work is required to define the role of PTNS in the treatment of FI.

A Mechanics-Based Perspective on the Function of Human Sphincters During Functional Luminal Imaging Probe Manometry

Functional luminal imaging probe (FLIP) is used to measure cross-sectional area (CSA) and pressure at sphincters. It consists of a catheter surrounded by a fluid filled cylindrical bag, closed on both ends. Plotting the pressure-CSA hysteresis of a sphincter during a contraction cycle, which is available through FLIP testing, offers information on its functionality, and can provide diagnostic insights. However, limited work has been done to explain the mechanics of these pressure-CSA loops. This work presents a consolidated picture of pressure-CSA loops of different sphincters. Clinical data reveal that although sphincters have a similar purpose (controlling the flow of liquids and solids by opening and closing), two different pressure-CSA loop patterns emerge: negative slope loop (NSL) and positive slope loop (PSL). We show that the loop type is the result of an interplay between (or lack thereof) two mechanical modes: (i) neurogenic mediated relaxation of the sphincter muscle or pulling applied by external forces, and (ii) muscle contraction proximal to the sphincter which causes mechanical distention. We conclude that sphincters which only function through mechanism (i) exhibition NSL whereas sphincters which open as a result of both (i) and (ii) display a PSL. This work provides a fundamental mechanical understanding of human sphincters. This can be used to identify normal and abnormal phenotypes for the different sphincters and help in creating physiomarkers based on work calculation.

Clinical utility of anal sphincter relaxation integral in water-perfused and solid-state high-resolution anorectal manometry

BACKGROUND/PURPOSE

We investigated the diagnostic performance of the anal sphincter relaxation integral (ASRI) for infants with Hirschsprung's disease (HD).

METHODS

We performed water-perfused high-resolution anorectal manometry (HRAM) in 18 infants (9 with HD), and solid-state HRAM in another 18 infants (4 with HD). We calculated the ASRI during the rectoanal inhibitory reflex (RAIR) maneuver at pressure cutoffs of <10 mmHg (ASRI 10) and <15 mmHg (ASRI 15). We investigated the diagnostic performance of the ASRI for HD in infants undergoing water-perfused and solid-state HRAM.

RESULTS

HD infants who underwent either water-perfused or solid-state HRAM had significantly lower ASRI 10 and ASRI 15 values, compared with non-HD infants (P < 0.05 and P < 0.05, respectively). Using the water-perfused HRAM system, ASRI 10 and ASRI 15 values of <7 and <29 mmHg s.cm, respectively, exhibited good diagnostic performance for HD (88.89% and 88.89%, respectively). Receiver operating characteristic curve analysis indicated that ASRI 10 and ASRI 15 values of <5.5 and <20 mmHg s.cm, respectively, were optimal for the diagnosis of HD infants when using the solid-state HRAM system, with high diagnostic accuracies of 83.33% and 83.33%, respectively.

CONCLUSION

ASRI may assist the diagnosis of HD infants using either water-perfused or solid-state HRAM. These systems require different catheter-specific ASRI cutoffs for the prediction of HD.

High-resolution anorectal manometry for diagnosing obstructed defecation syndrome associated with moderate rectocele compared to healthy individuals

BACKGROUND

Few studies have investigated healthy female individuals (HFI) and those with obstructed defecation syndrome associated with moderate rectocele in women (MRW), identified using three-dimensional high-resolution anorectal manometry (3D HRAM) parameters that correlate with age stratification.

OBJECTIVE

We aimed to explore the clinical diagnostic values of the MRW and HFI groups using 3D HRAM parameters related to age stratification.

METHODS

A prospective non-randomized controlled trial involving 128 cases from the MRW (treatment group, 68 cases) and HFI (control group, 60 cases) groups was conducted using 3D HRAM parameters at Tianjin Union Medical Center between January 2017 and June 2022, and patients were divided into two subgroups based on their ages: the ≥50 and < 50 years subgroups.

RESULTS

Multivariate binary logistic regression analysis showed that age (P = 0.024) and rectoanal inhibitory reflex (P = 0.001) were independent factors affecting the disease in the MRW group. Compared to the HFI group, the receiver operating characteristic (ROC) curve demonstrated that the 3D HRAM parameters exhibited a higher diagnostic value for age (Youden index = 0.31), urge to defecate (Youden index = 0.24), and rectoanal pressure differential (Youden index = 0.21) in the MRW group.

CONCLUSIONS

Compared to the HFI group, the ROC curve of the 3D HRAM parameters suggests that age, urge to defecate, and rectoanal pressure differential in the MRW group have a significant diagnostic value. Because the Youden index is lower, 3D HRAM cannot be considered the gold standard method for diagnosing MRW.

Preservation of the inferior mesenteric artery VS ligation of the inferior mesenteric artery in left colectomy: evaluation of functional outcomes-a prospective non-randomized controlled trial

Vascular approach during elective laparoscopic left colectomy impacts post-operative outcomes. The aim of our study was to evaluate how different approaches impact positively defecatory, urinary and sexual functions and quality of life during elective laparoscopic left colectomy. A prospective non-randomized controlled trial at two tertiary center was conducted. All patients who underwent elective laparoscopic left colonic resection from January 2019 to July 2022 were analyzed. They were divided into two groups based on Inferior Mesenteric Artery (IMA) preservation with distal ligation of sigmoid branches close to a colonic wall for complicated diverticular disease and IMA high tie ligation for oncological disease. Patients were asked to fulfil standardized, validated questionnaires to evaluate pre and post-operative defecatory, urinary and sexual functions and quality of life. Defecatory disorders were assessed by high-resolution anorectal manometry preoperatively and six months after surgery. A total of 122 patients were included in the study. The 62 patients with IMA preservation showed a lower incidence of defecatory disorders also confirmed by manometer data, minor incontinence and less lifestyle alteration than the 60 patients with IMA high tie ligation. No urinary disorders such as incomplete emptying, frequency, intermittence or urgency were highlighted after surgery in the IMA preservation group. Evidence of any sexual disorders remained controversial. The IMA-preserving vascular approach seems to be an effective strategy to prevent postoperative functional disorders. It is a safe and feasible technique especially for diverticular disease. New prospective randomized and highly probative studies are needed to confirm the effectiveness in specific clinical situations.

Study on 3D High-Resolution Anorectal Manometry Interrater Agreement in the Evaluation of Dyssynergic Defecation Disorders

Anorectal manometry measurements exhibit significant interrater variability. Newer techniques like 3D high-resolution anorectal manometry (3D-HRAM) have the potential to enhance diagnostic accuracy and our understanding of defecation disorders. However, the extent of interrater variability in 3D-HRAM is still unknown. Between January 2020 to April 2022, patients referred for pelvic floor physical therapy (PFPT) due to functional defecation complaints underwent 3D-HRAM testing. In a retrospective analysis, three expert raters independently evaluated the 3D-HRAM results in a blinded matter to assess interrater agreement. The evaluation also determined the level of agreement concerning dyssynergic patterns during simulated defecation. The 3D-HRAM results of 50 patients (37 females) were included. Twenty-nine patients had complaints of fecal incontinence, eleven patients had chronic constipation, and ten patients had several other complaints. There was a substantial agreement (kappa 0.612) between the raters concerning the 3D images on dyssynergic patterns during simulated defecation. Our study emphasizes the need for standardized guidelines in evaluating 3D-HRAM test results to reduce subjectivity and further improve agreement among raters. Implementing these guidelines could improve diagnostic consistency and enhance personalized treatment strategies, increasing the reliability and usefulness of 3D-HRAM testing in clinical practice.

