Diagnostic accuracy study of anorectal manometry for diagnosis of dyssynergic defecation

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.

Bionic concepts for assessment of defecatory function and dysfunction

Bionic technology is gaining momentum in medical research. In gastroenterology, bionic technologies such as the PillCam and SmartPill assess intestinal mucosa morphology and function during the gastrointestinal passage of the devices. Oral drug delivery devices and intestinal robots are other bionic technologies under development. Recently, Fecobionics, a simulated feces, was developed for assessment of anorectal (defecatory) function. It is an anally insertable device with shape and consistency like feces. The integrated device measures anorectal pressures, orientation, bending (a proxy of the anorectal angle), and the shape of the device when located in rectum and when being evacuated by patients. It integrates most elements of the current technologies on the market (balloon expulsion technology, high-resolution anorectal manometry, defecography, and the functional luminal imaging probe). Multiple measurements in a single study by a bionic device have obvious advantages since novel functional parameters can be computed. Several Fecobionics prototypes have been developed and evaluated in normal human subjects and in patients with fecal incontinence and defecatory disorders such as obstructed defecation. This paper provides an overview of the Fecobionics platform for assessment of defecatory function and dysfunction with a focus on design, signal processing, data analysis, current clinical trials, and future applications in diagnostics, therapy assessment, and therapy.

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.

Can Digital Rectal Examination Identify the Subtype of Dyssynergic Disorders as Well as High Resolution Anorectal Manometry?

Background and Aims

Diagnosing dyssynergic disorders (DD) often requires 3D high-definition anorectal manometry (3D-HRAM), raising concerns about cost, availability, and delayed referral. Digital rectal examination (DRE) offers a reliable, cost-effective alternative for DD diagnosis. This study aimed to assess DRE's capability to classify DD patients into the four subtypes outlined in Rao's classification.

Methods

This retrospective monocentric study involved patients diagnosed with DD through 3D-HRAM. After initial 3D-HRAM performed by one physician, patients underwent a clinical examination, including DRE by a second senior clinician blinded to DD subtypes. Statistical tests measured the correlation between DRE and HRAM in classifying the four DD subtypes.

Results

The study included 200 patients, revealing commendable overall agreement between DRE and 3D-HRAM (Kappa = 0.658). For subtype diagnosis, correlation was substantial for Subtypes I, II, and IV (0.679, 0.741, 0.649, respectively) and moderate for Subtype III (Kappa = 0.325).

Conclusion

DRE demonstrates satisfactory performance in diagnosing the four subtypes of DD. Enhanced training in DRE, emphasizing functional information, has the potential to reduce reliance on additional tests, thereby mitigating economic and organizational impacts.

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.

High-Resolution Anorectal Manometry and Balloon Expulsion Test Outcomes in Functional Constipation: A Comparative Study

BACKGROUND Functional constipation can occur in children and adults and consists of difficult or infrequent bowel movements, painful defecation, or the sensation of incomplete bowel movement, and it can be idiopathic. This study aimed to compare the findings from high-resolution anorectal manometry (HRAM) and the balloon expulsion test (BET) in 360 patients with functional constipation and 73 healthy volunteers. MATERIAL AND METHODS In total, 360 patients with functional constipation and 73 healthy volunteers underwent HRAM and BET in our hospital from January 2017 to December 2023. We collected the general data of all participants and surveyed the defecation symptoms of patients with functional constipation. RESULTS Our study showed no significant correlation between HRAM results and age in healthy volunteers, while men had a higher residual anal pressure (P=0.022), higher anal squeeze pressure (P=0.020), and lower rectoanal pressure gradient than women (P=0.017). Using logistic regression analysis, it was concluded that sex (OR=2.880, 95% CI [1.654,5.015], P=0.000) and sensation of incomplete evacuation (OR=1.892, 95% CI [1.023,3.500], P=0.042) affected the occurrence of dyssynergic defecation. The specificity of BET in diagnosing dyssynergic defecation was 81.89%, while that of HRAM was 52.78%. CONCLUSIONS This observation provides normal values for anorectal pressures by HRAM. HRAM and BET are effective methods for assessing functional constipation. Being male and having sensation of incomplete evacuation are risk factors for dyssynergic defecation. The specificity of BET for diagnosing dyssynergic defecation was higher than that of HRAM.

Management of abdominal bloating and distension, from subjective to objective

Abdominal distension is a clinical occurrence that involves a measurable, objective increase in abdominal circumference, which patients report as feeling like pregnant or like having a balloon inside the abdomen. This sign is often preceded by a subjective feeling of abdominal heaviness or bloating, reported as the sensation of having a huge amount of gas trapped inside. These manifestations are highly prevalent and may reflect on their own a gut-brain axis condition, such as functional abdominal distension, or be part of other disorders such as functional dyspepsia or irritable bowel syndrome (IBS). The prevalence of abdominal distension and bloating is 3.5 %. However, when associated with other gut-brain axis disorders such as dyspepsia or IBS, prevalence grows above 50 %. The etiology and pathophysiology of abdominal bloating and distension are highly complex and represent a challenge for both the practitioner and the patient. The patient often associates these sensations with trapped gas, and attributes them to some food intolerance, hence he/she adopts a highly restrictive diet that fails to resolve distension while incurring the risk of nutritional deficiencies or secondary dysbiosis, making a directed treatment guideline necessary.

