Expert consensus document: Advances in the evaluation of anorectal function

Dynamic functional luminal imaging probe analysis of the anal sphincter opening function during straining in healthy volunteers

The objective of the present study was to introduce a novel method of assessing anal canal opening in healthy volunteers (HV) using the EndoFLIP system. By analyzing dynamic loops during push maneuvers, the study aimed to identify the most reliable markers of anal canal opening function during this maneuver. Forty HV women were recruited and underwent anal canal assessments with the EndoFLIP system, both at rest and during push maneuvers. Cross-sectional area (CSA)-pressure loops were constructed for each HV at distension volumes of 40 mL and 50 mL. Key parameters (pressure and CSA) derived from these loops were identified as potential markers of anal function to reduce dimensionality. Anal opening function during push maneuver was quantified in both percentage (relative variation) and absolute (absolute variation) values for pressure and CSA. The direction of the CSA-pressure loops during the push maneuver at 40 mL and 50 mL of distension was upward and to the right, indicating an increase in both pressure and CSA during straining. None of the demographic data were significant predictors of any characteristics of the CSA-pressure loops at 40 mL and 50 mL of distension. The mean relative variation in pressure and CSA at 50 mL of distension and, to a lesser extent, the maximal relative variation pressure and CSA, were identified as markers with the lowest variability. This pilot study points to potential markers for assessing anal opening function during push maneuvers. Further confirmatory studies are necessary to establish the clinical utility of these markers.NEW & NOTEWORTHY In the present study, we generated a bioinformatics pipeline for analyzing anal EndoFLIP data in healthy volunteers using automated data reprocessing to identify potential markers of anal opening function during the push maneuver. Mean relative variations in pressure and CSA at 50 mL of distension were identified as the most indicative parameters. Given that this was a pilot study, our findings warrant further confirmatory research to establish the clinical relevance of these markers.

Prevalence and Clinical Impact of the London Classification: A Prospective, International, Multicenter Study From the Lower Gastrointestinal International Consortium (LoGIC)

INTRODUCTION

The London classification provides standardization for characterization of disorders of anorectal function, although prevalences and clinical impact of these disorders are unclear.

METHODS

An international research consortium was established, including 5 specialist centers. Prospective data were collected in consecutive adults referred for refractory chronic constipation (CC), fecal incontinence (FI), or coexistent CC/FI over 18 months. Patients completed a standardized clinical questionnaire and underwent anorectal physiology tests, which were performed and interpreted using uniform methodology. The prevalence of the London classification was compared between symptom groups (CC, FI, and coexistent CC/FI), equipment types, and sites. Clinical impact was assessed using Cleveland Clinic Constipation and St. Marks Incontinence Scores.

RESULTS

Of 1,012 included patients (85.6% women), 30.5% had self-reported CC, 33.2% had FI, and 36.3% had coexistent CC/FI. Rectoanal areflexia was uncommon (3.1%). Disorders of anal tone/contractility (CC: 45.0%; FI: 68.5%; coexistent CC/FI: 63.8%; P < 0.0001) and disorders of rectal sensation (major findings: rectal hyposensitivity, CC: 10.0%; FI: 5.0%; coexistent CC/FI: 11.1%; P = 0.018; rectal hypersensitivity, CC: 3.8%; FI: 9.0%; coexistent CC/FI: 4.9%; P = 0.025) varied between the symptom groups and were associated with symptom severity. Most disorders of rectoanal coordination were found in similar proportions across the symptom groups and were not associated with the severity of CC (median Cleveland Clinic Constipation Score 10-14 in all groups). Prevalences of some disorders differed between equipment types (specifically balloon expulsion test).

DISCUSSION

This prospective multicenter study provides information on the prevalence and clinical impact of the London classification and will guide refinement of the current London classification.

Characterization of obstructive defecation from a structural and a functional perspective

BACKGROUND/AIMS

Defecation disorders can occur as a consequence of functional or structural anorectal dysfunctions during voiding. The aims of this study is to assess the prevalence of structural (SDD) vs functional (FDD) defecation disorders among patients with clinical complaints of obstructive defecation (OD) and their relationship with patients' expulsive capacity.

PATIENTS AND METHODS

Retrospective study of 588 patients with OD studied between 2012 and 2020 with evacuation defecography (ED), and anorectal manometry (ARM) in a subgroup of 294.

RESULTS

90.3% patients were women, age was 58.5±12.4 years. Most (83.7%) had SDD (43.7% rectocele, 45.3% prolapse, 19.3% enterocele, and 8.5% megarectum), all SDD being more prevalent in women except for megarectum. Functional assessments showed: (a) absence of rectification of anorectal angle in 51% of patients and poor pelvic descent in 31.6% at ED and (b) dyssynergic defecation in 89.9%, hypertonic IAS in 44%, and 33.3% rectal hyposensitivity, at ARM. Overall, 46.4% of patients were categorized as pure SDD, 37.3% a combination of SDD+FDD, and 16.3% as having pure FDD. Rectal emptying was impaired in 66.2% of SDD, 71.3% of FDD and in 78% of patients with both (p=0.017).

CONCLUSIONS

There was a high prevalence of SDD in middle-aged women with complaints of OD. Incomplete rectal emptying was more prevalent in FDD than in SDD although FDD and SDD frequently coexist. We recommend a stepwise therapeutic approach always starting with therapy directed to improve FDD and relaxation of striated pelvic floor muscles.

Correlation of Digital Rectal Examination and Anorectal Manometry with Patient-Reported Outcomes Among Women with Fecal Incontinence

INTRODUCTION AND HYPOTHESIS

Standardized digital rectal examination (DRE) correlates with anorectal manometry (ARM) measures. However, less is known about the relationship between DRE/ARM measures and patient-reported outcomes (PROs), especially among women with fecal incontinence (FI). Our aims were to evaluate associations between DRE and ARM measures and compare PROs with diagnostic evaluation measures for women with FI.

METHODS

We analyzed data from the parent clinical trial, Controlling Anal incontinence by Performing Anal exercises with Biofeedback or Loperamide (CAPABLe). We pooled data from randomized women who completed standardized ARM, DRE, and validated PROs at baseline and 12 and 24 weeks post-treatment initiation. PROs included FI severity, impact on quality of life, and bowel diary data. We analyzed ARM pressure and volume data and DRE using the Digital Rectal Examination Scoring System (DRESS) resting and squeeze mean scores. We used Spearman Rank Correlation to measure associations between the ARM measures and mean DRESS scores, and between PROs and ARM/DRESS scores.

RESULTS

Among 291 randomized women with ARM and DRE data, the correlation between DRESS and ARM resting measures was 0.196 (p<0.001) and between squeeze measures was 0.247 (p<0.001). At most timepoints, PROs more consistently correlated with squeeze ARM pressures and squeeze DRESS scores than resting measures.