Age- and Gender-Based Differences in Anorectal Function, Gastrointestinal Symptoms, and Constipation-Specific Quality of Life in Patients with Chronic Constipation

BACKGROUND

The effect of age and gender differences on anorectal function, symptoms severity, and quality of life (QoL) in patients with chronic constipation (CC) is not well studied. This study examines the impact of age and gender on anorectal function testing (AFT) characteristics, symptoms burden, and QoL in patients with CC.

METHODS

This is a retrospective analysis of prospectively collected data from 2550 adults with CC who completed AFT. Collected data include demographics, sphincter response to simulated defecation during anorectal manometry (ARM), balloon expulsion testing (BET), and validated surveys assessing constipation symptoms and QoL. DD was defined as both the inability to relax the anal sphincter during simulated defecation and an abnormal BET.

RESULTS

2550 subjects were included in the analysis (mean age = 48.6 years). Most patients were female (81.6%) and Caucasian (82%). 73% were < 60 years old (mean = 41) vs. 27% ≥ 60 years old (mean = 69). The prevalence of impaired anal sphincter relaxation on ARM, abnormal BET, and DD in patients with CC was 48%, 42.1%, and 22.9%, respectively. Patients who were older and male were significantly more frequently diagnosed with DD and more frequently had impaired anal sphincter relaxation on ARM, compared to patients who were younger and female (p < 0.05). Conversely, CC patients who were younger and female reported greater constipation symptoms severity and more impaired QoL (p ≤ 0.004).

CONCLUSION

Among patients with CC referred for anorectal function testing, men and those older than 60 are more likely to have dyssynergic defecation, but women and patients younger than 60 experience worse constipation symptoms and QoL.

Recto-anal Pressures in Constipated Men and Women Undergoing High-Resolution Anorectal Manometry

BACKGROUND

In constipated individuals, high-resolution anorectal manometry (HRM) may suggest the presence of a defecatory disorder. Despite known physiological differences between men and women, our understanding of functional anorectal pathophysiology is based upon predominantly female cohorts. Results are generalized to men.

AIMS

To evaluate whether recto-anal pressure patterns in constipated men are similar to those in constipated women.

METHODS

The electronic health records at Mayo Clinic, Rochester were used to identify constipated adult patients, without organic anorectal disease, who had undergone HRM and balloon expulsion testing (BET) in 2018, 2019, and 2020. Comparative analyses were performed.

RESULTS

Among 3,298 constipated adult patients (2,633 women, 665 men), anal and rectal pressures were higher in men. Women more likely to have HRM findings suggestive of a defecatory disorder (39% versus 20%, P < 0.001). Women were more likely to exhibit a type 4 pattern (27% versus 14%, P < 0.001), and less likely to exhibit a type 1 pattern (14% versus 38%, P < 0.001), of dyssynergia. Men were more likely to have an abnormal balloon expulsion test (BET, 34% versus 29%, P = 0.006). Nominal logistic regression demonstrates that male sex, age over 50 years, reduced recto-anal gradient during simulated evacuation, and types 2 and 4 dyssynergia are associated with an abnormal BET.

CONCLUSIONS

In this large retrospective study, constipated men and women exhibited different patterns of dyssynergia both in the presence and absence of an abnormal BET. These findings were independent of sex-specific baseline physiological differences.

Results of Anorectal Physiological Testing in Patients with Limited English Proficiency

BACKGROUND

Patients with limited English proficiency (LEP) experience barriers to healthcare. These include language barriers and difficulty accessing medical subspecialties. Consequently, patients with LEP may be underrepresented, and may be more likely to have abnormal results, among individuals referred for anorectal testing.

AIMS

To explore whether differences exist in the results of high-resolution anorectal manometry (HRM), rectal sensory testing (RST), and balloon expulsion testing (BET) between patients with LEP and English proficiency (EP).

METHODS

The electronic health records at Mayo Clinic, Rochester were used to identify constipated patients without organic anorectal disease who had undergone anorectal testing in 2018, 2019, and 2020. The language spoken by the patients was determined. HRM, RST, and BET results were compared. Nominal logistic regression explored the influence of age, gender, test operator, and LEP on the likelihood of abnormal findings.

KEY RESULTS

Among 3298 patients (80% female, mean age ± standard deviation 46 ± 16 years), 67 (2%) had LEP. HRM measurements were similar in LEP and EP patients. However, LEP patients were more likely to have abnormal BET and RST. Logistic regression revealed that age (older than 50 years), gender, test operator, and LEP influenced the results of BET and RST, with LEP having the strongest influence.

CONCLUSIONS

Results of anorectal testing in constipated patients differ between LEP and EP patients. This is likely to represent a difference in disease prevalence between these groups, for example, due to referral bias, rather than a difference in physiology or a language barrier.

To what extent are anorectal function tests comparable? A study comparing digital rectal examination, anal electromyography, 3-dimensional high-resolution anal manometry, and transperineal ultrasound

BACKGROUND

Anorectal function tests are helpful for objective investigation of anorectal (dys)function. A variety of tests are available, but there is no recommendation when to perform which test. Furthermore, which test is the most accurate is controversial and the correlation between these tests is not very clear. The aim of our study was to examine the correlation of anal pressures and the possibility to diagnose pelvic floor dyssynergia between digital rectal examination (DRE) and several anorectal function tests.

METHODS

Between January 2020 and April 2022, all men and women aged 18 to 80 years, treated at the Proctos Clinic, who were referred for pelvic floor physical therapy (PFPT) by the surgeon and underwent anorectal function tests, were included. DRE was performed to establish the anal pressure at rest and during squeeze and straining. Anorectal function tests included 3D high-resolution anal manometry (3D-HRAM), balloon expulsion test (BET), transperineal ultrasound (TPUS), and surface electromyography (s-EMG).

RESULTS

A total of 50 patients, 37 (74%) females, were included. Median age was 51 years. Twenty-three (62%) females had a history of two or more vaginal deliveries. The most frequent reason for referral for PFPT was fecal incontinence in 27 (54%) patients. The assessed pressures and pelvic floor function measured with DRE by the surgeon and the pelvic floor physical therapist during rest, squeeze, and straining correlated in 78%, 78%, and 84%, respectively. Correlation between DRE and 3D-HRAM or s-EMG was better for squeeze pressures than resting pressures. The correlation between s-EMG and 3D-HRAM was better during squeeze than at rest with an agreement of 59% and 37%, respectively.

CONCLUSION

DRE by an experienced investigator is of sufficient value for daily clinical practice to detect dyssynergia and to measure sphincter tone. Commonly performed anorectal function tests correlate poorly with DRE and with other anorectal function tests. When conservative treatment fails, further investigation is warranted; however, these results should be interpreted with caution. WHAT DOES THIS PAPER ADD TO THE LITERATURE?: Anorectal function tests such as the 3D high-resolution anorectal manometry, balloon expulsion test, surface electromyography, and transperineal ultrasound are all frequently performed in the diagnostic workup in patients with defecation disorders. No previous study has compared these tests regarding their outcomes, nor has the interrater agreement been measured regarding the digital rectal examination by two experienced observers. Furthermore, transperineal ultrasound is in all probability not frequently used and therefore underexposed in the diagnostic workup of patients with dyssynergic defecation.

Effects of Aging and Gender on the Anorectal Function of Healthy Subjects Assessed with Conventional Anorectal Manometry

Background/Aims

Anorectal functions are influenced by gender and age. This study sought to define the normal anorectal pressure values measured with conventional anorectal manometry (ARM) and to evaluate the effects of age and gender on anorectal function in asymptomatic subjects.

Methods

Conventional ARM was used to measure the anorectal pressures of 164 asymptomatic healthy subjects, including 86 males and 76 females.