Evidence-Based Clinical Guidelines for Chronic Constipation 2023

The Japan Gastroenterological Association published the first version of its clinical guidelines for chronic constipation 2023. Based on the latest evidence, these guidelines describe the definition, classification, diagnostic criteria, diagnostic testing methods, epidemiology, pathophysiology, and treatment of chronic constipation. They include flowcharts for both diagnosis and treatment of chronic constipation. In the treatment of chronic constipation, the first step involves differentiating between secondary forms, such as organic disease-associated constipation, systemic disease-associated constipation, and drug-induced constipation. The next step is to determine whether the chronic constipation stems from a motility disorder, a form of primary chronic constipation. For functional constipation and constipation-predominant irritable bowel syndrome, treatment should be initiated after evaluating symptoms like reduced bowel movement frequency type or defecation difficulty type. The first line of treatment includes the improvement of lifestyle habits and diet therapy. The first drugs to consider for oral treatment are osmotic laxatives. If these are ineffective, secretagogues and ileal bile acid transporter inhibitors are candidates. However, stimulant laxatives are exclusively designated for as-needed use. Probiotics, bulk-forming laxatives, prokinetics, and Kampo medicines, for which there is insufficient evidence, are considered alternative or complementary therapy. Providing the best clinical strategies for chronic constipation therapy in Japan, these clinical guidelines for chronic constipation 2023 should prove useful for its treatment worldwide. The Japan Gastroenterological Association published the first version of its clinical guidelines for chronic constipation 2023. Based on the latest evidence, these guidelines describe the definition, classification, diagnostic criteria, diagnostic testing methods, epidemiology, pathophysiology, and treatment of chronic constipation. They include flowcharts for both diagnosis and treatment of chronic constipation. In the treatment of chronic constipation, the first step involves differentiating between secondary forms, such as organic disease-associated constipation, systemic disease-associated constipation, and drug-induced constipation. The next step is to determine whether the chronic constipation stems from a motility disorder, a form of primary chronic constipation. For functional constipation and constipation-predominant irritable bowel syndrome, treatment should be initiated after evaluating symptoms like reduced bowel movement frequency type or defecation difficulty type. The first line of treatment includes the improvement of lifestyle habits and diet therapy. The first drugs to consider for oral treatment are osmotic laxatives. If these are ineffective, secretagogues and ileal bile acid transporter inhibitors are candidates. However, stimulant laxatives are exclusively designated for as-needed use. Probiotics, bulk-forming laxatives, prokinetics, and Kampo medicines, for which there is insufficient evidence, are considered alternative or complementary therapy. Providing the best clinical strategies for chronic constipation therapy in Japan, these clinical guidelines for chronic constipation 2023 should prove useful for its treatment worldwide.

Diagnostic value of balloon expulsion test and anorectal manometry in patients with constipation: a systematic review and meta-analysis

This study aims to compare the diagnostic value of balloon expulsion test and anorectal manometry in patients with constipation through meta-analysis. Databases, encompassing PubMed, EMBASE, Cochrane Library, Web of Science, etc. were searched for all English publications on the diagnosis of constipation using balloon expulsion test and anorectal manometry. The publication date was restricted from the inception of the databases until December 2022. Data analysis was carried out utilizing Stata 15.0 and Meta-Disc 1.4 software. Thirteen studies involving 2171 patients with constipation were included. According to the meta-analysis, the balloon expulsion test showed a pooled sensitivity of 0.75 (95% CI: 0.72-0.77), a pooled specificity (Spe) of 0.67 (95% CI: 0.62-0.72), a pooled positive likelihood ratio (+LR) of 3.24 (95% CI: 1.53-6.88), a pooled negative likelihood ratio (-LR) 0.35 (95% CI: 0.23-0.52) and a pooled diagnostic odds ratio (DOR) of 9.47 (95% CI: 3.27-27.44). For anorectal manometry, the pooled Sen, Spe, +LR, -LR and DOR were 0.74 (95% CI: 0.72-0.76), 0.73 (95% CI: 0.70-0.76), 2.69 (95% CI: 2.18-3.32), 0.35 (95% CI: 0.28-0.43), and 8.3 (95% CI: 5.4-12.75), respectively. The area under the summary receiver operating characteristic curve areas for balloon expulsion test and anorectal manometry were 0.8123 and 0.8088, respectively, with no statistically significant disparity (Z = -0.113, P > 0.05). Both the balloon expulsion test and anorectal manometry demonstrate comparable diagnostic performance, each offering unique advantages. These diagnostic procedures hold significance in the diagnosis of constipation.

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.

The rectum, anal sphincter and puborectalis muscle show different contraction wave forms during prolonged measurement with a simulated feces

Contractile patterns in rectum, puborectalis muscle and anal sphincter must be studied to understand defecation. Six subjects had contractile waveforms studied with Fecobionics. Symptom questionnaires, balloon expulsion test and anorectal manometry were done for reference. The Fecobionics bag was filled in rectum to urge-to-defecate volume and measurements were done for 4 h before the subjects attempted to evacuate the device. Pressures and bend angle (BA) variations were analyzed with Fast Fourier Transformation. Four normal subjects exhibited low frequency waves (< 0.06 Hz) for pressures and BA. The waves were uncoordinated between recordings, except for rear and bag pressures. Peak wave amplitudes occurred at 0.02-0.04 Hz. Pressures and the BA differed for peak 1 (p < 0.001) and peak 2 amplitudes (p < 0.005). The front pressure amplitude was bigger than the others (rear and BA, p < 0.05; bag, p < 0.005) for peak 1, and bigger than bag pressure (p < 0.005) and BA (p < 0.05) for peak 2. One subject was considered constipated with lower front pressure amplitudes compared to normal subjects and increased amplitudes for other parameters. The sixth subject was hyperreactive and differed from the other subjects. In conclusion, the rectum, anal sphincter and puborectalis muscle showed different contraction waves during prolonged measurements. The data call for larger studies to better understand normal defecation, feces-withholding patterns, and the implications on anorectal disorders.

