Validation of the balloon evacuation test: reproducibility and agreement with findings from anorectal manometry and electromyography

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.

Rome Foundation Working Team Report on overlap in disorders of gut-brain interaction

In patients with disorders of gut-brain interaction (DGBI), overlapping non-gastrointestinal conditions such as fibromyalgia, headaches, gynaecological and urological conditions, sleep disturbances and fatigue are common, as is overlap among DGBI in different regions of the gastrointestinal tract. These overlaps strongly influence patient management and outcome. Shared pathophysiology could explain this scenario, but details are not fully understood. This overlap has been shown to be of great relevance for DGBI. In addition, symptoms considered to be caused by a DGBI could have a detectable organic cause, and in patients with a diagnosed organic gastrointestinal disease, symptoms not clearly explained by the pathology defining this organic disease are common. Thus, the aims of this Rome Foundation Working Team Report were to review the literature on overlapping conditions among patients with paediatric and adult DGBI and, based on the available epidemiological and clinical evidence, make recommendations for the current diagnostic and therapeutic approach, and for future research. Specifically, we focused on other DGBI in the same or different gastrointestinal anatomical region(s), DGBI overlap with organic bowel diseases in remission, and DGBI overlap with non-gastrointestinal, non-structural conditions.

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.

Identification of functional defecation disorder in patients with constipation based on colonic transit test: a retrospective study

BACKGROUND

This study aims to evaluate the diagnostic efficacy of colonic transit test (CTT) in cases of constipation associated with functional defecation disorders (FDD) within the Chinese population.

METHODS

A retrospective analysis was conducted involving 202 patients diagnosed with functional constipation, who underwent CTT, high-resolution anorectal manometry, and balloon expulsion test. Participants were categorized based on the Rome IV criteria, comprising 103 patients with FDD and 99 without. The study examined the symptomatic characteristics of both groups and assessed the diagnostic utility of CTT in identifying constipation with FDD.

RESULTS

The predominant symptom reported among individuals with chronic functional constipation was excessive straining, observed in 69.3% of cases. The incidence of hard stool passage and feelings of incomplete evacuation were significantly greater in the FDD group compared to the non-FDD group (47.6% vs. 31.3%, p = 0.018 and 50.5% vs. 25.3%, p = 0.001, respectively). The presence of three or more rectosigmoid (RS) residual markers and a transit index of 40% or greater demonstrated moderate diagnostic value for FDD, characterized by low sensitivity(44.7% and 47.6%) but high specificity(76.8% and 75.8%). The RS residual markers were effective in differentiating between FDD and normal transit constipation, but not effectively distinguish between FDD and slow transit constipation.

CONCLUSIONS

The presence of RS residue serves primarily as an exclusionary criterion for diagnosing FDD. In cases of slow transit constipation, but not normal transit constipation, it is imperative to conduct multiple kinetic assessments to accurately differentiate between FDD and other types of constipation.

Biofeedback efficacy for outlet dysfunction constipation: Clinical outcomes and predictors of response by a limited approach

BACKGROUND

Functional defecation disorders (FDD) are a common etiology of refractory chronic constipation (CC). FDD diagnosis (dyssynergic defecation [DD] and inadequate defecatory propulsion [IDP]), requires diagnostic tests including anorectal manometry (ARM) and balloon expulsion test (BET). Biofeedback (BF) is the treatment of choice for DD. The aims of our study were to evaluate: the outcome of BF in a group of constipated patients with defecatory disorders of any etiology; the efficacy of two simple diagnostic tools in predicting BF outcome in the short-term.

METHODS

One hundred and thirty-one refractory CC patients failing the BET underwent BF therapy. Before BF, all patients underwent the following: ARM. Straining questionnaire. The answers were: "belly muscles"; "anal muscles"; "both"; "Don't know/No answer." Digital rectal examination augmented by abdominal palpation on straining (augmented-DRE). The BF therapist was blinded to ARM, straining questionnaire, and augmented-DRE results.

KEY RESULTS

Eighty-one patients responded to BF. Gender, age, and IBS-C showed no significant impact on BF response. Both DD and IDP responded equally to BF, while the rate of response in patients with isolated structural pelvic floor abnormalities was lower (p < 0.001). The answer "anal muscles" to straining questionnaire showed a strong association with BF response (p < 0.001). A lack in abdominal contraction and in anal relaxation on augmented-DRE were strongly associated with BF response (p < 0.01). Absence of manual maneuvers to facilitate defecation was associated with BF response (p < 0.001).

CONCLUSIONS & INFERENCES

BF is the therapy of choice for refractory constipation due to FDD of any etiology, inducing both clinical and anorectal physiology improvement in the short term. Comorbid IBS-C did not affect outcome while symptomatic isolated pelvic floor abnormalities appeared refractory to behavior treatment. The straining questionnaire and augmented-DRE outcomes showed a strong correlation with BF response and can be implemented in clinical practice to improve the management of constipated patients by prompting early referral to BF.