Results

The resting anal pressures of males and females aged >60 years were significantly lower than those ≤60 years (males, 44.09±14.22 vs. 57.45±17.69, p<0.001; females, 44.09±14.22 vs. 57.45±17.69, p<0.001). The anal high-pressure zone was significantly lower in older males than in younger males (2.42±0.93 vs. 2.82±0.739, p=0.048). In both age groups (<60 and ≥60 years), the anal squeezing pressures of males were significantly higher than those of females (<60 years old, 168.40±75.94 vs. 119.15±57.53, p=0.001; ≥60 years, 149.61±64.68 vs. 101.3±54.92, p=0.006).

Conclusions

The normal anorectal pressure values measured with ARM in males and females were different. Older males and females had lower anal resting pressures than those of the younger subjects, but squeezing pressure was not affected by age.

Flow simulations of rectal evacuation: towards a quantitative evaluation from video defaecography

Mechanistic understanding of anorectal (patho)physiology is missing to improve the medical care of patients suffering from defaecation disorders. Our objective is to show that complex fluid dynamics modelling of video defaecography may open new perspectives in the diagnosis of defaecation disorders. Based on standard X-ray video defaecographies, we developed a bi-dimensional patient-specific simulation of the expulsion of soft materials, the faeces, by the rectum. The model quantified velocity, pressure and stress fields during the defaecation of a neostool with soft stool-like rheology for patients showing normal and pathological defaecatory function. In normal defaecation, the proximal-distal pressure gradient resulted from both the anorectal junction which formed a converging channel and the anal canal. The flow of the neostool through these anatomical parts was dominated by its shear-thinning viscous properties, rather than its yield stress. Consequently, the evacuation flow rate was significantly affected by variations in pressure applied by the rectum, and much less by the geometry of the anorectal junction. Lastly, we simulated impaired defaecations in the absence of obvious obstructive phenomena. Comparison with normal defaecation allowed us to discuss critical elements which should lead to effective medical management.

Three dimension high-definition manometry in evaluation of anorectal function in 104 normal infants and children: A clinical study from China

BACKGROUND

We aimed to evaluate anorectal function of normal infants and children through three dimension high-definition anorectal manometry (3D ARM) to fill the research blank in this area.

METHODS

From November 2014 to January 2019, 104 normal infants and children among patients who underwent 3D ARM were divided into four groups according to age (≤1 month; >1 month to ≤1 year; >1 year to ≤4 years and >4 years) and reviewed. The following parameters were performed: the length of anorectal high-pressure zone (HPZ), the resting pressure of HPZ (HPZ-rest), the squeezing pressure of HPZ (HPZ-sqze), recto-anal inhibitory reflex (RAIR), and pressure distribution of the anal canal. Graphpad Prism 7.0 software was used for statistical analysis.

RESULTS

HPZ, HPZ-rest, and HPZ-sqze increased with age. There were differences in HPZ-rest and HPZ-sqze between the groups (p < 0.05). Sex had a significant effect on HPZ, but not on HPZ-rest and HPZ-sqze. The HPZ of males was higher than that of females among those ≤1 month old (p < 0.05). RAIR (-) was found in 17 patients (16%) for whom Hirschsprung's disease were excluded by biopsy, and these patients had regular defecation during follow-up. Most of the patients (85%) older than 1 year had a symmetric anal pressure distribution during the contracting period (p < 0.05).

CONCLUSIONS

Anal canal function parameters gradually increased with age in normal infants and children which demonstrated the important role of age in evaluation, and these parameters can provide a reference for postoperative evaluation of anal canal function.

Review of the indications, methods, and clinical utility of anorectal manometry and the rectal balloon expulsion test

BACKGROUND

Anorectal manometry (ARM) comprehensively assesses anorectal sensorimotor functions.

PURPOSE

This review examines the indications, techniques, interpretation, strengths, and weaknesses of high-resolution ARM (HR-ARM), 3-dimensional high-resolution anorectal manometry (3D-HR-ARM), and portable ARM, and other assessments (i.e., rectal sensation and rectal balloon expulsion test) that are performed alongside manometry. It is based on a literature search of articles related to ARM in adults. HR-ARM and 3D-HR-ARM are useful for diagnosing defecatory disorders (DD), to identify anorectal sensorimotor dysfunction and guide management in patients with fecal incontinence (FI), constipation, megacolon, and megarectum; and to screen for anorectal structural (e.g., rectal intussusception) abnormalities. The rectal balloon expulsion test is a useful, low-cost, radiation-free, outpatient assessment tool for impaired evacuation that is performed and interpreted in conjunction with ARM. The anorectal function tests should be interpreted with reference to age- and sex-matched normal values, clinical features, and results of other tests. A larger database of technique-specific normal values and newer paradigms of analyzing anorectal pressure profiles will increase the precision and diagnostic utility of HR-ARM for identifying abnormal mechanisms of defecation and continence.

Towards an assessment of rectal function by coupling X-ray defecography and fluid mechanical modelling

Despite the numerous available clinical investi-gation tests, the associated alteration of quality of life and the socio-economic cost, it remains difficult for physicians to identify the pathophysiological origins of defecation disorders and therefore to provide the appropriate clinical care. Based on standardized dynamic X-ray defecography, we developed a 2D patient-specific computational fluid dynamic model of rectal evacuation. X-ray defecography was carried out in a sitting position with a standardized paste whose yield stress matched that of soft human feces. The flow was simulated with lattice-Boltzmann methods for yield stress fluids and moving boundary conditions. The model was applied for a patient with a normal recto-anal function. We deduced from the flow field that the main flow resistance during the defecation was due to the extrusion of the paste through the anal canal. We calculated also from pressure and stress fields the spatio-temporal evolution of the wall normal stress. This latter highlighted a gradient from the proximal to the distal part of the rectum. We discussed how this new set of hydrodynamical and biome-chanical parameters could be interpreted to gain new insights on the physiology of defecation and to diagnose underlying evacuation disorders. Clinical relevance - If confirmed, our approach should allow clinicians to obtain other parameters from a classic clinical examination and thus better adapt the response of clinicians to the defecation disorders observed in patients.

Redundancy in the International Anorectal Physiology Working Group Manometry Protocol: A Diagnostic Accuracy Study in Fecal Incontinence

BACKGROUND

Anorectal manometry (ARM) is essential for identifying sphincteric dysfunction. The International Anorectal Physiology Working Group (IAPWG) protocol and London Classification provide a standardized format for performing and interpreting ARM. However, there is scant evidence to support timing and number of constituent maneuvers.

AIMS

To assess the impact of protocol modification on diagnostic accuracy in patients with fecal incontinence.

METHODS

Retrospective analysis of high-resolution ARM recordings from consecutive patients based on the current IAPWG protocol and modifications thereof: (1) baseline rest period (60 vs. 30 vs. 10 s); (2) number of abnormal short squeezes (SS) out of 3 (SS1/SS2/SS3) based on maximal incremental squeeze pressures over 5 s; (3) resting anal pressures (reflecting recovery) at 25-30 versus 15-20 s after SS1.

RESULTS

One hundred patients (86 F, median age 55 [IQR: 39-65]; median St. Mark's incontinence score 14 [10-17]) were studied. 26% and 8% had anal hypotonia and hypertonia, respectively. Compared with 60-s resting pressure, measurements had perfect correlation (κ = 1.0) over 30 s, and substantial correlation (κ = 0.85) over 10 s. After SS1, SS2, and SS3, 43%, 49%, and 46% had anal hypocontractility, respectively. Correlation was substantial between SS1 and SS2 (κ = 0.799) and almost perfect between SS2 and SS3 (κ = 0.9). Compared to resting pressure of 5 s before SS1, pressure recordings at 25-30 and 15-20 s after SS1 were significantly correlated.