Fecobionics in proctology: review and perspectives

Fecobionics is a novel integrated technology for assessment of anorectal function. It is a defecatory test with simultaneous measurements of pressures, orientation, and device angle (a proxy of the anorectal angle). Furthermore, the latest Fecobionics prototypes measure diameters (shape) using impedance planimetry during evacuation of the device. The simultaneous measurement of multiple variables in the integrated test allows new metrics to be developed including more advanced novel defecation indices, enabling mechanistic insight in the defecation process at an unprecedented level in patients with anorectal disorders including patients suffering from obstructed defecation, fecal incontinence, and low anterior resection syndrome. The device has the consistency and shape of a normal stool (type 3-4 on the Bristol Stool Form Scale). Fecobionics has been validated on the bench and in animal studies and used in clinical trials to study defecation phenotypes in normal human subjects and patients with obstructed defecation, fecal incontinence, and low anterior resection syndrome after rectal cancer surgery. Subtypes have been defined, especially of patients with obstructed defecation. Furthermore, Fecobionics has been used to monitor biofeedback therapy in patients with fecal incontinence to predict the outcome of the therapy (responder versus non-responder). Most Fecobionics studies showed a closer correlation to symptoms as compared to current technologies for anorectal assessment. The present article outlines previous and ongoing work, and perspectives for future studies in proctology, including in physiological assessment of function, diagnostics, monitoring of therapy, and as a tool for biofeedback therapy.

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.

Habit training versus habit training with direct visual biofeedback in adults with chronic constipation: A randomized controlled trial

AIM

The aim was to determine whether specialist-led habit training using Habit Training with Biofeedback (HTBF) is more effective than specialist-led habit training alone (HT) for chronic constipation and whether outcomes of interventions are improved by stratification to HTBF or HT based on diagnosis (functional defaecation disorder vs. no functional defaecation disorder) by radio-physiological investigations (INVEST).

METHOD

This was a parallel three-arm randomized single-blinded controlled trial, permitting two randomized comparisons: HTBF versus HT alone; INVEST- versus no-INVEST-guided intervention. The inclusion criteria were age 18-70 years; attending specialist hospitals in England; self-reported constipation for >6 months; refractory to basic treatment. The main exclusions were secondary constipation and previous experience of the trial interventions. The primary outcome was the mean change in Patient Assessment of Constipation Quality of Life score at 6 months on intention to treat. The secondary outcomes were validated disease-specific and psychological questionnaires and cost-effectiveness (based on EQ-5D-5L).

RESULTS

In all, 182 patients were randomized 3:3:2 (target 384): HT n = 68; HTBF n = 68; INVEST-guided treatment n = 46. All interventions had similar reductions (improvement) in the primary outcome at 6 months (approximately -0.8 points of a 4-point scale) with no statistically significant difference between HT and HTBF (-0.03 points; 95% CI -0.33 to 0.27; P = 0.85) or INVEST versus no-INVEST (0.22; -0.11 to 0.55; P = 0.19). Secondary outcomes showed a benefit for all interventions with no evidence of greater cost-effectiveness of HTBF or INVEST compared with HT.

CONCLUSION

The results of the study at 6 months were inconclusive. However, with the caveat of under-recruitment and further attrition at 6 months, a simple, cheaper approach to intervention may be as clinically effective and more cost-effective than more complex and invasive approaches.

The Relevance of the Excessive Perineal Descent in the Obstructed Defecation Syndrome: A Prospective Study of 141 Patients

BACKGROUND

Despite the widely accepted association between excessive straining and perineal descent, the clinical significance of perineal descent in patients with obstructed defecation syndrome is still unclear.

OBJECTIVE

This study aimed to evaluate the prevalence of pathological perineal descent in patients with obstructed defecation syndrome and the impact of perineal descent on symptoms severity.

DESIGN

This was a prospective multicenter uncontrolled study.

SETTINGS

The study involved 3 hospital pelvic-care centers and was conducted from January 2018 to January 2022.

PATIENTS

The study included 141 consecutive adult patients with an obstructed defecation syndrome score of 9 or more and no evidence of organic GI pathology. All the patients underwent dynamic pelvic MRI and, in case of suspected paradoxical puborectalis contraction, anal manometry.

MAIN OUTCOME MEASURES

Main outcome measures were the prevalence of excessive perineal descent and the correlation between perineal descent and obstructed defecation syndrome score.

RESULTS

One hundred twenty-eight patients (90.7%) completed magnetic resonance examination and were included in the analysis. Of these, 18 patients (14.1%) had a physiological perineal descent and 110 (85.9%) had an excessive perineal descent. Excessive perineal descent was found in 46.1% of patients (12/26) with MRI signs of paradoxical puborectalis contraction and in 96% of patients (98/102) with normal puborectalis relaxation. In this latter group of patients, a good correlation between obstructed defecation syndrome score and maximum perineal descent during straining was found (Spearman r test: 0.68; p < 0.0001).

LIMITATIONS

The study was limited by the small sample size and by the strong selection of the study population.

CONCLUSIONS

Excessive perineal descent is a common finding in patients with obstructed defecation syndrome and high symptoms score, occurring almost consistently in patients without paradoxical puborectalis contraction. In these patients, the maximum perineal descent seems to be well correlated with symptoms severity. See Video Abstract at http://links.lww.com/DCR/C135 .