Feasibility of IAPWG protocol in performing high-definition three-dimensional anorectal manometry: A prospective, multicentric italian study

BACKGROUND

The International Anorectal Physiology Working Group (IAPWG) suggests a standardized protocol to perform high-resolution anorectal manometry. The applicability and possible limitations of the IAPWG protocol in performing three-dimensional high-definition anorectal manometry (3D-ARM) have still to be extensively evaluated.

METHODS

The IAPWG protocol was applied in performing 3D-ARM. Anorectal manometry (ARM) and a balloon expulsion test (BET) were performed according to IAPGW protocol in 290 patients.

KEY RESULTS

A total of 84 males and 206 females (mean age 57.1 ± 15.7 years) were enrolled in six Italian centers. The reasons for which the patients were sent to perform 3D-ARM were: constipation (53.1%), fecal incontinence (26.9%), anal pain (3.1%), postsurgical (3.8%) and presurgical evaluation (4.8%), prolapse (3.4%), anal fissure (2.8%), and other (2.1%). Due to organic and functional conditions (low rectal anterior resections, rectal prolapses, and J-pouch after colectomy), we were unable to perform a complete 3D-ARM on six patients. Overall, a complete 3D-ARM and BET following IAPWG protocol was carried out in 284 patients (97.9%). The following were recorded: rest pressure (81.9 ± 32.0 mmHg) and length of the anal sphincter (37.0 ± 6.2 cm), maximum anal squeeze pressure (201.6 ± 81.3 mmHg), squeeze duration (22.0 ± 8.8 s), maximum rectal (48.7 ± 41.0 mmHg) and minimum anal pressure (73.3 ± 36.5 mmHg) during push, presence/absence of a dyssynergic pattern, cough reflex and rectal sensations (first constant sensation 48.4 ± 29.5 mL, desire to defecate 83.7 ± 52.1 mL, and maximum tolerated volume 149.5 ± 72.6 mL), and presence/absence of rectoanal inhibitory reflex. Mean 3D-ARM registration time was 14 min 7 s ± 3 min 12 s.

CONCLUSIONS

This is the first multicentric study that evaluates the applicability of the IAPWG protocol in 3D-ARM performed in different manometric laboratories (both gastroenterological and surgical). The IAPWG protocol was easy to perform and was not time consuming. A diagnosis according to the London Classification was easily obtained in most patients in which 3D-ARM was carried out. No clear limitations to the applicability of the IAPWG protocol were detected.

Consistency of Feces Affects Defecatory Function

Background/Aims

It is a common belief that constipated patients have hard feces that contributes to the difficulties defecating. To the best of our knowledge, no studies had been published on controlled evacuation of simulated feces with different consistencies.

Methods

Twelve normal subjects were recruited for studies with the simulated feces device "Fecobionics" of different consistency (silicone shore 0A-40A corresponding to Bristol stool form scale types 2-4). The subjects filled out questionnaires and had the balloon expulsion test and anorectal manometry done for reference. The Fecobionics probes were inserted in rectum in random order with +20 minutes between insertions. The bag was filled to urge-to-defecate and evacuations took place in privacy. Non-parametric statistics with median and quartiles are provided.

Results

One subject was excluded due to technical issues, and another had abnormal anorectal manometry-balloon expulsion test. The 4 females/6 males subjects were aged 23 (range 20-48) years. Most differences were observed between the 0A and 10A probe (duration, maximum bag pressure, duration x maximum bag pressure, and relaxation of the front pressure and the bend angle during evacuation), eg, the duration was 9 (8-12) seconds at 0A and 18 (12-21) seconds at 10A (P < 0.05), and maximum bag pressure was 107 (96-116) cmH2O at 0A and 140 (117-162) cmH2O at 10A (P < 0.05). The bend angle before evacuation differed between the probes whereas only the 10A differed from 40A during defecation. The 10A was harder to evacuate than the 0A probe. Except for the bend angles, no further significant change was observed from 10A to 40A.

Conclusion

Fecal consistency affects defecatory parameters.

Functional Constipation and Obstructed Defecation

Constipation encompasses symptoms of decreased colonic motility or difficulty with the defecation process. As a broad definition, this can be inclusive of functional constipation (FC) or colonic inertia, obstructed defecation (OD), and irritable bowel syndrome-constipation type (IBS-CS). After excluding IBS-C, FC and OD diagnosis and management require a multidisciplinary approach often involving nutritionists, pelvic floor therapists, urogynecologists, and colon and rectal surgeons. Differentiating the presence or absence of each can direct therapy and prognosticate chances for improvement in this often complex combination of disorders.

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.

Position paper on transanal irrigation in chronic non-organic constipation

The practice of recto-colonic water irrigation to treat constipation has been used since ancient times with different, uncontrolled, and variably performing methods which have been considered interchangeably all alike. The use of better-performing devices with a standardized methodology is relatively recent, and the term Trans Anal Irrigation (TAI) defines a methodology performed with devices able to control the timing, volume, and pressure of the water introduced into the rectum and colon utilizing a catheter or a cone through the anus. Such practice has been implemented with favorable responses in patients with refractory chronic constipation secondary to neurological diseases. However, since the role of Trans Anal Irrigation as a therapeutic aid in chronic functional constipation and functional evacuation disorders is not yet fully clarified and standardized, a group of clinical investigators with recognized expertise in these clinical conditions intends to clarify the elements that characterize a TAI procedure that can benefit patients with functional constipation and functional defecation disorders defined according to the lastly updated Rome Diagnostic Criteria. Finally, the paper deals with adherence and practical implementation of TAI.