CONCLUSIONS

A 30-s resting anal pressure, analysis of 2 short-squeezes with a 20-s between-maneuver recovery optimizes study duration without compromising diagnostic accuracy. These findings indicate the IAPWG protocol has redundancy.

Diagnostic Strategy and Tools for Identifying Defecatory Disorders

This article reviews the indications, techniques, interpretation, strengths, and weaknesses of tests (anal manometry, anal surface electromyography, rectal balloon expulsion test, barium and MRI defecography, assessment of rectal compliance and sensation, and colonic transit) that are used diagnose defecatory disorders in constipated patients. The selection of tests and the sequence in which they are performed should be individualized to and interpreted in the context of the clinical features. Because anorectal functions are affected by age, results should be interpreted with reference to age- and sex-matched normal values for the same technique.

High Anal Canal Pressure and Rectal Washouts Contribute to the Decrease of Anal Basal Pressure After Botulinum Toxin Injections in Paediatric Patients With Chronic Constipation

INTRODUCTION

Chronic constipation can be treated by injecting botulinum toxin into the anal sphincter to decrease anal basal pressure. To assess the effect of botulinum toxin, we investigated the factors that contribute to changes in anal basal pressure after injection.

METHODS

This was a retrospective study conducted in a tertiary hospital in the Netherlands. We included children with chronic constipation treated with botulinum toxin injections and measured anal basal pressure before and after each injection. Multivariable linear regression analyses were used.

RESULTS

We investigated 30 cases with idiopathic constipation. Their median age was 20.5 (7.75-53.25) months. Anal basal pressure decreased after injection in 20 cases. The mean decrease of anal basal pressure after injection was 18.17 ± 35.22 mmHg. The anal basal pressure change was linearly correlated with preinjection pressure (R ² = 0.593, P < 0.001). A significant decrease of pressure was observed in patients with preinjection pressure > 70 mmHg. Preinjection anal basal pressure (β = -0.913, P < 0.001) and rectal washouts (β = -21.015, P = 0.007) contributed significantly to pressure changes. Changes in anal basal pressure were also significantly associated with patients' weights (β = 0.512, 95% CI, 0.011-1.013) and sex (β = 22.971, 95% CI, 9.205-36.736).

CONCLUSIONS

Botulinum toxin significantly decreases anal basal pressure when preinjection pressure is higher than 70 mmHg. In patients with severely elevated anal basal pressure, we recommend rectal washouts to promote the decrease of anal basal pressure.

Anorectal dysfunction in multiple sclerosis patients: A pilot study on the effect of an individualized rehabilitation approach

BACKGROUND:

Anorectal dysfunction (ARD), especially bowel incontinence, frequently compromises the quality of life in multiple sclerosis (MS) patients. The effect of rehabilitation procedures has not been clearly established.

OBJECTIVE:

To determine the effect of an individualized rehabilitation approach on bowel incontinence and anorectal pressures.

METHODS:

MS patients with ARD underwent 6-months of individually targeted biofeedback rehabilitation. High resolution anorectal manometry (HRAM) and St. Mark’s Fecal Incontinence Scores (SMIS) were completed prior to rehabilitation, after 10 weeks of supervised physiotherapy, and after 3 months of self-treatment.

RESULTS:

Ten patients (50%) completed the study. Repeated measures analysis of variance (ANOVA) demonstrated significant improvement in the SMIS questionnaire over time [14.00 baseline vs. 9.70 after supervised physiotherapy vs. 9.30 after self-treatment (p = 0.005)]. No significant improvements over time were noted in any HRAM readings: maximal pressure [49.85 mmHg baseline vs. 57.60 after supervised physiotherapy vs. 60.88 after self-treatment (p = 0.58)], pressure endurance [36.41 vs. 46.89 vs. 49.95 (p = 0.53)], resting pressure [55.83, vs 52.69 vs. 51.84 (p = 0.704)], or area under the curve [230.0 vs. 520.8 vs. 501.9 (p = 0.16)].

CONCLUSIONS:

The proposed individualized rehabilitation program supports a positive overall effect on anorectal dysfunction in MS patients.

Understanding the physiology of human defaecation and disorders of continence and evacuation

The act of defaecation, although a ubiquitous human experience, requires the coordinated actions of the anorectum and colon, pelvic floor musculature, and the enteric, peripheral and central nervous systems. Defaecation is best appreciated through the description of four phases, which are, temporally and physiologically, reasonably discrete. However, given the complexity of this process, it is unsurprising that disorders of defaecation are both common and problematic; almost everyone will experience constipation at some time in their life and many will develop faecal incontinence. A detailed understanding of the normal physiology of defaecation and continence is critical to inform management of disorders of defaecation. During the past decade, there have been major advances in the investigative tools used to assess colonic and anorectal function. This Review details the current understanding of defaecation and continence. This includes an overview of the relevant anatomy and physiology, a description of the four phases of defaecation, and factors influencing defaecation (demographics, stool frequency/consistency, psychobehavioural factors, posture, circadian rhythm, dietary intake and medications). A summary of the known pathophysiology of defaecation disorders including constipation, faecal incontinence and irritable bowel syndrome is also included, as well as considerations for further research in this field.

Normal values for high-resolution anorectal manometry in healthy young adults: evidence from Vietnam

BACKGROUND

High-resolution anorectal manometry (HRAM) has been developed to improve measurement of anorectal functions. This study aims to identify normal HRAM values in healthy young Vietnamese adults.

METHODS

We conducted a cross-sectional study at the National Hospital of Traditional Medicine (Hanoi, Vietnam) from July through December 2014. Healthy young adults were invited to participate in the study. All anorectal measurement values were performed using the ISOLAB high-resolution manometry system. Differences between groups were analyzed using Student's t-tests.

RESULTS

Thirty healthy young adults, including 15 males and 15 females aged 19-26 years, were recruited. Mean functional anal canal length was 3.4 ± 0.5 cm (range: 2.4-4.8 mm). Mean maximum resting pressure, mean maximum squeezing pressure, mean maximum coughing pressure, and mean maximum strain pressure were 65.5, 168.0, 125.9, and 84.2 mm Hg, respectively. All anal pressure values were significantly different between males and females. For rectal sensation measurements, only the volume at first sensation was significantly higher in males than in females.

CONCLUSIONS

This study provides normal HRAM value for healthy young adults in Vietnam. Sex may influence anal pressure and first rectal sensation values in this cohort. Further studies should be conducted in order to improve the quality of HRAM normal values and to confirm the effects of sex.

Spinal Cord Perfusion Pressure Correlates with Anal Sphincter Function in a Cohort of Patients with Acute, Severe Traumatic Spinal Cord Injuries

Background

Acute, severe traumatic spinal cord injury often causes fecal incontinence. Currently, there are no treatments to improve anal function after traumatic spinal cord injury. Our study aims to determine whether, after traumatic spinal cord injury, anal function can be improved by interventions in the neuro-intensive care unit to alter the spinal cord perfusion pressure at the injury site.

Methods

We recruited a cohort of patients with acute, severe traumatic spinal cord injuries (American Spinal Injury Association Impairment Scale grades A–C). They underwent surgical fixation within 72 h of the injury and insertion of an intrathecal pressure probe at the injury site to monitor intraspinal pressure and compute spinal cord perfusion pressure as mean arterial pressure minus intraspinal pressure. Injury-site monitoring was performed at the neuro-intensive care unit for up to a week after injury. During monitoring, anorectal manometry was also conducted over a range of spinal cord perfusion pressures.