CONCLUSIONS

We found weak correlations between ARM and DRE measures and between those measures and PROs. Although DRE and ARM are commonly used diagnostic measures among women with FI, the weak correlations with patient-reported symptoms raises questions about their utility in clinical care.

Novel Concepts on the Functional Neuroanatomy of the Anorectum: Implications for Anorectal Neuropathy and Neuromodulation Therapy

Anorectal neuropathy causes anorectal dysfunction, yet it is poorly recognized. This stems from both a lack of understanding of the extrinsic and intrinsic innervation of the anorectum and tools for evaluation of neuronal function. Our objective was to provide an improved understanding of the neuronal networks of the anorectum and discuss its functional significance. We performed a comprehensive and up-to-date review of the published literature on anorectal neuroanatomy to generate our findings. Anorectal nerve innervation appears to be much more complex than hitherto known with an extensive overlap, intercommunications, and variations. The innervations arise from 5 sources as evidenced by immunohistochemical markers: Sympathetic innervation arises from the superior hypogastric plexus, hypogastric plexus, and splanchnic nerves (T1-L2); the parasympathetic from pelvic splanchnic nerves (S1-S4); the mixed autonomic from inferior hypogastric plexus; the somatic from pudendal nerves; and the intercommunicating nerves. Furthermore, they are fine, closely packed nerves susceptible to damage from obstetric or spinal cord injury, or pelvic surgery that may not manifest with bowel problems immediately but later in life. This illustrated review provides a new understanding of the afferent and efferent pathways between the rectum, spinal cord, and brain, and a framework for clinical implications of anorectal neuropathy, such as anal sphincter or rectal sensory or rectal accommodation dysfunction, causing bowel problems. Insights into the functional neuroanatomy provide an improved mechanistic understanding of anorectal symptoms and could facilitate the development of neurophysiological tests such as translumbosacral anorectal magnetic stimulation and neuromodulation treatments such as sacral neuromodulation and translumbosacral neuromodulation treatment.

Prevalence and Factors associated with Bowel Dysfunctions after Pull-Through Surgery in Children Diagnosed with Hirschsprung Disease

Purpose

This study investigated the prevalence of bowel dysfunction and associated factors after pull-through surgery.

Methods

The medical records of children under 18 years old diagnosed with Hirschsprung disease (HD) based on histopathology between 2004 and 2022 were reviewed. Bowel dysfunction after pull-through surgery was categorized into Hirschsprung-associated enterocolitis (HAEC), constipation, and fecal incontinence.

Results

Among 97 children diagnosed with HD, the median age at presentation was 3 (2-15) days (84.54% male). The clinical manifestations included abdominal distension (58.76%), constipation (17.52%), bilious vomiting (17.52%), nonbilious vomiting (14.43%), and enterocolitis (12.37%). HDs were classified by the location of aganglionosis: short segments (74.23%), long segments (8.25%), total colonic (12.37%), and small intestinal (5.15%). Excluding surgical complications, the prevalence of bowel dysfunction was 64.95% during an average follow-up of 8.33 years. HAEC was the most common issue (46.39%), followed by nonretentive incontinence (22.68%), constipation (20.62%), and retentive incontinence (15.46%). Preoperative HAEC was significantly associated with post-surgery HAEC (adjusted odds ratio [aOR] 18.31; 95% confidence interval [CI], 1.30-257.73; p=0.031). The Duhamel operation was associated with constipation and retentive incontinence (aOR 62.15; 95% CI, 1.64-2,349.13; p=0.026). Age under 6 months at pull-through surgery was associated with nonretentive fecal incontinence after 4 years (aOR 8.83; 95% CI, 1.11-70.39; p=0.040).

Conclusion

The prevalence of bowel dysfunction in children with HD remains high despite successful surgical correction. Preoperative HAEC, Duhamel operation, and pull-through surgery before the age of 6 months were found to be independent factors associated with bowel dysfunction after pull-through surgery.

Irritable bowel syndrome: When food is a pain in the gut

Irritable bowel syndrome (IBS) is a chronic gastrointestinal condition associated with altered bowel habits and recurrent abdominal pain, often triggered by food intake. Current treatments focus on improving stool pattern, but effective treatments for pain in IBS are still lacking due to our limited understanding of pathophysiological mechanisms. Visceral hypersensitivity (VHS), or abnormal visceral pain perception, underlies abdominal pain development in IBS, and mast cell activation has been shown to play an important role in the development of VHS. Our work recently revealed that abdominal pain in response to food intake is induced by the sensitization of colonic pain-sensing neurons by histamine produced by activated mast cells following a local IgE response to food. In this review, we summarize the current knowledge on abdominal pain and VHS pathophysiology in IBS, we outline the work leading to the discovery of the role of histamine in abdominal pain, and we introduce antihistamines as a novel treatment option to manage chronic abdominal pain in patients with IBS.

Review article: advances in the diagnosis and management of anorectal motility disorders

BACKGROUND

Anorectal motility disorders such as dyssynergic defecation (DD), faecal incontinence (FI) and anorectal pain affect 40% of the population and are a frequent reason for gastroenterology consultation. They significantly affect the quality of life and lead to psychological distress. Lack of understanding of these problems compounded by a lack of availability and knowledge of diagnostic tools in most medical centres and/or trained physicians has significantly hampered this field.

AIMS

To discuss the latest advances in pathophysiology, diagnostic tests and therapeutic options for these disorders using an evidence-based approach.

METHODS

We reviewed the published literature over the past 20 years on DD, FI and anorectal pain and distilled these into a narrative review.

RESULTS

A detailed history, prospective stool diary and digital rectal exam, together with diagnostic tests such as anorectal manometry, balloon expulsion test, translumbosacral anorectal magnetic stimulation test for assessing neuropathy, defecography and anal ultrasound, can provide detailed mechanistic and structural information. Such knowledge can pave the way for a meaningful and pathophysiologic-based management approach. This could include biofeedback therapy for DD or FI, sensory training for rectal hyposensitivity or sensory adaptation training for rectal hypersensitivity or sphincter bulking agents or neuromodulation therapies. These treatments are effective and safe.

CONCLUSIONS

Anorectal motility disorders are common, but either less well recognized or poorly managed by most gastroenterologists. Equipped with the practical and up-to-date knowledge provided in this review, physicians could provide improved health care for these patients.

Use of a footstool improves rectal balloon expulsion in some patients with defecatory disorders

BACKGROUND

Whether patients with defecatory disorders (DDs) with favorable response to a footstool have distinctive anorectal pressure characteristics is unknown. We aimed to identify the clinical phenotype and anorectal pressure profile of patients with DDs who benefit from a footstool.

METHODS

This is a retrospective review of patients with high resolution anorectal manometry (HR-ARM) and balloon expulsion test (BET) from a tertiary referral center. BET was repeated with a 7-inch-high footstool in those who failed it after 120 s. Data were compared among groups with respect to BET results.