LA RELEVANCIA DEL DESCENSO PERINEAL EXCESIVO EN EL SNDROME DE DEFECACIN OBSTRUIDA UN ESTUDIO PROSPECTIVO DE PACIENTES

ANTECEDENTES:A pesar de la asociación ampliamente aceptada entre el esfuerzo excesivo y el descenso perineal, la importancia clínica del descenso perineal en pacientes con síndrome de defecación obstruida aún no está clara.OBJETIVO:Evaluar la prevalencia del descenso perineal patológico en pacientes con síndrome de defecación obstruida y el impacto del descenso perineal en la severidad de los síntomas.DISEÑO:Este fue un estudio prospectivo multicéntrico no controladoENTORNO CLINICO:El estudio involucró a tres centros hospitalarios de atención pélvica y se llevó a cabo entre enero de 2018 y enero de 2022.PACIENTES:El estudio incluyó a 141 pacientes adultos consecutivos con puntuación del síndrome de defecación obstruida ≥ 9 y sin evidencia de patología gastrointestinal orgánica. A todas las pacientes se les realizó resonancia magnética pélvica dinámica y, en caso de sospecha de contracción puborrectal paradójica, manometría anal.PRINCIPALES MEDIDAS DE RESULTADO:Las principales medidas de resultado fueron la prevalencia del descenso perineal excesivo y la correlación entre el descenso perineal y la puntuación del síndrome de defecación obstruida.RESULTADOS:Ciento veintiocho (90,7%) pacientes completaron el examen de resonancia magnética y fueron incluidos en el análisis. De estos, 18 (14,1%) presentaron descenso perineal fisiológico y 110 (85,9%) descenso perineal excesivo. Se encontró descenso perineal excesivo en el 46,1% (12/26) de los pacientes con signos de contracción puborrectal paradójica en la resonancia magnética y en el 96% (98/102) de los pacientes con relajación puborrectal normal. En estos últimos pacientes se encontró una buena correlación entre la puntuación del síndrome de defecación obstruida y el descenso perineal máximo durante el esfuerzo (prueba r de Spearman: 0,68; p < 0,0001).LIMITACIONES:El estudio estuvo limitado por el pequeño tamaño de la muestra y por la fuerte selección de la población de estudio.CONCLUSIONES:El descenso perineal excesivo es un hallazgo común en pacientes con síndrome de defecación obstruida y alto puntaje de síntomas, ocurriendo casi constantemente en pacientes sin contracción puborrectal paradójica. En estos últimos pacientes el descenso perineal máximo parece estar bien correlacionado con la severidad de los síntomas. Consulte Video Resumen en http://links.lww.com/DCRC135 . (Traducción- Dr. Francisco M. Abarca-Rendon ).

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.

The patient with obstructed defecatory symptoms: Management differs considerably between physicians and surgeons

BACKGROUND

Patients with obstructed defecatory symptoms (ODS) are commonly referred to either gastroenterologists (GE) or colorectal surgeons (CS). Further management of these patients may be impacted by this choice of referral.

METHODS

An online survey of specialist practice was disseminated to GE and CS in Australia and New Zealand. A case vignette of a patient presenting with ODS was described, with multiple subsequent scenarios designed to delineate the responder's preferred approach to management of this patient.

KEY RESULTS

A total of 107 responders participated in the study, 62 CS and 45 GE. For a female patient with ODS not responding to pharmacological treatment, GE were more likely than CS to refer patients for anorectal manometry, while CS were more likely to refer for dynamic imaging. A quarter of CS and GE referred patients directly to pelvic floor physiotherapy, without any pre-treatment testing. Knowing the result of dynamic imaging, especially if a rectocele was demonstrated, substantially influenced management for both of the specialties: GE became more likely to refer the patients for CS consultation and less likely to refer directly for biofeedback or physiotherapy and CS were more likely to opt for an operative pathway over conservative management than they were prior to knowledge of the imaging findings. The majority (>75%) of GE and CS did not find it necessary to obtain a gynecological consultation, even in the presence of a rectocele.

CONCLUSIONS & INFERENCES

Practice variation across medical specialties affects diagnostic and management recommendations for patients with ODS, impacting treatment pathways. Our findings provide an incentive toward establishing interdisciplinary, uniform, management guidelines.

Rectal Prolapse Pathological Features: Findings in Patients With Outlet Obstruction Treated With Stapled Transanal Rectal Resection

BACKGROUND

Obstructed defecation syndrome is a common multifactorial disease for which treatment is based primarily on clinic presentation for the lack of reliable instrumental and anatomopathological criteria.

OBJECTIVE

The study aimed to analyze the pathological findings of the resected rectal specimens after stapled transanal rectal resection in patients affected by outlet obstruction.

DESIGN

Retrospective cohort study.

SETTINGS

University hospital.

PATIENTS

Patients who underwent rectal resection for obstructed defecation syndrome due to internal rectal prolapse were included.

INTERVENTIONS

Specimens of patients with obstructed defecation syndrome were analyzed through conventional histology and morphometric image analysis and compared with those of rectal specimens excised for oncological diseases.

MAIN OUTCOME MEASURES

Analysis of the anatomopathological impairments underlying rectal prolapse.

RESULTS

From January 2017 to December 2020, 46 specimens from the stapled transanal rectal resection group were compared with 40 specimens from the control group. In the stapled transanal rectal resection group, conventional histology revealed 34 samples (73.9%) had moderate- to severe-grade fibrosis with moderate-grade nerve degeneration in 33 cases (71.7%). In the control group, conventional histology revealed the absence of fibrosis in 31 specimens (77.5%), whereas the absence of nerve degeneration was detected in 37 specimens (92.5%). In the stapled transanal rectal resection group, morphometric image analysis showed severe-grade fibrosis in 25 cases (54.4%) compared to only low-grade fibrosis in 11 cases (27.5%).

LIMITATIONS

The small sample size and the retrospective design of the study were limitations. Moreover, there was no chance to use specimens from healthy volunteers as the control group.

CONCLUSIONS

Stapled transanal rectal resection specimens showed a higher rate of fibrosis and nerve dysplasia, an important parameter that is typically not considered preoperatively and could lead patients with rectal prolapse to the best treatment approach. See Video Abstract at http://links.lww.com/DCR/B928 .