Results

Data were collected from 14 patients with consecutive traumatic spinal cord injury aged 22–67 years. The mean resting anal pressure was 44 cmH₂O, which is considerably lower than the average for healthy patients, previously reported at 99 cmH₂O. Mean resting anal pressure versus spinal cord perfusion pressure had an inverted U-shaped relation (Ȓ² = 0.82), with the highest resting anal pressures being at a spinal cord perfusion pressure of approximately 100 mmHg. The recto-anal inhibitory reflex (transient relaxation of the internal anal sphincter during rectal distension), which is important for maintaining fecal continence, was present in 90% of attempts at high (90 mmHg) spinal cord perfusion pressure versus 70% of attempts at low (60 mmHg) spinal cord perfusion pressure (P < 0.05). During cough, the rise in anal pressure from baseline was 51 cmH₂O at high (86 mmHg) spinal cord perfusion pressure versus 37 cmH₂O at low (62 mmHg) spinal cord perfusion pressure (P < 0.0001). During anal squeeze, higher spinal cord perfusion pressure was associated with longer endurance time and spinal cord perfusion pressure of 70–90 mmHg was associated with stronger squeeze. There were no complications associated with anorectal manometry.

Conclusions

Our data indicate that spinal cord injury causes severe disruption of anal sphincter function. Several key components of anal continence (resting anal pressure, recto-anal inhibitory reflex, and anal pressure during cough and squeeze) markedly improve at higher spinal cord perfusion pressure. Maintaining too high of spinal cord perfusion pressure may worsen anal continence.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12028-021-01232-1.

Slow-transit constipation and criteria for colectomy: a cross-sectional study of 1568 patients

Background

Colectomy remains a treatment option for a minority of patients with slow-transit constipation (STC) refractory to conservative treatment. However careful patient selection is essential to maximize benefits and minimize risk of adverse outcome. This study determined the proportion of patients with chronic constipation that would meet criteria for colectomy based on recent European graded practice recommendations derived by expert consensus.

Methods

Retrospective application of graded practice recommendations was undertaken on a prospectively maintained data set of consecutive adult patients with chronic constipation who underwent whole-gut transit studies using radio-opaque markers. Primary analysis applied contraindications achieving high level of expert consensus (normal whole-gut transit as an absolute contraindication and faecal incontinence as a relative contraindication for colectomy). Secondary analysis applied contraindications with less certain consensus.

Results

Primary analysis of 1568 patients undergoing a whole-gut transit study between January 2004 and March 2016 found 208 (13.3 per cent) met published criteria to be selected for colectomy, with 974 excluded for normal whole-gut transit and 386 for faecal incontinence. Secondary analysis demonstrated high prevalence of other relative contraindications to colectomy: 165 concomitant upper gastrointestinal symptoms, 216 abdominal pain (including 126 irritable bowel syndrome), and 446 evacuation disorder. The majority of patients (416 of 594) had two or more relative contraindications. If these patients were excluded, only 26 (1.7 per cent) chronically constipated patients retrospectively met selection criteria for colectomy.

Conclusions

The retrospective application of selection criteria is a limitation. However, the data highlight the high prevalence of factors associated with poor postoperative outcome and provide further caution to surgeons undertaking colectomy for STC.

Anorectal Manometry on Children: A Moroccan Series and Literature Review

Introduction and objectives: Anorectal manometry is a test that evaluates the function of the rectum,but also the anus. It is useful for the diagnosis of several conditions like fecal incontinence and constipation.In children these tests are being increasingly used for all ages.The aim of this study was to determine the benefit of anorectal manometry in children and to report our experience. Material and Methods:Over a period of four years, 273children that underwent anorectal manometry were included in the study,their data and tests results were analyzed. Results:Out of 273 patients included,68,5% were boys and 31,5% were girls.The mean age was 9 years.154patients(51,6%) had Fecal incontinence(Group1),75children(27,5%) had chronic constipation(Group2),and both of them(Group3) were reported in 37children(13,6%).An awake manometry was  performed in 248children(91%) however this test under sedation allowed us the exclusion of Hirschsprung’s disease in 21children(84%).In group1, 25%patients had bad anal contraction.In groupe3, 21,6%children had bad anal contraction.The statistical analysis showed a significant difference in age(p=0.022) and resting pressure(p=0.050) between the three groups.Children with fecal incontinence had a higher rate of dyssynergy,80.2% and 83.8% in groups 1 and 3 respectively compared to 60.4% in patients with chronic constipation(p=0,852) Conclusion:The gold standard for the exploration of children’s terminal constipation and encopresis is the anorectal manometry.It is an important tool to establish diagnosis.In our study, this test allow the exclusion of Hirschsprung’s disease in infants with constipation,  in other hand we found a higher rate of dyssynergy in children with fecal incontinence(80%) which had allow us to propose a biofeedback therapy.

Anorectal manometry in pediatric settings: A systematic review of 227 studies

BACKGROUND

There is wide variation in the clinical use of diagnostic tools for children with chronic constipation and functional/structural fecal incontinence (CCFSFI). Anorectal manometry (ARM) is a well-recognized technique to assess the function of the anorectum.

PURPOSE

Our aim was to perform an up-to-date review on ARM in pediatric patients with CCFSFI, with specific focus on the indication of use and protocol. Variation of its use in pediatrics will be explored.

METHODS

A systematic search was conducted for empirical studies utilizing ARM with a pediatric sample. A keyword search of literature published in English before July 2018 was conducted and updated to October 2019. Data on demographics, clinical information, study aims, ARM parameters and use of sedation/anesthesia were collected.

KEY RESULTS

A total of 227 studies were included in this systematic review. The age of study participants at the time of ARM ranged from birth to 18 years. ARM was most commonly used in patients with organic conditions (65%) compared to functional constipation (41%). In almost half [108/227 (48%)] of the studies, ARM was performed awake. The ARM parameters most frequently assessed were the rectoanal inhibitory reflex, which was evaluated in 198/227 studies (87%) and the anal resting pressure [166/227 studies (73%)].

CONCLUSIONS AND INFERENCES

This systematic review has highlighted the vast variation of ARM use within pediatrics and the need to strive toward standardization and use of consensus guidelines. We anticipate this will further advance our understanding of the pathophysiological mechanisms involved in children with defecation disorders.

Systematic evaluation of cough-anorectal pressure responses in health and in fecal incontinence: A high-resolution anorectal manometry study

BACKGROUND

Anorectal manometry is the most commonly performed test of anorectal function. The cough-anorectal response is frequently assessed as part of a routine manometric investigation but has not previously been the subject of detailed analysis. This study systematically examined anorectal pressure responses to cough in health and evaluated the impact of parity and symptoms of fecal incontinence (FI) on measurements.

METHODS

High-resolution anorectal manometry (HR-ARM) traces from nulliparous (n = 25) and parous (n = 25) healthy volunteers (HV: aged 41, range 18-64), and 57 parous patients with FI (age 47, range 28-72) were retrospectively reviewed. Cough-anorectal pressure responses were analyzed between groups by qualitative and quantitative approaches.

KEY RESULTS

In health, traditional anal pressure measurements ("rest" and "squeeze") were similar between nulliparous and parous women. In contrast, incremental anal-rectal pressure difference during cough significantly differed: nulliparous 42 mm Hg (95% CI: 21-64) vs. parous 6 mm Hg (-14-25), P < 0.036). This measure also differed significantly between nulliparous HVs and patients with FI (-2 mm Hg (95% CI: -15-12), P < 0.001), but not between parous HVs and FI. Qualitatively, a color-contour trace resembling a "spear" in the upper anal canal was observed uniquely in FI. Of 25 patients with normal anal function by traditional measures, cough parameters were abnormal in 52%.