KEY RESULTS

Of the 667 patients with DDs, a total of 251 (38%) had failed BET. A footstool corrected BET in 41 (16%) of those with failed BET. Gender-specific differences were noted in anorectal pressures, among patients with and without normal BET, revealing gender-based nuances in pathophysiology of DDs. Comparing patients who passed BET with footstool with those who did not, the presence of optimal stool consistency, with reduced instances of loose stools and decreased reliance on laxatives were significant. Additionally, in women who benefited from a footstool, lower anal pressures at rest and simulated defecation were observed. Independent factors associated with a successful BET with a footstool in women included age <50, Bristol 3 or 4 stool consistency, lower anal resting pressure and higher rectoanal pressure gradient.

CONCLUSION & INFERENCES

Identification of distinctive clinical and anorectal phenotype of patients who benefited from a footstool could provide insight into the factors influencing the efficacy of footstool utilization and allow for an individualized treatment approach in patients with DDs.

Constipated patients with functional defecatory disorder have secondary rectal hyposensitivity due to altered rectal biomechanics

BACKGROUND AND AIM

Rectal hyposensitivity (RH) is common in constipation and often coexists with functional defecatory disorder (FDD). Rectal sensory thresholds are routinely evaluated with the anorectal manometry probe; however, the gold standard for the assessment of rectal sensitivity is with a barostat, use of which is limited by time constraints and availability. A novel rapid barostat bag (RBB) may facilitate measurements of rectal sensitivity. The aim is to evaluate the relationship between RH (measured by the RBB) and FDD (defined as any minor disorder of rectoanal coordination by the London classification) in constipated patients.

METHODS

Consecutive constipated patients referred for anorectal function testing underwent anorectal manometry with the 3D-HDAM probe as well as rectal sensation testing with the RBB pump. RH was defined by volume to first sensation >30%, urge to defecate >80%, or discomfort >100% (normalized to rectal capacity).

RESULTS

Fifty-three percent of constipated patients had RH. Patients with FDD had a significantly increased volume to first sensation (134.5 mL vs 102.0, P = 0.02), urge to defecate (187.0 mL vs 149.0, P = 0.04), and rectal capacity (253.5 mL vs 209.0, P = 0.04) compared to constipated patients without FDD. There was no difference in normalized sensory thresholds (percent of rectal capacity) nor the prevalence of hyposensitivity to each sensory threshold nor overall hyposensitivity.

CONCLUSION

Patients with FDD, when measured with the RBB, have increased sensory thresholds on volumetric distension, but RH was not observed when sensory threshold volume were normalized to rectal capacity. This may reflect "secondary" RH due to altered rectal biomechanics.

Factors associated with decreased anal sphincter tone and the accuracy of forced anal examinations to detect individuals having receptive anal intercourse: an observational study

Introduction

Forced anal examinations are used to prosecute sexual and gender minorities (SGM) in multiple countries under the presumption that decreased sphincter tone, assessed by a finger inserted into the anal canal, can detect persons practising receptive anal intercourse. Using baseline data from a longitudinal study, we aimed to determine factors associated with sphincter tone and the accuracy of sphincter tonality to detect persons engaging in receptive anal intercourse.

Methods

Clinicians in Chicago, Houston and Milwaukee, USA conducted digital anal rectal examinations (DARE) to score sphincter resting tone (RT) and squeeze tone (ST). On a separate survey, individuals reported their preferred position for anal intercourse, that is, either always/mostly insertive anal intercourse, always/mostly receptive anal intercourse or both receptive and insertive anal intercourse. Multivariable regression assessed factors associated with decreased sphincter tone while the area under the receiver operating characteristic curves (AUC) estimated the accuracy of sphincter tonality to detect receptive anal intercourse.

Results

Of 838 participants, 94.0% of whom were cisgendered males, 11.3% had decreased RT (95/838) and 6.3% had decreased ST (53/838). The accuracy of DARE to detect any receptive anal intercourse was little better than random guessing (AUC 0.53, 95% CI 0.51 to 0.55 and AUC 0.51, 95% CI 0.49 to 0.53, respectively). RT and ST decreased with age regardless of sexual behaviour (ptrend<0.01 for both). Compared with individuals having always/mostly insertive anal intercourse, individuals having always/mostly receptive anal intercourse were associated with decreased RT, but not ST, while those equally preferring both insertive and receptive anal intercourse were not associated with decreased RT or ST.

Conclusion

Decreased sphincter tone is uncommon among SGM who prefer receptive anal intercourse. Given virtually no accuracy, a finger inserted into the anus has no utility to detect individuals practising receptive anal intercourse and thus should not be used as such.

Trial registration number

NCT04090060.

Pleasurable and problematic receptive anal intercourse and diseases of the colon, rectum and anus

The ability to experience pleasurable sexual activity is important for human health. Receptive anal intercourse (RAI) is a common, though frequently stigmatized, pleasurable sexual activity. Little is known about how diseases of the colon, rectum, and anus and their treatments affect RAI. Engaging in RAI with gastrointestinal disease can be difficult due to the unpredictability of symptoms and treatment-related toxic effects. Patients might experience sphincter hypertonicity, gastrointestinal symptom-specific anxiety, altered pelvic blood flow from structural disorders, decreased sensation from cancer-directed therapies or body image issues from stoma creation. These can result in problematic RAI - encompassing anodyspareunia (painful RAI), arousal dysfunction, orgasm dysfunction and decreased sexual desire. Therapeutic strategies for problematic RAI in patients living with gastrointestinal diseases and/or treatment-related dysfunction include pelvic floor muscle strengthening and stretching, psychological interventions, and restorative devices. Providing health-care professionals with a framework to discuss pleasurable RAI and diagnose problematic RAI can help improve patient outcomes. Normalizing RAI, affirming pleasure from RAI and acknowledging that the gastrointestinal system is involved in sexual pleasure, sexual function and sexual health will help transform the scientific paradigm of sexual health to one that is more just and equitable.

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.

Rectal Sensory and Compliance Testing: A Method Comparison Study between High-Resolution Anorectal Manometry and Barostat Investigations

Abnormal visceral perception and motor function are often observed in patients with fecal incontinence, evacuation disorders and irritable bowel syndrome. The international anorectal physiology working group has proposed a standardization for anorectal function assessment, where rectal sensitivity testing is performed using an elastic balloon attached to a high-resolution anorectal manometry (HRAM) catheter. Rectal compliance, another component of rectal function evaluation, is a pressure-volume relationship that refers to the rectum's ability to stretch and expand as it receives and holds fecal matter. There are no data available regarding the possibility of compliance testing using HRAM, although this is theoretically possible by correcting for the elastic balloon's intrinsic properties. The gold standard for measurement of visceral sensitivity and compliance is the rectal barostat, according to the procedure described by the European COST action GENIEUR group. Data on the agreement between the two different procedures are scarce. Hence, we performed a comparative study of the HRAM and barostat investigations in 26 healthy individuals. We hypothesized that by inflating the balloon before the examination, rectal compliance can be measured with HRAM investigations, and we examined correlations and levels of agreement between the methods. Our results demonstrate that assessing rectal compliance with HRAM is technically possible; however, a strong correlation with the rectal barostat was only observed at the maximum tolerable volume (Spearman's rho = 0.7, p = 0.02). We only found moderate correlations (Spearman's rho = 0.562, p = 0.019) for compliance according to the barostat methodology and for rectal sensibility testing (Spearman's rho = 0.57, p = 0.03 for maximum tolerable volume). Bland-Altman plots showed poor levels of agreement between the methods. We conclude that HRAM and the rectal barostat cannot be used interchangeably for compliance or sensitivity assessments. We suggest the development of a non-elastic balloon with a fixed size and shape to assess rectal sensory function and compliance in HRAM testing.