CARACTERSTICAS ANATOMOPATOLGICAS EN EL PROLAPSO DE RECTO HALLAZGOS EN PACIENTES CON OBSTRUCCIN DEL TRACTO DE SALIDA TRATADOS CON RESECCIN RECTAL TRANSANAL CON GRAPAS

ANTECEDENTES:El síndrome de obstrucción del tracto de salida, es una afección multifactorial común, cuyo tratamiento está basado principalmente en la presentación clínica, ésto, debido a la falta de criterios confiables tanto instrumentales como anatomopatológicos.OBJETIVO:Analizamos los hallazgos histopatológicos de las piezas de resección rectal obtenidas por vía transanal mediante grapas, realizadas en pacientes que presentaban obstrucción del tracto de salida.DISEÑO:Este fue un estudio de cohorte retrospectivo.AJUSTE:El escenario fue un hospital universitario.PACIENTES:Aquellos sometidos a resección rectal por síndrome obstructivo del tracto de salida causada por un prolapso rectal interno.INTERVENCIONES:Los especímenes de pacientes con síndrome obstructivo defecatorio fueron analizados mediante histología convencional y análisis de imágenes morfométricas, comparados con especímenes rectales resecados por enfermedad oncológica.PRINCIPALES MEDIDAS DE RESULTADO:El resultado primario se concentró en la investigación de las deficiencias anatomopatológicas subyacentes del prolapso rectal interno.RESULTADOS:Desde enero de 2017 hasta diciembre de 2020, se compararon 46 especímenes del grupo de resección rectal transanal con grapas con 40 especímenes del grupo de control. En histología convencional, el grupo de resección rectal transanal con grapas, 34 muestras (73,9%) presentaron un grado de fibrosis moderada-severa con un grado moderado de degeneración neurógena en 33 casos (71,7%). En el grupo control, la histología convencional reveló ausencia de fibrosis en 31 especímenes (77,5 %), mientras que la ausencia de degeneración neurógena se detectó en 37 controles (92,5 %). En el grupo de resección rectal transanal con grapas, el análisis de imágenes morfométricas mostró fibrosis moderada y fibrosis severa en 19 (41,3%) y 25 (54,4%) casos, respectivamente. En el grupo control, el análisis de imágenes morfométricas mostró solo un bajo grado de fibrosis en 11 casos (27,5%). Se encontró una diferencia significativa en todos los grados de fibrosis y displasia neurógena entre los grupos en las evaluaciones de análisis de imagen morfométrica e histología convencional (p < 0,001).LIMITACIONES:El pequeño tamaño de la muestra y el diseño retrospectivo del estudio. Además, no existe la posibilidad de utilizar un grupo de control con muestras de voluntarios sanos.CONCLUSIONES:Los especímenes de resección rectal transanal con grapas mostraron una mayor tasa de fibrosis y displasia neurógena, parámetro importante que actualmente no está considerado antes de la operación y en un futuro muy cercano podría orientar a los pacientes con prolapso rectal interno hacia un mejor enfoque de tratamiento. Consulte Video Resumen en http://links.lww.com/DCR/B928 . (Traducción-Dr. Xavier Delgadillo ).

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.

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).

An Office-Based, Point-of-Care Test Predicts Treatment Outcomes With Community-Based Pelvic Floor Physical Therapy in Patients With Chronic Constipation

BACKGROUND & AIMS

Rectal evacuation disorders are common among constipated patients. We aimed to evaluate the accuracy of an investigational point-of-care test (rectal expulsion device [RED]) to predict outcomes with community-based pelvic floor physical therapy.

METHODS

We enrolled patients meeting Rome IV criteria for functional constipation failing fiber/laxatives for more than 2 weeks. RED was inserted and self-inflated, and then time-to-expel was measured in a left lateral position. All patients underwent empiric community-based pelvic floor physical therapy in routine care with outcomes measured at 12 weeks. The primary end point was global clinical response (Patient Assessment of Constipation Symptoms score reduction, >0.75 vs baseline). Secondary end points included improvement in health-related quality-of-life (Patient Assessment of Constipation Quality of Life score reduction, >1.0) and complete spontaneous bowel movement frequency (Food and Drug Administration complete spontaneous bowel movement responder definition).

RESULTS

Thirty-nine patients enrolled in a feasibility phase to develop the use-case protocol. Sixty patients enrolled in a blinded validation phase; 52 patients (mean, 46.9 y; 94.2% women) were included in the intention-to-treat analysis. In the left lateral position, RED predicted global clinical response (generalized area under the curve [gAUC], 0.67; 95% CI, 0.58-0.76]), health-related quality-of-life response (gAUC, 0.67; 95% CI, 0.58-0.77; P < .001), and complete spontaneous bowel movement response (gAUC, 0.63; 95% CI, 0.57-0.71; P < .001). As a screening test, a normal RED effectively rules out evacuation disorders (expected clinical response, 8.9%; P = .042). Abnormal RED in the left lateral position (defined as expulsion within 5 seconds or >120 seconds) predicted 48.9% clinical response to physical therapy. A seated maneuver enhanced the likelihood of clinical response (71.1% response with seated RED retained >13 seconds) but likely is unnecessary in most settings.

CONCLUSIONS

RED offers an opportunity to disrupt the paradigm by offering a personalized approach to managing chronic constipation in the community (Clinicaltrials.gov: NCT04159350).

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.

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.

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.