CONCLUSIONS AND INFERENCES

Novel HR-ARM measures during coughing revealed differences in anal function between nulliparous and parous HV, and patients with FI, which were not detected by traditional measures. Cough-anorectal measurements may improve manometric yield, though clinical utility would require assessment by longitudinal studies.

[Recommendations for the Protocol of functional examination of the anorectal zone and disorders classification: the International Anorectal Physiology Working Group consensus and Russian real-world practice]

This manuscript summarizes consensus reached by the International Anorectal Physiology Working Group (IAPWG) for the performance, terminology used, and interpretation of anorectal function testing including anorectal manometry (focused on high-resolution manometry), the rectal sensory test, and the balloon expulsion test. Based on these measurements, a classification system for disorders of anorectal function is proposed. Aim to provide information about methods of diagnosis and new classification of functional anorectal disorders to a wide range of specialists general practitioners, therapists, gastroenterologists, coloproctologists all who face the manifestations of these diseases in everyday practice and determine the diagnostic and therapeutic algorithm. Current paper provides agreed statements of IAPWG Consensus and comments (in italics) of Russian experts on real-world practice, mainly on methodology of examination. These comments in no way intended to detract from the provisions agreed by the international group of experts. We hope that these comments will help to improve the quality of examination based on the systematization of local experience with the use of the methods discussed and the results obtained. Key recommendations: the International Anorectal Physiology Working Group protocol for the performance of anorectal function testing recommends a standardized sequence of maneuvers to test rectoanal reflexes, anal tone and contractility, rectoanal coordination, and rectal sensation. Major findings not seen in healthy controls defined by the classification are as follows: rectoanal areflexia, anal hypotension and hypocontractility, rectal hyposensitivity, and hypersensitivity. Minor and inconclusive findings that can be present in health and require additional information prior to diagnosis include anal hypertension and dyssynergia.

Initial experience with SphinKeeper™ intersphincteric implants for faecal incontinence in the UK: a two-centre retrospective clinical audit

AIM

The SphinKeeper™ artificial bowel sphincter implant is a relatively new surgical technique for the treatment of refractory faecal incontinence. This study presents the first experience in two UK tertiary centres.

METHOD

This is a retrospective audit of prospectively collected clinical data in relation to technique, safety, feasibility and short-term effectiveness from patients undergoing surgery from January 2016 to April 2019. Baseline data, intra-operative and postoperative complications, symptoms [using St Mark's incontinence score (SMIS)] and radiological outcomes were analysed.

RESULTS

Twenty-seven patients [18 women, median age 57 years (range 27-87)] underwent SphinKeeper. In 30% of the patients, the firing device jammed and not all prostheses were delivered. There were no intra-operative complications and all patients were discharged the same or the following day. SMIS significantly improved from baseline [median -6 points (range -12 to +3); P < 0.00016] with 14/27 (51.9%) patients achieving a 50% reduction in the SMIS score. On postoperative imaging, a median of seven prostheses (range 0-10) were identified with a median of five (range 0-10) optimally placed. There was no relationship between number of well-sited prostheses on postoperative imaging and categorical success based on 50% reduction in SMIS (χ² test, P = 0.79).

CONCLUSION

SphinKeeper appears to be a safe procedure for faecal incontinence. Overall, about 50% patients achieved a meaningful improvement in symptoms. However, clinical benefit was unrelated to the rate of misplaced/migrated implants. This has implications for confidence in proof of mechanism and also the need for technical refinement.

The relationships between the results of contemporary tests of anorectal structure and sensorimotor function and the severity of fecal incontinence

BACKGROUND

Diagnostic investigations for fecal incontinence (FI) assess the structure and sensorimotor function of the anorectum. Investigations include anorectal manometry, anorectal sensory testing, pudendal nerve terminal motor latencies (PNTML), and endoanal sonography. The severity of FI and results of investigations are often discordant and the rate of symptom resolution following treatment remains <40%. High-resolution anorectal manometry (HRAM) and three-dimensional endoanal ultrasound (3D-US) have been introduced during the last decade. This study aims to assess the strength of relationships between contemporary investigation results and FI severity.

METHODS

Adults presenting for investigation of FI were assessed using the St Mark's FI severity score (SMIS), HRAM, anorectal sensory testing, PNTML, and 3D-US.

KEY RESULTS

246 patients were included. There were significant relationships between the SMIS and HRAM (resting pressure r_s = -0.23, 95% CI = (-0.34, -0.11), P < .001; squeeze pressure (r_s  = -0.26, 95% CI = (-0.37, -0.14), P < .001) and 3D-US (anterior EAS length r_s = -0.22, 95% CI = (-0.34, -0.09), P = .001). The relationships between SMIS and HRAM had a greater effect size in those with urge-predominant symptoms (resting pressure: r_s = -0.40, 95% CI = (-0.57, -0.20), P < .001, squeeze pressure: r_s = -0.34, 95% CI = (-0.52, -0.12), P = .003). Overall, the variance in SMIS accounted for by anorectal investigations was 8.6% (R² = 0.098, adjusted R² = 0.086, P < .001).

CONCLUSIONS AND INFERENCES

Anorectal investigations are not strong predictors of FI severity. These findings may reflect the multifactorial, heterogeneous pathophysiology of FI, the limitations of the SMIS and anorectal investigations, and contributing factors extrinsic to the anorectum.

Comparison of anorectal function measured using wearable digital manometry and a high resolution manometry system

There is a need for a lower cost manometry system for assessing anorectal function in primary and secondary care settings. We developed an index finger-based system (termed "digital manometry") and tested it in healthy volunteers, patients with chronic constipation, and fecal incontinence. Anorectal pressures were measured in 16 participants with the digital manometry system and a 23-channel high-resolution anorectal manometry system. The results were compared using a Bland-Altman analysis at rest as well as during maximum squeeze and simulated defecation maneuvers. Myoelectric activity of the puborectalis muscle was also quantified simultaneously using the digital manometry system. The limits of agreement between the two methods were -7.1 ± 25.7 mmHg for anal sphincter resting pressure, 0.4 ± 23.0 mmHg for the anal sphincter pressure change during simulated defecation, -37.6 ± 50.9 mmHg for rectal pressure changes during simulated defecation, and -20.6 ± 172.6 mmHg for anal sphincter pressure during the maximum squeeze maneuver. The change in the puborectalis myoelectric activity was proportional to the anal sphincter pressure increment during a maximum squeeze maneuver (slope = 0.6, R2 = 0.4). Digital manometry provided a similar evaluation of anorectal pressures and puborectalis myoelectric activity at an order of magnitude less cost than high-resolution manometry, and with a similar level of patient comfort. Digital Manometry provides a simple, inexpensive, point of service means of assessing anorectal function in patients with chronic constipation and fecal incontinence.

The London Classification: Improving Characterization and Classification of Anorectal Function with Anorectal Manometry

PURPOSE OF REVIEW

Objective measurement of anorectal sensorimotor function is a requisite component in the clinical evaluation of patients with intractable symptoms of anorectal dysfunction. Regrettably, the utility of the most established and widely employed investigations for such measurement (anorectal manometry (ARM), rectal sensory testing and the balloon expulsion test) has been limited by wide variations in clinical practice.

RECENT FINDINGS

This article summarizes the recently published International Anorectal Physiology Working Group (IAPWG) consensus and London Classification of anorectal disorders, together with relevant allied literature, to provide guidance on the indications for, equipment, protocol, measurement definitions and results interpretation for ARM, rectal sensory testing and the balloon expulsion test. The London Classification is a standardized method and nomenclature for description of alterations in anorectal motor and sensory function using office-based investigations, adoption of which should bring much needed harmonization of practice.