Faecal incontinence-a comprehensive review

Introduction

Faecal incontinence (FI) is a distressing and often stigmatizing condition characterised as the recurrent involuntary passage of liquid or solid faeces. The reported prevalence of FI exhibits considerable variation, ranging from 7 to 15% in the general population, with higher rates reported among older adults and women. This review explores the pathophysiology mechanisms, the diagnostic modalities and the efficiency of treatment options up to date.

Methods

A review of the literature was conducted to identify the pathophysiological pathways, investigation and treatment modalities.

Result and discussion

This review provides an in-depth exploration of the intricate physiological processes that maintain continence in humans. It then guides the reader through a detailed examination of diagnostic procedures and a thorough analysis of the available treatment choices, including their associated success rates. This review is an ideal resource for individuals with a general medical background and colorectal surgeons who lack specialized knowledge in pelvic floor disorders, as it offers a comprehensive understanding of the mechanisms, diagnosis, and treatment of faecal incontinence (FI).

Rectal sensitivity and associated factors in patients with different subtypes of functional defecation disorder

OBJECTIVE

To investigate rectal sensitivity and associated factors in patients with different subtypes of functional defecation disorder (FDD).

METHODS

We segregated individuals diagnosed with FDD into two groups based on their defecation patterns: those with dyssynergic defecation and those with inadequate defecatory propulsion. We gathered general information through questionnaires and assessed rectal sensitivity using anorectal manometry. The rectal sensitivity performances of the two groups were compared; the factors related to rectal sensitivity were analyzed to determine the factors associated with rectal sensitivity, and the effect of biofeedback therapy on rectal sensitivity was clarified.

RESULTS

Rectal sensitivity in different subtypes of FDD decreased, and the difference between the two groups was not statistically significant ( P  > 0.05). There were no statistically significant differences in the first constant sensation volume, defecatory desire volume, and maximum tolerable volume between the different subtypes of FDD ( P  > 0.05). Multi-factor binary logistic regression analysis showed that age, constipation symptom score, and diabetes were all independent risk factors for decreased rectal sensitivity ( P  < 0.05). There were no statistically significant differences between the prior- and post-biofeedback therapy in the first constant sensation volume, defecatory desire volume, and maximum tolerable volume ( P  > 0.05).

CONCLUSION

Rectal sensitivity in different subtypes of FDD decreased. Age, constipation symptom score, and diabetes were independent risk factors for decreased rectal sensitivity. Short-term biofeedback therapy did not improve rectal hyposensitivity in patients with FDD.

Colorectal motility patterns and psychiatric traits in functional constipation and constipation-predominant irritable bowel syndrome: A study from China

BACKGROUND

Functional constipation (FC) and constipation-predominant irritable bowel syndrome (IBS-C) represent a spectrum of constipation disorders. However, the majority of previous clinical investigations have focused on Western populations, with limited data originating from China.

AIM

To determine and compare the colorectal motility and psychiatric features of FC and IBS-C in an Eastern Chinese population.

METHODS

Consecutive chronic constipation patients referred to our motility clinic from December 2019 to February 2023 were enrolled. FC and IBS-C diagnoses were established using ROME IV criteria, and patients underwent high-resolution anorectal manometry (ARM) and a colonic transmit test using the Sitz marker study. Constipation-related symptoms were obtained through questionnaires. Anxiety and depression were assessed by the Hamilton anxiety rating scale and the Hamilton Depression Rating Scale-21. The clinical characteristics and colorectal motility patterns of FC and IBS-C patients were compared.

RESULTS

No significant differences in sex, age or abdominal discomfort symptoms were observed between IBS-C and FC patients (all P > 0.05). The proportion of IBS-C patients with delayed colonic transit was higher than that of patients with FC (36.63% vs 15.91%, P < 0.05), while rectosigmoid accumulation of radiopaque markers was more common in the FC group than in the IBS-C group (50% vs 26.73%, P < 0.05). Diverse proportions of these dyssynergic patterns were noted within both the FC and IBS-C groups by ARM. IBS-C patients were found to have a higher prevalence of depression than FC patients (66.30% vs 42.42%, P < 0.05). The scores for feelings of guilt, suicide, psychomotor agitation, diurnal variation, obsessive/compulsive disorder, hopelessness, self-abasedment and gastrointestinal symptoms were significantly higher in IBS-C patients than that in FC patients (P < 0.05). For IBS-C (χ2 = 5.438, P < 0.05) but not FC, patients with normal colon transit time were significantly more likely to have anxiety than those with slow colon transit time. For IBS-C patients but not FC patients, the threshold of first constant sensation, desire to defecate and sustained urgency were all weakly correlated with the degree of anxiety (r = 0.414, r = 0.404, and r = 0.418, respectively, P < 0.05). The proportion of patients with a low threshold of desire to defecate among IBS-C patients with depression was lower than that in those without depression (69.6% vs 41.9%, χ2 = 4.054, P < 0.05).

CONCLUSION

Our findings highlight both overlapping and distinctive patterns of colon transit, dyssynergic patterns, anorectal sensation, psychological distress, and associations of psychiatric and colorectal motility characteristics in FC and IBS-C patients in an Eastern Chinese population, providing valuable insights into the pathophysiological underpinnings of these disorders.

The Mexican consensus on fecal incontinence

Fecal incontinence is the involuntary passage or the incapacity to control the release of fecal matter through the anus. It is a condition that significantly impairs quality of life in those that suffer from it, given that it affects body image, self-esteem, and interferes with everyday activities, in turn, favoring social isolation. There are no guidelines or consensus in Mexico on the topic, and so the Asociación Mexicana de Gastroenterología brought together a multidisciplinary group (gastroenterologists, neurogastroenterologists, and surgeons) to carry out the «Mexican consensus on fecal incontinence» and establish useful recommendations for the medical community. The present document presents the formulated recommendations in 35 statements. Fecal incontinence is known to be a frequent entity whose incidence increases as individuals age, but one that is under-recognized. The pathophysiology of incontinence is complex and multifactorial, and in most cases, there is more than one associated risk factor. Even though there is no diagnostic gold standard, the combination of tests that evaluate structure (endoanal ultrasound) and function (anorectal manometry) should be recommended in all cases. Treatment should also be multidisciplinary and general measures and drugs (lidamidine, loperamide) are recommended, as well as non-pharmacologic interventions, such as biofeedback therapy, in selected cases. Likewise, surgical treatment should be offered to selected patients and performed by experts.