Fecal Incontinence and Defecatory Disorders in Patients With Ileal Pouch-Anal Anastomosis

Functional anorectal disorders are common in patients with ileal pouch-anal anastomosis (IPAA) and often have a debilitating impact on quality of life. The diagnosis of functional anorectal disorders, including fecal incontinence (FI) and defecatory disorders, requires a combination of clinical symptoms and functional testing. Symptoms are generally underdiagnosed and underreported. Commonly utilized tests include anorectal manometry, balloon expulsion test, defecography, electromyography, and pouchoscopy. The treatment for FI begins with lifestyle modifications and medications. Sacral nerve stimulation and tibial nerve stimulation have been trialed on patients with IPAA and FI, resulting in improvement in symptoms. Biofeedback therapy has also been used in patients with FI but is more commonly utilized in defecatory disorders. Early diagnosis of functional anorectal disorders is important because a response to treatment may significantly improve a patient's quality of life. To date, there is limited literature describing the diagnosis and treatment of functional anorectal disorders in patients with IPAA. This article focuses on the clinical presentation, diagnosis, and treatment of FI and defecatory disorders in patients with IPAA.

Comparison of Anorectal Manometry, Rectal Balloon Expulsion Test, and Defecography for Diagnosing Defecatory Disorders

BACKGROUND & AIMS

The utility of high-resolution anorectal manometry (HR-ARM) for diagnosing defecatory disorders (DDs) is unclear because healthy people may have features of dyssynergia. We aimed to identify objective diagnostic criteria for DD and to ascertain the utility of HR-ARM for diagnosing DD.

METHODS

Constipated patients were assessed with HR-ARM and rectal balloon expulsion time (BET), and a subset underwent defecography. Normal values were established by assessing 184 sex-matched healthy individuals. Logistic regression models evaluated the association of abnormal HR-ARM findings with prolonged BET and reduced rectal evacuation (determined by defecography).

RESULTS

A total of 474 constipated individuals (420 women) underwent HR-ARM and BET, and 158 underwent defecography. BET was prolonged, suggesting a DD, for 152 patients (32%). Rectal evacuation was lower for patients with prolonged vs normal BET. A lower rectoanal gradient during evacuation, reduced anal squeeze increment, and reduced rectal sensation were independently associated with abnormal BETs; the rectoanal gradient was 36% sensitive and 85% specific for prolonged BET. A lower rectoanal gradient and prolonged BET were independently associated with reduced evacuation. Among constipated patients, the probability of reduced rectal evacuation was 14% when the gradient and BET were both normal, 45% when either was abnormal, and 75% when both variables were abnormal.

CONCLUSIONS

HR-ARM, BET, and defecography findings were concordant for constipated patients, and reduced rectoanal gradient was the best HR-ARM predictor of prolonged BET or reduced rectal evacuation. Prolonged BET, reduced gradient, and reduced evacuation each independently supported a diagnosis of DD in constipated patients. We propose the terms probable DD for patients with an isolated abnormal gradient or BET and definite DD for patients with abnormal results from both tests.

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.

Anorectal volume-pressure relations, contraction work, and flow during defecation

Fecobionics is an integrated device that has shown promise for assessment of anorectal function. We used a wireless Fecobionics prototype to visualize defecatory patterns and to compute volume-pressure, contraction work, and flow. Twelve normal subjects were studied. The probe was 10 cm-long and contained pressure sensors and electrodes for impedance planimetry. Pressures, diameters, and volume data during defecation were analyzed. The bag was distended inside rectum to the urge-to-defecate level where after the subjects were asked to evacuate. The contraction work and defecatory flow were computed from the volume changes during expulsion. The minimum anal diameter during the evacuation was 17.6 ± 1.5 mm. The middle diameter recording was 10-20% lower than the front diameter channels and 10-20% bigger than the rear channels. The bag volume at urge correlated with the minimum diameter (r = 0.63). The diameter-pressure and volume-pressure loops were counterclockwise with phases of bag filling, isometric contraction, ejection and anal passage. The defecatory contraction work was 3520 ± 480 mL × cmH2O. The maximum flow during defecation was 302 ± 33 mL/s. The flow was associated with the anal diameter (r = 0.84) but not with the rectoanal pressure gradient (r = 0.14). Volume-pressure loops have a tremendous impact on the understanding of cardiopulmonary pathophysiology. Future studies will shed light on potential clinical impact in defecatory pathophysiology.

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.

Intra- and inter-observer agreement in the classification of dyssynergic defecation on high-resolution anorectal manometry using water-perfusion system

BACKGROUND AND AIMS

Dyssynergic defecation (DD) classified on anorectal manometry is based on variations in anal sphincter pressures and rectal pressure generated during bearing down. There is a paucity of data on intra- and inter-observer agreement in the classification of DD on high-resolution anorectal manometry (HRAM) using a water-perfusion system.

METHODS

This cross-sectional observational study was conducted between June 2014 and May 2016 on 70 adult patients with DD. Observer 1 did the baseline analysis and reanalyzed the readings at least 6 months later, blinded to the initial analysis results (intra-observer variability). Four other blinded observers (5-25 years in anorectal manometry and minimum 5 years of experience in HRAM) then individually analyzed the manometry data (inter-observer variability).

RESULTS

Intra-observer agreement was excellent (kappa 0.862) for classifying DD. Agreement between the six observations (i.e. two from observer 1 and four from independent observers) was also good (kappa 0.632). The highest agreement was for type 4 DD (kappa 0.738), followed by type 1 (0.680), type 2 (0.664), and type 3 (0.537). Cronbach's alpha value was 0.93, suggesting excellent internal consistency.

CONCLUSION

The diagnosis of the types of DD on anorectal manometry using a water-perfusion system has excellent intra-observer and good inter-observer agreement .

Gastrointestinal motility disorders in patients with multiple sclerosis: A single-center study

BACKGROUND

Most prevalent gastrointestinal symptoms in multiple sclerosis (MS) relate to lower bowel dysfunction, often in association with bladder manifestations.

OBJECTIVE

To assess clinical and objective gastrointestinal motor dysfunctions in patients with MS.