[Interdisciplinary consensus on Russian-language terminology of anorectal sphincterometry and profilometry]

Aim to describe the results of a multidisciplinary discussion on the terminology of anorectal sphincterometry (AS) and profilometry (AP). We performed online survey with the use of public platform Google forms to harmonize Russian terms to be used to describe the results of AP and AS and their abbreviations. The invitation to participate in the survey was sent to the authors who use the results of AP and AS in clinical practice and perform the diagnostic procedures. The obtained answers were analyzed with the use of the aggregator and Statistica 10 (StatSoft Inc, USA) software. The level of consensus was analyzed with the use of modified Delphi criteria (C1 agreement of 90% of participants, C2 agreement of 75 to 90%, C3 less than 75%). Invitations sent 76, responses obtained 63 (response rate 82.9%). Consensus level 1 was reached for all the terms of AP and for 4out of 7 terms to describe the results of AS (3 out of 7 terms were of moderate agreement, C2). The need for the use of predefined abbreviations of terms for AS and AP was of a low rate of consensus (71.4%). The agreed terms of AS and AP should be used to prepare a conclusion for the diagnostic procedures and to publish scientific reports.

Assessing Anorectal Function in Constipation and Fecal Incontinence

Constipation and fecal incontinence are commonly encountered complaints in the gastrointestinal clinic. Assessment of anorectal function includes comprehensive history, rectal examination, and prospective stool diary or electronic App diary that accurately captures bowel symptoms, evaluation of severity, and quality of life of measure. Evaluation of a suspected patient with dyssynergic constipation includes anorectal manometry, balloon expulsion test, and defecography. Investigation of a suspected patient with fecal incontinence includes high-resolution anorectal manometry; anal ultrasound or MRI; and neurophysiology tests, such as translumbosacral anorectal magnetic stimulation or pudendal nerve latency. This article provides an approach to the assessment of anorectal function.

Anorectal manometry in children with defecation disorders BSPGHAN Motility Working Group consensus statement

Defecatory disorders in children, including chronic constipation (CC) and fecal incontinence (FI), are common conditions worldwide and have a significant impact on children, their families, and the healthcare system. Anorectal manometry (ARM) and high-resolution anorectal manometry (HRAM) are relatively novel tools for the assessment of anal sphincter function and rectal sensation and have contributed significantly to improving the understanding of the anorectum as a functional unit. ARM has been recognized as the investigation of choice for adults with symptoms of defecation disorders, including fecal incontinence (FI), evacuation difficulties, and constipation. Although it is the gold standard tool in adults, it has yet to be formally accepted as a standardized diagnostic tool in the pediatric age, with limited knowledge regarding indications, protocol, and normal values. ARM/HRAM is slowly becoming recognized among pediatricians, but given that there are currently no agreed guidelines there is a risk that will lead to diversity in practice. The British Society of Paediatric Gastroenterology, Hepatology and Nutrition (BSPGHAN)-Motility Working Group (MWG) therefore has taken the opportunity to provide guidance on the use of ARM/HRAM in children with CC and/or FI.

High resolution anorectal manometry. Recommendations on russian-language terminology based on interdisciplinary consensus

The aim of the paper — is to present the results of the consensus on the terminology used to describe data of high-resolution anorectal manometry.

Methods: Online survey was conducted with the help of the public platform “Google forms” with the aim to harmonize the terms, which are used to conduct high-resolution anorectal manometry (HRAM), to agree the conformity of the proposed Russian-language terms to those used in English-language literature, and their abbreviations.

Results: According to the aim, 56 specialists of different medical specialties who perform and use the results of HRAM in clinical practice and research were invited to participate in the survey. We received 45 answers from the respondents (42.2% coloproctologists, 22.2% gastroenterologists, 15.6% surgeons, 20% — representatives of other specialties). The response rate was 80.3%. According to the survey, 95.6% of respondents supported the need for harmonization of terms. Ten out of the 11 terms reached consensus level C1 (excellent), 1 term level of consistency was C2 (moderate). 90.9% of respondents (consensus level C1) were in favor of the appropriateness of using common abbreviations. However, the proposed abbreviations of the terms used in the conduct and description of the results of the HRAM can be accepted with reservations (in 10 cases out of 11 consensus level was C2).

Conclusions: The agreed in interdisciplinary consensus terms can be approved and recommended for the use in clinical practice and when research data are published in Russian-language scientific literature.

Scientific solution to a complex problem: physiology and multidisciplinary team improve understanding and outcome in chronic constipation and faecal incontinence

PURPOSE

There is a lack of diagnostic credibility to direct focused management for children with chronic constipation (CC) and faecal incontinence (FI). The aim is to assess the impact of an innovative Children's Anorectal Physiology Service (CAPS) focusing on improving outcomes in children with CC/FI.

METHODS

Prospective data: demographics, bowel and quality of life (QoL)/risk of distress questionnaires. Diagnostics: awake high-resolution anorectal manometry (AHRAM), endoanal ultrasound and transit marker studies (TMS).

RESULTS

Total patients: 112; 66 males (59%); median 9 years (17 months to 16 years). Patient groups included: 89 (79%) had functional CC/FI; 9 (8%), Hirschsprung's disease; 12 (11%), anorectal malformations and 2 (2%), trauma. St Marks Incontinence score (SMIS) abnormal in 91 (81%) and Cleveland Constipation Score (CCS) in 101 (90%) patients. Anorectal manometry: 94 (84%) awake and 18 (17%) under anaesthesia. Play specialist input 37 (33%) patients. AHRAM abnormal 65 (58%): sphincter dysfunction 36 (32%) and altered rectal sensation: hyposensitive 22% (20/91); 21% (19/91) hypersensitive. TMS normal in 64 (57%), 17 (15%) slow transit and 27 (24%) rectal evacuatory disorder. Risk of distress in 38% and poor QoL in 55% patients which correlated with abnormal SMIS (p = 0.02). Patient/parent satisfaction improved significantly (p < 0.05).

CONCLUSIONS

Scientific investigations combined with multidisciplinary team improve patient satisfaction and reduces patient self-report illness severity. A complex problem requires a scientific solution.

Effect of gender on the etiology of fecal incontinence: Retrospective analysis of a tertiary referral center in Turkey

BACKGROUND/AIMS

Anorectal diseases, including fecal incontinence, are prevalent and have an enormous impact on the quality of life. Therefore, investigating their etiological factors may help to reduce the incidence and/or the severity of the underlying diseases.

MATERIALS AND METHODS

Referral complaints (constipation, strained defecation, and incontinence) and medical and anorectal manometry records of 883 (562 female/321 male, ages 45.17±1.00 and 48.41±0.63 years, respectively) patients were evaluated retrospectively. Maximal resting pressure (MRP) and maximal squeeze pressure (MSP) measured by stationary pull-through technique, volume of rectoanal inhibitory reflex, and sensory threshold to rectal balloon distention (ST) were obtained by water perfusion system. Data were compared according to referral complaints, age, gender, parity, and underlying diseases.

RESULTS

Incontinence was the most frequent referral complaint in 61.2% of females and 67.6% of males. MRP and MSP were significantly lower in incontinent females than in the other groups. In incontinent males, MSP was lower than the strained defecation group, and ST was higher than the constipation group. Age was negatively correlated with MRP for both of the genders and in all groups. Obstetric trauma (85%) and number of parity (3.40±2.59) were significantly higher in incontinent females. Moreover, the most prevalent underlying disease was diabetes in incontinent females (13.7%) and neurological diseases, including traumas, in incontinent males (41.5%).

CONCLUSION

Increasing awareness of labor safety, controlling diabetes mellitus, and preventing obstetric traumas may reduce the prevalence of fecal incontinence.