Optimizing the Utility of Anorectal Manometry for Diagnosis and Therapy: A Roundtable Review and Recommendations

BACKGROUND & AIMS

Anorectal manometry (ARM) is a comprehensive diagnostic tool for evaluating patients with constipation, fecal incontinence, or anorectal pain; however, it is not widely utilized for reasons that remain unclear. The aim of this roundtable discussion was to critically examine the current clinical practices of ARM and biofeedback therapy by physicians and surgeons in both academic and community settings.

METHODS

Leaders in medical and surgical gastroenterology and physical therapy with interest in anorectal disorders were surveyed regarding practice patterns and utilization of these technologies. Subsequently, a roundtable was held to discuss survey results, explore current diagnostic and therapeutic challenges with these technologies, review the literature, and generate consensus-based recommendations.

RESULTS

ARM identifies key pathophysiological abnormalities such as dyssynergic defecation, anal sphincter weakness, or rectal sensory dysfunction, and is a critical component of biofeedback therapy, an evidence-based treatment for patients with dyssynergic defecation and fecal incontinence. Additionally, ARM has the potential to enhance health-related quality of life and reduce healthcare costs. However, it has significant barriers that include a lack of education and training of healthcare providers regarding the utility and availability of ARM and biofeedback procedures, as well as challenges with condition-specific testing protocols and interpretation. Additional barriers include understanding when to perform, where to refer, and how to use these technologies, and confusion over billing practices.

CONCLUSIONS

Overcoming these challenges with appropriate education, training, collaborative research, and evidence-based guidelines for ARM testing and biofeedback therapy could significantly enhance patient care of anorectal disorders.

Differential Findings on Anorectal Manometry in Patients with Parkinson's Disease and Defecatory Dysfunction

Introduction

Gastrointestinal dysfunction, particularly constipation, is among the most common non-motor manifestations in Parkinson's Disease (PD). We aimed to identify high-resolution anorectal manometry (HR-ARM) abnormalities in patients with PD using the London Classification.

Methods

We conducted a retrospective review of all PD patients at our institution who underwent HR-ARM and balloon expulsion test (BET) for evaluation of constipation between 2015 and 2021. Using age and sex-specific normal values, HR-ARM recordings were re-analyzed and abnormalities were reported using the London Classification. A combination of Wilcoxon rank sum and Fisher's exact test were used.

Results

36 patients (19 women) with median age 71 (interquartile range [IQR]: 69-74) years, were included. Using the London Classification, 7 (19%) patients had anal hypotension, 17 (47%) had anal hypocontractility, and 3 women had combined hypotension and hypocontractility. Anal hypocontractility was significantly more common in women compared to men. Abnormal BET and dyssynergia were noted in 22 (61%) patients, while abnormal BET and poor propulsion were only seen in 2 (5%). Men had significantly more paradoxical anal contraction and higher residual anal pressures during simulated defecation, resulting in more negative recto-anal pressure gradients. Rectal hyposensitivity was seen in nearly one third of PD patients and comparable among men and women.

Conclusion

Our data affirms the high prevalence of anorectal disorders in PD. Using the London Classification, abnormal expulsion and dyssynergia and anal hypocontractility were the most common findings in PD. Whether the high prevalence of anal hypocontractility in females is directly related to PD or other confounding factors will require further research.

Utility of Anorectal Testing to Predict Outcomes With Pelvic Floor Physical Therapy in Chronic Constipation: Pragmatic Trial

BACKGROUND & AIMS

We performed a clinical trial that aimed to inform the clinical utility of anorectal manometry (ARM) and balloon expulsion time (BET) as up-front tests to predict outcomes with community-based pelvic floor physical therapy as the next best step to address chronic constipation after failing an empiric trial of soluble fiber supplementation or osmotic laxatives.

METHODS

We enrolled 60 treatment-naïve patients with Rome IV functional constipation failing 2 weeks of soluble fiber supplementation or osmotic laxatives. All patients underwent ARM/BET (London protocol) followed by community-based pelvic floor physical therapy. Outcomes were assessed at baseline and 12 weeks. The primary end point was clinical response (Patient Assessment of Constipation-Symptoms instrument).

RESULTS

Fifty-three patients completed pelvic rehabilitation and the post-treatment questionnaire. Contemporary frameworks define dyssynergia on balloon expulsion time and dyssynergic patterns (ARM), but these parameters did not inform clinical outcomes (area under the curve [AUC], <0.6). Squeeze pressure (>192.5 mm Hg on at least 1 of 3 attempts; sensitivity, 47.6%; specificity, 83.9%) and limited squeeze duration (inability to sustain 50% of squeeze pressure for >20 seconds; sensitivity, 71.4%; specificity, 58.1%) were the strongest predictors of clinical outcomes. Combining BET with squeeze duration (BET greater than 6.5 seconds and limited squeeze duration) improved predictive accuracy (AUC, 0.75; 95% CI, 0.59-0.90). BET poorly predicted outcomes as a single test (AUC, 0.54; 95% CI, 0.38-0.69).

CONCLUSIONS

Using ARM to evaluate squeeze profiles, rather than dyssynergia, appears useful to screen patients with chronic constipation for up-front pelvic floor physical therapy based on likelihood of response. BET appears noninformative as a single screening test (ClinicalTrials.gov: NCT04159350).

Post-Operative Anorectal Manometry in Children following Anorectal Malformation Repair: A Systematic Review

Despite surgical correction, children with anorectal malformations may experience long-term bowel dysfunction, including fecal incontinence and/or disorders of evacuation. Anorectal manometry is the most widely used test of anorectal function. Although considerable attention has been devoted to its application in the anorectal malformation cohort, there have been few attempts to consolidate the findings obtained. This systematic review aimed to (1) synthesize and evaluate the existing data regarding anorectal manometry results in children following anorectal malformation repair, and (2) evaluate the manometry protocols utilized, including equipment, assessment approach, and interpretation. We reviewed four databases (Embase, MEDLINE, the Cochrane Library, and PubMed) for relevant articles published between 1 January 1985 and 10 March 2022. Studies reporting post-operative anorectal manometry in children (<18 years) following anorectal malformation repair were evaluated for eligibility. Sixty-three studies were eligible for inclusion. Of the combined total cohort of 2155 patients, anorectal manometry results were reported for 1755 children following repair of anorectal malformations. Reduced resting pressure was consistently identified in children with anorectal malformations, particularly in those with more complex malformation types and/or fecal incontinence. Significant variability was identified in relation to manometry equipment, protocols, and interpretation. Few studies provided adequate cohort medical characteristics to facilitate interpretation of anorectal manometry findings within the context of the broader continence mechanism. This review highlights a widespread lack of standardization in the anorectal manometry procedure used to assess anorectal function in children following anorectal malformation repair. Consequently, interpretation and comparison of findings, both within and between institutions, is exceedingly challenging, if not impossible. Standardized manometry protocols, accompanied by a consistent approach to analysis, including definitions of normality and abnormality, are essential to enhance the comparability and clinical relevance of results.