METHODS

This was a single-center, retrospective study of 166 patients evaluated between 1996 and 2020. We reviewed characterization of the MS, gastrointestinal and neurological symptoms, measurements of gastrointestinal and colonic transit, and anorectal manometry.

KEY RESULTS

At the time of the gastrointestinal evaluations of the 166 patients with MS (138 women; 83%), 111 were in the relapsing-remitting phase and 52 were in the progressive phase. In 3 patients, disease phase was not assigned due to insufficient data. Constipation was identified in 82% (136/166) of patients. Most [103/116 (88%)] patients with bladder symptoms also had constipation or fecal incontinence. Delayed gastric emptying at 4 h and colonic transit at 24 h was identified in 16% and 7% of the cohort, respectively; 22% had accelerated gastric emptying. On anorectal manometry, resting anal sphincter pressure >90 mm Hg and rectoanal pressure differential below -50mm Hg suggested evacuation disorder in patients with constipation.

CONCLUSIONS AND INFERENCES

In addition to slow colonic transit and anorectal dysfunction leading to constipation in MS, 22% of patients had accelerated gastric emptying.

Fecobionics characterization of female patients with fecal incontinence

Defecatory disorders including fecal incontinence (FI) are diagnosed on the symptom pattern supplemented by anorectal manometry (ARM), the balloon expulsion test (BET), and endo-anal ultrasonography. In this study, we used a simulated stool named Fecobionics to study distinct defecation patterns in FI patients using preload-afterload diagrams and to provide comparative data on defecation indices (DIs) between passive and urge incontinent patients. All subjects had Fecobionics, endo-anal ultrasonography and ARM-BET done. The Fecobionics bag was distended in rectum until urge in 37 female patients (64.1 ± 1.5 yrs) and a group of normal subjects (NS, 12F, age 64.8 ± 2.8 yrs). Rear-front pressure (preload-afterload) diagrams and DIs were compared between groups. The FISI score in the patients was 8.6 ± 0.6. The NS did not report FI-related symptoms. All patients and NS defecated Fecobionics and ARM-BET within 2 min. The urge volume was 46.1 ± 3.6 and 35.3 ± 5.9 mL in the FI and normal groups (P > 0.1). The expulsion duration was 14.8 ± 2.4 and 19.8 ± 5.1 s for the two groups (P > 0.1). The preload-afterload diagrams demonstrated clockwise loops that clearly differed between the FI subtypes and NS. The DIs showed profound difference between patients and NS. Fecobionics data showed higher correlation with symptoms in FI patients than ARM-BET. Fecobionics obtained novel pressure signatures in subtypes of FI patients and NS. Fecobionics provides DI data that cannot be obtained with ARM-BET.

Feasibility study of defecation studied with a wireless Fecobionics probe in normal subjects

Several technologies have been developed for assessing anorectal function including the act of defecation. We used a new prototype of the Fecobionics technology, a multi-sensor simulated feces, to visualize defecatory patterns and introduced new metrics for anorectal physiology assessment in normal subjects. Fourteen subjects with normal fecal incontinence and constipation questionnaire scores were studied. The 10-cm-long Fecobionics device provided measurements of axial pressures, orientation, bending, and shape. The Fecobionics bag was distended to the urge-to-defecate level inside rectum where after the subjects were asked to evacuate. Physiological evacuation parameters were assessed. Special attention was paid to the Fecobionics rectoanal pressure gradient (F-RAPG) during evacuation. Anorectal manometry (ARM) and balloon expulsion test (BET) were done as references. The user interface displayed the fine coordination between pressures, orientation, bending angle, and shape. The pressures showed that Fecobionics was expelled in 11.5 s (quartiles 7.5 and 18.8s), which was shorter than the subjectively reported expulsion time of the BET balloon. Six subjects did not expel the BET balloon within 2 min. The F-RAPG was 101 (79-131) cmH₂ O, whereas the ARM-RAPG was -28 (-5 to -47) cmH₂ 0 (p < 0.001). There was no association between the two RAPGs (r²  = 0.19). Fecobionics showed paradoxical contractions in one subject (7%) compared to 12 subjects with ARM (86%). Fecobionics obtained novel physiological data. Defecatory patterns and data are reported and can be used to guide larger-scale studies in normal subjects and patients with defecatory disorders. In accordance with other studies, this Fecobionics study questions the value of the ARM-RAPG.

Fecobionics Evaluation of Biofeedback Therapy in Patients With Fecal Incontinence

INTRODUCTION

Biofeedback therapy (BFT) is a well-known treatment for functional anorectal disorders. The effect of BFT was monitored in fecal incontinence (FI) patients with the Fecobionics test and with the conventional technologies, anorectal manometry (ARM) and balloon expulsion test (BET).

METHODS

Studies were performed in 12 patients before and after 8 weeks of biofeedback training. The Fecal Incontinence Severity Index (FISI) score was obtained. Anal resting and squeeze pressures were measured before the bag was distended in the rectum until urge to defecate. Pressure recordings were made during Fecobionics evacuation.

RESULTS

BFT resulted in 24% reduction in FISI scores (P < 0.01). Seven patients were characterized as responders. Anal pressures, the urge-to-defecate volume, and defecatory parameters did not change significantly during BFT. For ARM-BET, the maximum anal squeeze pressure, the urge-to-defecate volume, and the expulsion time were lower after BFT compared with those before BFT (P < 0.05). For Fecobionics, the change in urge volume (r = 0.74, P < 0.05) and the change in defecation index (r = 0.79, P < 0.01) were associated with the change in FISI score. None of the ARM-BET parameters were associated with the change in FISI score. It was studied whether any pre-BFT data could predict treatment success. The Fecobionics expulsion duration and the defecation index predicted the outcome (P < 0.05). The defecation index had a sensitivity of 100% and a specificity of 72%. None of the ARM-BET parameters predicted the outcome (all P > 0.2).