Colonic transit, high-resolution anorectal manometry and MRI defecography study of constipation in Parkinson's disease

INTRODUCTION

Despite clinical relevance and potential role on the disease pathogenesis, underlying mechanisms of constipation in Parkinson's disease (PD) remain poorly understood. A systematic assessment using complementary physiological investigations was performed to elucidate constipation pathophysiology in order to improve its symptomatic management.

METHODS

PD patients with constipation were evaluated with clinical questionnaires, colonic transit, high-resolution anorectal manometry and MRI defecography. Results were compared and correlated with clinical features.

RESULTS

A total of 42 patients (69% male; age 68 ± 8 years; disease duration 10.5 ± 6.1 years) were included, of whom 33 (78.6%) had objective constipation defined by < 3 bowel movements per week or straining. Severity of constipation measured by self-administered questionnaires correlated with disease severity, burden of motor and non-motor symptoms but not with age, disease duration or Parkinson's medications. Colonic transit and anorectal function (high-resolution anorectal manometry and/or MRI defecography) was assessed in 15 patients. A combination of both delayed colonic transit and anorectal dysfunction was the pattern most commonly found (60% of patients) and overall anorectal dysfunction was more prevalent than isolated slow transit constipation. Physiological findings were heterogeneous including reduced colonic motility, rectal hyposensitivity, defecatory dyssynergia and poor motor rectal function.

CONCLUSION

Subjective constipation in PD is poorly correlated with commonly used definition, assessment questionnaires and physiological results. Multiple complex overlapping pathophysiological mechanisms are responsible including slow transit and anorectal dysfunction. Complementary investigations to assess colonic transit and anorectal function are required in those with refractory symptoms for a systematic assessment and appropriate symptomatic management.

High-resolution anal manometry: Repeatability, validation, and comparison with conventional manometry

BACKGROUND

Accurate measurement of anal sphincter function is potentially of value in defining treatment of common pelvic floor disorders. The aim of this study was to establish repeatability and validate high-resolution anorectal manometry (HRAM) by comparison to conventional manometry (CM). Arising from this work would be definitive normal range data.

METHODS

Eighty healthy volunteers (40 female) underwent a test-retest repeatability study. A 16-channel water-perfused HRAM catheter was compared to an 8-channel conventional catheter using a station pull-through technique.

KEY RESULTS

High-resolution anorectal manometry had similar precision to conventional manometry when measuring resting pressure (intraclass correlation coefficient [ICC] 0.73 vs 0.68, HRAM vs CM) and squeeze increment (ICC 0.90 vs 0.94, HRAM vs CM). HRAM measured resting pressures 10% lower than CM and squeeze pressure 27% higher than CM.

CONCLUSIONS AND INFERENCES

High-resolution anorectal manometry is a valid technique with comparable precision to CM. HRAM measurements differ considerably to CM, and a new set of normal values must be used.

High-resolution Anorectal Manometry in the Diagnosis of Functional Defecation Disorder in Patients With Functional Constipation: A Retrospective Cohort Study

Background/Aims

High-resolution anorectal manometry (HRAM) has been considered a first-line diagnostic tool for functional defecation disorder. However, clinical studies on HRAM used in constipation patients are very limited and few studies have reported the characteristics of anorectal pressure in Chinese patients. The aim of this study is to investigate the characteristics of motility data in a cohort of Chinese patients with functional constipation.

Methods

A total of 82 consecutive patients with functional constipation who underwent a standardized HRAM were retrospectively enrolled in this study. The functional defecation disorder was classified into Rao’s types.

Results

The mean age of 82 patients was 51 years (range, 16–83 years). Indications for anorectal manometry were functional constipation for all patients. The mean resting pressure was 69.2 ± 21.2 mmHg (range, 24.5–126.9 mmHg). The mean maximum squeezing pressure was 198.4 ± 75.6 mmHg (range, 54.2–476.9 mmHg). The mean length of the anal high pressure zone was 3.4 ± 1.0 cm (range, 0.6–4.9 cm). Sixty (73.2%) patients were diagnosed as functional defecation disorder. In attempted defecation, type I was most common (n = 24), followed by type II (n = 12), type III (n = 11), and type IV (n = 13) that were present on HRAM according to Rao’s classification. In all 60 patients with functional defecation disorder, 37 were women and 23 were men. Men were significantly more likely than women to have functional defecation disorder (92.0% vs 64.9%, P = 0.014).

Conclusion

HRAM could be used as a test for the diagnosis of functional defecation disorder and functional defecation disorder is common in Chinese patients with functional constipation.

Anorectal physiology in health: A randomized trial to determine the optimum catheter for the balloon expulsion test

BACKGROUND

Anorectal manometry (ARM) and balloon expulsion test (BET) are pivotal in investigation of anorectal disorders. There is controversy, however, about normal values and optimum methodology for performing these tests. Our aims were to compare BET using three different balloons and to establish normal values for ARM and BET in health.

METHODS

Forty-four female healthy subjects (mean age 56 ± 12 years) underwent ARM, followed by BET which was performed in a private toilet using three different catheters (party balloon, Foley catheter and a commercially available catheter) in a single-blinded randomized order. Outcome measures were time to balloon expulsion and comprehensive measures of anal sphincter function, the push maneuver and rectal sensation.

KEY RESULTS

The Foley catheter took longer to expel compared to both party and commercial balloons (both pairwise P < 0.001) with a wider distribution of results (P < 0.001). Ten of 40 healthy subjects could not expel the Foley catheter within 120 seconds. On ARM, older age was associated with lower resting anal sphincter pressure (ρ = -0.3, P = 0.05) and lower anal squeeze pressure (ρ = -0.3, P = 0.05). Having at least one vaginal delivery (compared to none) was associated with lower anal squeeze pressures (P = 0.03) and a smaller difference between cough and squeeze pressures (P = 0.03).

CONCLUSIONS & INFERENCES

A commercial balloon exhibited superior results in vivo compared to the Foley catheter without the concerns of latex allergy and quality control present with the use of a party balloon. Normal values for high-resolution water-perfused manometry have been established and an effect seen for age and parity.

Functional anal canal length measurement using high-resolution anorectal manometry to investigate anal sphincter dysfunction in patients with fecal incontinence or constipation

BACKGROUND

Using high-resolution anorectal manometry, we aimed to evaluate the: (a) optimal threshold to measure functional anal canal length (FACL) with intra- and inter-observer variability; (b) relationship between abnormal FACL and other phenotypic findings; and (c) utility of FACL measurement to discriminate between healthy volunteers (HV) and patients with fecal incontinence (FI) or chronic constipation (CC).

METHODS

Consecutive patients referred for investigation of FI or CC in isolation were included. FACL was calculated at 5, 10, 20, 30, and 50 mm Hg above rectal pressure. 5th-95th percentile in HV defined limits of normality.

KEY RESULTS

FACL was analyzed in 192 patients with FI (154 females), 204 patients with CC (175 females), and 134 HV (101 females). The optimal threshold for measurement of FACL was 20 mm Hg. Using this threshold, observer reproducibility was very high (ICC 0.99, P < 0.0001). FACL was shorter in females with FI and longer in females with CC compared to HV (2.3 vs 2.9 cm; and 3.4 cm vs 2.9 cm; both P < 0.0001). Twenty percent of females and 13% males with FI had a short FACL, associated with older age, anal hypotonia or hypocontractility, and a atrophic internal anal sphincter. However, abnormal FACL in isolation was only found in 1/190 FI (0.5%) and 2/201 CC (1%) patients; all other patients had other abnormal manometric findings.

CONCLUSIONS AND INFERENCES

Considering overlap with other routinely evaluated manometric parameters, FACL measurement does not provide additional information in the diagnostic assessment of FI or CC.