Association of delivery mode and number of pregnancies with anorectal manometry data in patients with postpartum constipation

OBJECTIVE

To explore the association of delivery mode and the number of pregnancies with anorectal manometry data in patients with postpartum constipation.

METHODS

This retrospective study included women with postpartum constipation treated at the pelvic floor rehabilitation department of Huzhou Maternity & Child Health Care Hospital between January 2018 and December 2019.

RESULTS

Among 127 patients included, 55 (43.3%) had one pregnancy, 72 (56.7%) had two pregnancies, 96 (75.6%) delivered spontaneously, 25 (16.7%) underwent Cesarean section, and six (4.7%) needed a Cesarean section despite spontaneous labor. The median duration of constipation was 12 months (range, 6-12). There were no differences between the two groups for any manometry parameters (all P > 0.05). The patients with a spontaneous delivery had a lower change in maximal contracting sphincter pressure compared with those with Cesarean section (14.3 (4.5-25.0) vs. 19.6 (13.4-40.0), P = 0.023). Only the delivery mode (Cesarean vs. spontaneous) independently affected the changes in contracting sphincter pressure (B = 10.32, 95%CI: 2.95-17.69, P = 0.006); age (P = 0.201), number of pregnancies (P = 0.190), and constipation duration (P = 0.161) were not associated.

CONCLUSION

The patients with a spontaneous delivery had a lower change in maximal contracting sphincter pressure compared with those with a Cesarean section, suggesting that patients with Cesarean may retain a better "push" function during defecation.

Dyssynergic Defecation: A Comprehensive Review on Diagnosis and Management

About one-third of chronically constipated patients have an evacuation disorder, and dyssynergic defecation is a common cause of the evacuation disorder. In dyssynergic defecation, the coordination between abdominal and pelvic floor muscles during defecation is disrupted and patients cannot produce a normal bowel movement. The etiology of dyssynergic defecation is still unknown. Although a detailed history taking and a careful examination including digital rectal examination could be useful, other modalities such as anorectal manometry and balloon expulsion test are necessary for the diagnosis. Biofeedback therapy is one of the most effective and safe treatments. Here, we provide an overview of dyssynergic defecation as well as how to diagnose and manage this condition.

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.

Novel insights into physiological mechanisms underlying fecal continence

The machinery maintaining fecal continence prevents involuntary loss of stool and is based on the synchronized interplay of multiple voluntary and involuntary mechanisms, dependent on cooperation between motor responses of the musculature of the colon, pelvic floor, and anorectum, and sensory and motor neural pathways. Knowledge of the physiology of fecal continence is key toward understanding the pathophysiology of fecal incontinence. The idea that involuntary contraction of the internal anal sphincter is the primary mechanism of continence and that the external anal sphincter supports continence only by voluntary contraction is outdated. Other mechanisms have come to the forefront, and they have significantly changed viewpoints on the mechanisms of continence and incontinence. For instance, involuntary contractions of the external anal sphincter, the puborectal muscle, and the sphincter of O'Beirne have been proven to play a role in fecal continence. Also, retrograde propagating cyclic motor patterns in the sigmoid and rectum promote retrograde transit to prevent the continuous flow of content into the anal canal. With this review, we aim to give an overview of primary and secondary mechanisms controlling fecal continence and evaluate the strength of evidence.

Clinical significance and related factors of rectal hyposensitivity in patients with functional defecation disorder

Background

Rectal hyposensitivity (RH) is not uncommon in patients with functional defecation disorder (FDD). FDD patients with RH are usually unsatisfied with their treatment.

Aims

The aim of this study was to find the significance of RH in patients with FDD and the related factors of RH.

Methods

Patients with FDD first completed clinical questionnaires regarding constipation symptoms, mental state, and quality of life. Then anorectal physiologic tests (anorectal manometry and balloon expulsion test) were performed. Rectal sensory testing (assessing rectal response to balloon distension using anorectal manometry) was applied to obtain three sensory thresholds. Patients were separated into three groups (non-RH, borderline RH, and RH) based on the London Classification. The associations between RH and clinical symptoms, mental state, quality of life, and rectal/anal motility were investigated.

Results

Of 331 included patients with FDD, 87 patients (26.3%) had at least one abnormally elevated rectal sensory threshold and 50 patients (15.1%) were diagnosed with RH. Patients with RH were older and mostly men. Defecation symptoms were more severe (p = 0.013), and hard stool (p < 0.001) and manual maneuver (p = 0.003) were more frequently seen in the RH group. No difference in rectal/anal pressure was found among the three groups. Elevated defecatory desire volume (DDV) existed in all patients with RH. With the number of elevated sensory thresholds increasing, defecation symptoms got more severe (r = 0.35, p = 0.001). Gender (male) (6.78 [3.07-15.00], p < 0.001) and hard stool (5.92 [2.28-15.33], p < 0.001) were main related factors of RH.

Conclusion

Rectal hyposensitivity plays an important role in the occurrence of FDD and is associated with defecation symptom severity. Older male FDD patients with hard stool are prone to suffer from RH and need more care.

Interdisciplinary consensus on the use of high-intensity magnetic stimulation in the treatment of pelvic floor muscle dysfunction manifested by anal incontinence

This paper presents interdisciplinary consensus on the use of protocols of high-intensity magnetic stimulation for the treatment of pelvic floor muscles dysfunction with anal incontinence in Russia.

AIM: to highlight the discussion and the decision-making on the basis of an interdisciplinary consensus on the use of a new algorithm of peripheral and transcranial magnetic stimulation in the treatment of pelvic floor muscles dysfunction with the clinic of anal incontinence.

RESULTS: the adoption of this consensus can serve as a basis for further research of this problem and optimize the results of treatment of patients with pelvic floor muscle dysfunction with anal incontinence. The data may be interesting for a wide range of medical specialists: general practitioners, gastroenterologists, coloproctologists, surgeons, neurosurgeons, gynecologists, urologists — anyone who encounter with manifestations of this disorder in a routine practice and chooses diagnostic and treatment options.

CONCLUSION: protocols for the treatment of anal incontinence using high-intensity magnetic stimulation aimed at improving the quality of treatment of patients with anal incontinence are based on the Russian experience of using the methods discussed and the analysis of the results obtained are validated.