DISCUSSION

Fecobionics was used as a tool to monitor the effect of BFT and proved better than conventional technologies for monitoring and predicting the outcome in the FISI score.

Inadequate Rectal Pressure and Insufficient Relaxation and Abdominopelvic Coordination in Defecatory Disorders

BACKGROUND & AIMS

Diagnostic tests for defecatory disorders (DDs) asynchronously measure anorectal pressures and evacuation and show limited agreement; thus, abdominopelvic-rectoanal coordination in normal defecation and DDs is poorly characterized. We aimed to investigate anorectal pressures, anorectal and abdominal motion, and evacuation simultaneously in healthy and constipated women.

METHODS

Abdominal wall and anorectal motion, anorectal pressures, and rectal evacuation were measured simultaneously with supine magnetic resonance defecography and anorectal manometry. Evacuators were defined as those who attained at least 25% rectal evacuation. Supervised (logistic regression and random forest algorithm) and unsupervised (k-means cluster) analyses identified abdominal and anorectal variables that predicted evacuation.

RESULTS

We evaluated 28 healthy and 26 constipated women (evacuators comprised 19 healthy participants and 8 patients). Defecation was initiated by abdominal wall expansion that was coordinated with anorectal descent, increased rectal and anal pressure, and then anal relaxation and rectal evacuation. Compared with evacuators, nonevacuators had lower anal diameters during simulated defecation, rectal pressure, anorectal junction descent, and abdominopelvic-rectoanal coordination (P < .05). Unsupervised cluster analysis identified 3 clusters that were associated with evacuator status (P < .01), that is, 10 evacuators (83%), 16 evacuators (73%), and 1 evacuator (5%) in clusters 1, 2, and 3, respectively. Each cluster had distinct characteristics (eg, maximum abdominosacral distance, rectal pressure, anorectal junction descent, anal diameter) and correlates that were more (clusters 1-2) or less (cluster 3) conducive to evacuation. Cluster 2 had 16 evacuators (73%) and intermediate characteristics (eg, lower anal resting pressure and relaxation during evacuation; P < .05).

CONCLUSIONS

Women with DDs and a modest proportion of healthy women had specific patterns of anorectal dysfunction, including inadequate rectal pressurization, anal relaxation, and abdominopelvic-rectoanal coordination. These observations may guide individualized therapy for DDs in the future.

Belgian consensus on irritable bowel syndrome

BACKGROUND

Irritable bowel syndrome (IBS) is characterised by recurrent abdominal pain related to defaecation or associated with altered stool frequency or consistency. Despite its prevalence, major uncertainties in the diagnostic and therapeutic management persist in clinical practice.

METHODS

A Delphi consensus was conducted by 20 experts from Belgium, and consisted of literature review and voting process on 78 statements. Grading of recommendations, assessment, development and evaluation criteria were applied to evaluate the quality of evidence. Consensus was defined as > 80 % agreement.

RESULTS

Consensus was reached for 50 statements. The Belgian consensus agreed as to the multifactorial aetiology of IBS. According to the consensus abdominal discomfort also represents a cardinal symptom, while bloating and abdominal distension often coexist. IBS needs subtyping based on stool pattern. The importance of a positive diagnosis, relying on history and clinical examination is underlined, while additional testing should remain limited, except when alarm features are present. Explanation of IBS represents a crucial part of patient management. Lifestyle modification, spasmolytics and water-solube fibres are considered first-line agents. The low FODMAP diet, selected probiotics, cognitive behavioural therapy and specific treatments targeting diarrhoea and constipation are considered appropriate. There is a consensus to restrict faecal microbiota transplantation and gluten-free diet, while other treatments are strongly discouraged.

CONCLUSIONS

A panel of Belgian gastroenterologists summarised the current evidence on the aetiology, symptoms, diagnosis and treatment of IBS with attention for the specificities of the Belgian healthcare system.

Functional anorectal studies in patients with low anterior resection syndrome

BACKGROUND

Most patients who have undergone low anterior resection suffer from bowel dysfunction postoperatively. This condition is referred to as low anterior resection syndrome (LARS). The aim was to study defecatory patterns in LARS patients compared to a primary control group of fecal incontinence (FI) patients and normal subjects (NS) with the Fecobionics device.

METHODS

Fecobionics expulsion parameters were assessed in an interventional study design. The Fecobionics probe contained pressure sensors at the front, rear, and inside the bag. The bag was distended until urge sensation in rectum in 11 LARS patients (5F/6M, 63.2 ± 2.9 years), 11 FI subjects (7F/4M, 64.4 ± 2.5 years), and 11 NS (7F/4M, 63.6 ± 3.0 years). Defecation indices were computed from the Fecobionics data. All subjects had high-resolution anorectal manometry (ARM) and balloon expulsion test (BET) done. Symptoms were evaluated with LARS and Wexner scores.

KEY RESULTS

The LARS score in the LARS patients was 39.0 ± 0.6. The Wexner score in the LARS, FI, and NS groups was 14.2 ± 0.7, 10.1±1.0, and 0.0 ± 0.0 (p < 0.01). The resting anal pressure and squeeze pressure were lowest in LARS patients (p < 0.05). The urge volume was 11.8 ± 4.2, 59.6 ± 6.4, and 41.6 ± 6.4 ml in the LARS, FI, and NS groups, respectively (p < 0.001). The expulsion duration did not differ between groups. Defecation indices were lowest in the LARS patients (p < 0.05). ARM-BET confirmed the low urge volume in LARS patients whereas anal pressures did not differ between groups.

CONCLUSIONS AND INFERENCES

The LARS patients had low anal pressures and urge volume. Most Defecation Indices differed between the LARS group and the other groups.

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.