Effects of non-invasive spinal cord stimulation on lower urinary tract, bowel, and sexual functions in individuals with chronic motor-complete spinal cord injury: Protocol for a pilot clinical trial

INTRODUCTION

Electrical spinal cord neuromodulation has emerged as a leading intervention for restoring autonomic functions, such as blood pressure, lower urinary tract (LUT), bowel, and sexual functions, following spinal cord injury (SCI). While a few preliminary studies have shown the potential effect of non-invasive transcutaneous spinal cord stimulation (tSCS) on autonomic recovery following SCI, the optimal stimulation parameters, as well as real-time and long-term functional benefits of tSCS are understudied. This trial entitled "Non-invasive Neuromodulation to Treat Bladder, Bowel, and Sexual Dysfunction following Spinal Cord Injury" is a pilot trial to examine the feasibility, dosage effect and safety of tSCS on pelvic organ function for future large-scale randomized controlled trials.

METHODS AND ANALYSIS

Forty eligible participants with chronic cervical or upper thoracic motor-complete SCI will undergo stimulation mapping and assessment batteries to determine the real-time effect of tSCS on autonomic functions. Thereafter, participants will be randomly assigned to either moderate or intensive tSCS groups to test the dosage effect of long-term stimulation on autonomic parameters. Participants in each group will receive 60 minutes of tSCS per session either twice (moderate) or five (intensive) times per week, over a period of six weeks. Outcome measures include: (a) changes in bladder capacity through urodynamic studies during real-time and after long-term tSCS, and (b) resting anorectal pressure determined via anorectal manometry during real-time tSCS. We also measure assessments of sexual function, neurological impairments, and health-related quality of life using validated questionnaires and semi-structured interviews.

ETHICS AND DISSEMINATION

Ethical approval has been obtained (CREB H20-01163). All primary and secondary outcome data will be submitted to peer-reviewed journals and disseminated among the broader scientific community and stakeholders.

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.

Research on improved intestinal image classification for LARS based on ResNet

Low anterior rectal resection is an effective way to treat rectal cancer at present, but it is easy to cause low anterior resection syndrome after surgery; so, a comprehensive diagnosis of defecation and pelvic floor function must be carried out. There are few studies on the classification of diagnoses in the field of intestinal diseases. In response to these outstanding problems, this research will focus on the design of the intestinal function diagnosis system and the image processing and classification algorithm of the intestinal wall to verify an efficient fusion method, which can be used to diagnose the intestinal diseases in clinical medicine. The diagnostic system designed in this paper makes up for the singleness of clinical monitoring methods. At the same time, the Res-SVDNet neural network model is used to solve the problems of small intestinal image samples and network overfitting, and achieve efficient fusion diagnosis of intestinal diseases in patients. Different models were used to compare experiments on the constructed datasets to verify the applicability of the Res-SVDNet model in intestinal image classification. The accuracy of the model was 99.54%, which is several percentage points higher than other algorithm models.

Current and future perspectives on the utility of provocative tests of anal sphincter function: A state-of-the-art summary

BACKGROUND

The maintenance of fecal continence depends upon coordinated interactions between the pelvic floor, anorectum, and anal sphincter complex orchestrated by central and peripheral neural activities. The current techniques to objectively measure anorectal function rely on fixed diameter catheters placed inside the anal canal with a rectal balloon to obtain measurements of anal resting and squeeze function, and rectal compliance. Until recently it had not been possible to measure the distensibility of the anal canal, or in other words its ability to resist opening against an increasing pressure, which has been proposed as the main determinant of a biological sphincter's function. Anal acoustic reflectometry (AAR) and the functional lumen imaging probe (FLIP) are two novel, provocative techniques that dynamically assess the anal sphincter complex under volume-controlled distension. In doing so, both provide information on the viscoelastic properties of the anal canal and offer new insights into its function.

PURPOSE

This review details the current and potential future applications of AAR and FLIP and highlights the unanswered questions relevant to these new technologies.

Intra-subject Variability in High Resolution Anorectal Manometry Using the London Classification: Diagnostic and Therapeutic Implications

This retrospective pilot study conducted on a community-based cohort of both men and women of various ages and underlying clinical presentations examined the durability and reproducibility of HR-ARM findings influencing their potential impact on clinical decision-making at the point of care (Jameson et al. in Br J Surg 81:1689-1692, 1994). The key finding of our study was that only a minority of patients who underwent repeat anorectal manometry as analyzed by the London Classification had stable manometric findings, raising questions regarding the validity of a single manometric measurement, as currently analyzed, for clinical decision-making.

Optimizing techniques for measuring anal resting and squeeze pressures with high-resolution manometry

BACKGROUND

The optimal methods for measuring and analyzing anal resting and squeeze pressure with high-resolution manometry (HRM) are unclear.

METHODS

Anal resting and squeeze pressures were measured with HRM in 90 healthy women, 35 women with defecatory disorders (DD), and 85 with fecal incontinence (FI). Pressures were analyzed with Manoview™ software and a customized approach. Resting pressures measured for 20, 60, and 300 s were compared. During the squeeze period, (3 maneuvers, 20 s each), the squeeze increment, which was averaged over 5, 10, 15, and 20 s, and squeeze duration were evaluated.

RESULTS

Compared to healthy women, the anal resting pressure, squeeze pressure increment, and squeeze duration were lower in FI (p ≤ 0.04) but not in DD. The 20, 60, and 300 s resting pressures were strongly correlated (concordance correlation coefficients = 0.96-0.99) in healthy and DD women. The 5 s squeeze increment was the greatest; 10, 15, and 20 s values were progressively lower (p < 0.001). The squeeze pressure increment and duration differed (p < 0.01) among the three maneuvers in healthy and DD women but not in FI women. The upper 95th percentile limit for squeeze duration was 19.5 s in controls, 19.9 s in DD, and 19.3 s in FI. Adjusted for age, resting pressure, and squeeze duration, a greater squeeze increment was associated with a lower risk of FI versus health (OR, 0.96; 95% CI, 0.94-0.97).

CONCLUSIONS

These findings suggest that anal resting and squeeze pressures can be accurately measured over 20 s. In most patients, one squeeze maneuver is probably sufficient.

Anal sphincter fatigability in assessing anal incontinence: A systematic review

BACKGROUND

Diagnosing anal incontinence (AI) based on manometry results is challenging due to the variation of the normal values and overlap between patients with and without AI. This study aimed to perform a systematic review on the difference in sphincter fatigability between patients with and without AI.

METHODS

MEDLINE, EMBASE, SCOPUS, and Google Scholar were searched. Studies were included if they included adult patients and assessed anal sphincter fatigability between using manometry. The effect size was estimated as the standardized mean difference (SMD) with 95% confidence intervals. A random-effects model was used.

RESULTS

The database searches identified 125 unique articles, and five additional articles were identified from the reference list of articles. One hundred thirteen were excluded through title and abstract review. Nine articles were included in the final analysis. There was no statistically significant difference in the resting pressure between the two groups. Patients with AI had significantly lower squeeze pressure. There was no statistically significant difference between the groups in the fatigue rate. The FRI was significantly lower in patients with AI (SMD 1.636, p = 0.001). Approximately a third of the patients in one study were able to maintain a contraction for 20s without reducing pressure. There was significant heterogeneity in the studies. The data available were inadequate for more robust calculations.

CONCLUSIONS

Sphincter fatigability, measured by the Fatigability Rate Index, has good discriminating power for anal incontinence. A standardized protocol needs to be followed by future researchers. Graphical Abstract The analysis used six studies with 413 patients to compare Fatigue Rate Index between patients with AI and controls. All studies reported a lower FRI in patients with incontinence and the FRI was significantly lower in patients with AI (standardized mean difference [SMD] 1.636, p= 0.001). Conflicting results were reported on the correlation between FRI and AI symptom scores.

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.

Colonic volume in patients with functional constipation or irritable bowel syndrome determined by magnetic resonance imaging

BACKGROUND

Functional constipation (FC) and irritable bowel syndrome constipation type (IBS-C) share many similarities, and it remains unknown whether they are distinct entities or part of the same spectrum of disease. Magnetic resonance imaging (MRI) allows quantification of intraluminal fecal volume. We hypothesized that colonic volumes of patients with FC would be larger than those of patients with IBS-C, and that both patient groups would have larger colonic volumes than healthy controls (HC).

METHODS

Based on validated questionnaires, three groups of participants were classified into FC (n = 13), IBS-C (n = 10), and HC (n = 19). The colonic volume of each subject was determined by MRI. Stool consistency was described by the Bristol stool scale and colonic transit times were assessed with radiopaque makers.

KEY RESULTS

Overall, total colonic volumes were different in the three groups, HC (median 629 ml, interquartile range (IQR)(562-868)), FC (864 ml, IQR(742-940)), and IBS-C (520 ml IQR(489-593)) (p = 0.001). Patients with IBS-C had lower colonic volumes than patients with FC (p = 0.001) and HC (p = 0.019), but there was no difference between FC and HC (p = 0.10). Stool consistency was similar in the two patient groups, but patients with FC had longer colonic transit time than those with IBS-C (117.6 h versus 43.2 h, p = 0.019).

CONCLUSION

Patients with IBS-C have lower total colonic volumes and shorter colonic transit times than patients with FC. Future studies are needed to confirm that colonic volume allows objective distinction between the two conditions.

Faecal incontinence in adults

Faecal incontinence, which is defined by the unintentional loss of solid or liquid stool, has a worldwide prevalence of ≤7% in community-dwelling adults and can markedly impair quality of life. Nonetheless, many patients might not volunteer the symptom owing to embarrassment. Bowel disturbances, particularly diarrhoea, anal sphincter trauma (obstetrical injury or previous surgery), rectal urgency and burden of chronic illness are the main risk factors for faecal incontinence; others include neurological disorders, inflammatory bowel disease and pelvic floor anatomical disturbances. Faecal incontinence is classified by its type (urge, passive or combined), aetiology (anorectal disturbance, bowel symptoms or both) and severity, which is derived from the frequency, volume, consistency and nature (urge or passive) of stool leakage. Guided by the clinical features, diagnostic tests and therapies are implemented stepwise. When simple measures (for example, bowel modifiers such as fibre supplements, laxatives and anti-diarrhoeal agents) fail, anorectal manometry and other tests (endoanal imaging, defecography, rectal compliance and sensation, and anal neurophysiological tests) are performed as necessary. Non-surgical options (diet and lifestyle modification, behavioural measures, including biofeedback therapy, pharmacotherapy for constipation or diarrhoea, and anal or vaginal barrier devices) are often effective, especially in patients with mild faecal incontinence. Thereafter, perianal bulking agents, sacral neuromodulation and other surgeries may be considered when necessary.

Post-operative anorectal manometry in children with Hirschsprung disease: A systematic review

BACKGROUND

Hirschsprung disease is commonly encountered by pediatric surgeons. Despite advances in the surgical management, these children may experience symptoms of bowel dysfunction throughout adulthood. Anorectal manometry may be used to assess post-operative anorectal structure and function. This review aimed to consolidate and evaluate the literature pertaining to post-operative findings of anorectal manometry in children with Hirschsprung disease.

PURPOSE

(1) Synthesize the available data regarding anorectal motility patterns in children following repair of Hirschsprung disease. (2) Evaluate the reported anorectal manometry protocols.

DATA SOURCES

We performed a systematic review of four databases: Embase, MEDLINE, the Cochrane Library, and PubMed.

STUDY SELECTION

This systematic review was performed in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Studies reporting results of post-operative anorectal manometry in children with Hirschsprung disease were evaluated for inclusion.

RESULTS

Twenty-three studies satisfied inclusion criteria, with a combined cohort of 939 patients. Post-operative anorectal manometry results were reported for 682 children. The majority of included studies were assessed as "poor quality." Disparate manometry protocols, heterogeneous cohorts, and lack of standardized outcome assessments introduced a risk of outcome reporting bias, limited the comparability of results, and impeded clinical translation of findings.

CONCLUSIONS

This systematic review demonstrated the lack of high-quality evidence underlying the current understanding of post-operative anorectal motility in children with HD. There was little consistency in reported manometry outcomes between studies. In future work, emphasis must be placed on the application of standardized manometry protocols, cohort reporting, and patient outcome assessments.

Abnormal Perception of Urge to Defecate: An Important Pathophysiological Mechanism in Women With Chronic Constipation

INTRODUCTION

Although the association of absent or attenuated "call to stool" with constipation is well-recognized, no studies have systematically evaluated the perception of urge to defecate in a well-defined cohort of patients with chronic constipation (CC).

METHODS

A prospective study of 43 healthy adult women and 140 consecutive adult women attending a tertiary center for investigation of CC. All participants completed a 5-day viscerosensory questionnaire, and all women with CC also underwent anorectal physiologic investigations. Normal urge perception and abnormal urge perception were defined using a Naive Bayes model trained in healthy women (95% having normal urge).

RESULTS

In total, 181 toilet visits in healthy women and 595 in women with CC were analyzed. Abnormal urge perception occurred in 70 (50.0%) women with CC. In this group, the urge to defecate was more often experienced as abdominal sensation (69.3% vs 41.4%; P < 0.0001), and the viscerosensory referral area was 81% larger (median pixels anterior: 1,849 vs 1,022; P < 0.0001) compared to women with CC and normal urge perception. Abnormal (vs normal) urge in women with CC was associated with more severe constipation (Cleveland Clinic constipation score: 19 vs 15 P < 0.0001), irritable bowel syndrome (45.7% vs 22.9% P < 0.0001), and a functional evacuation disorder on defecography (31.3% vs 14.3% P = 0.023). A distinct pattern of abnormal urge was found in women with CC and rectal hyposensitivity.

DISCUSSION

Abnormal urge perception was observed in 50% of women with CC and was frequently described as abdominal sensation, supporting the concept that sensory dysfunction makes an important contribution to the pathophysiology of constipation.