Difficult defecation in constipated patients: Diagnosis by minimally invasive diagnostic tests

BACKGROUND AND AIMS

Defecation Disorders (DD) are a frequent cause of refractory chronic constipation. DD diagnosis requires anorectal physiology testing. Our aim was to evaluate the accuracy and Odds Ratio (OR) of a straining question (SQ) and a digital rectal examination (DRE) augmented by abdomen palpation on predicting a DD diagnosis in refractory CC patients.

METHODS

Two hundred and thirty-eight constipated patients were enrolled. Patients underwent SQ, augmented DRE and balloon evacuation test before entering the study and after a 30-day fiber/laxative trial. All patients underwent anorectal manometry. OR and accuracy were calculated for SQ and augmented DRE for both dyssynergic defecation and inadequate propulsion.

RESULTS

"Anal Muscles" response was associated to both dyssynergic defecation and inadequate propulsion, with an OR of 13.6 and 5.85 and an accuracy of 78.5% and 66.4%, respectively. "Failed anal relaxation" on augmented DRE was associated with dyssynergic defecation, with an OR of 21.4 and an accuracy of 73.1%. "Failed abdominal contraction" on augmented DRE was associated with inadequate propulsion with an OR >100 and an accuracy of 97.1%.

CONCLUSIONS

Our data support screening constipated patients for DD by SQ and augmented DRE to improve management and appropriateness of referral to biofeedback.

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.

Effectiveness of a high fiber diet in improving constipation in patients with defecatory dyssynergy under treatment with anorrectal biofeedback. Exploratory, randomized clinical trial

INTRODUCTION

Fiber is the initial treatment in chronic functional constipation. However, its role in the group of patients with defecatory dyssynergy is not well established. The objective of the study is to evaluate the efficacy and safety of a high fiber diet in patients with defecatory dyssynergy in the treatment with anorectal biofeedback.

PATIENTS AND METHODS

An exploratory, randomized (1:1), double-blind, controlled «add-on» clinical trial was carried out in a reference center in Spain in patients with functional constipation and defecatory dyssynergy according to the ROMEIV criteria.

CONTROL GROUP

treatment with biofeedback and low-fiber diet (15-20g/day). Experimental group: treatment with biofeedback and high fiber diet (25-30g/day). Analyzed: responder (primary endpoint), patient whose defecatory dyssynergy had been corrected (>20% reduction in anal pressure during the defecation maneuver and normal balloon expulsion test); anorectal parameters (anal relaxation, reduced straining); safety (abdominal symptoms: flatulence, pain, borborygmus, bloating).

RESULTS

A total of 44 patients were randomized: 22 per group. The percentage of responders was 75% (15/20; 95%CI: 53 89%) control group and 70% (14/20; 95%CI: 48-85%) experimental group, P=.225. Differences in favor of the control group were only observed in abdominal symptoms: flatulence (P=.028), abdominal distension (P=.041) and digestive comfort (P=.043).

CONCLUSIONS

In patients with defecatory dyssynergy, a high-fiber diet not only does not improve the efficacy of anorectal biofeedback but is associated with a loss of improvement in abdominal symptoms.

Using a footstool does not aid simulated defecation in undifferentiated constipation: A randomized trial

INTRODUCTION

The use of a footstool has been advocated to optimize posture when sitting on the toilet and thus facilitate bowel evacuation. We aimed to assess the alterations in defecatory posture, and the changes in simulated defecation with use of a footstool in patients with constipation.

METHODS

Forty-one patients (female 93%, mean 52 year, SD 14 year) with constipation referred to a tertiary neurogastroenterology unit were enrolled. A bowel questionnaire, Hospital Anxiety and Depression Scale, and Rome questionnaire were administered prior to anorectal manometry. Each patient underwent three rectal balloon expulsion tests in randomized order with no footstool, a 7-inch, and a 9-inch footstool. Additional assessments included angle between spine and femur, and visual analogue scales assessing ease of evacuation, urge to defecate, and discomfort with expulsion.

KEY RESULTS

Defecatory posture was significantly altered by footstool use, with progressive narrowing of the angle between the spine and femur as footstool height increased (p < 0.001 for all comparisons). Compared with no footstool, the use of a footstool was not associated with a change in balloon expulsion time and there was no difference between the two footstool heights. Subjectively, no significant change was identified in any of the three perceptions of balloon expulsion between no footstool and footstool use.

CONCLUSIONS AND INFERENCES

Although the use of a footstool led to changes in defecatory posture, it did not improve subjective or objective measures of simulated defecation in patients with undifferentiated constipation. Therefore, the recommendation for its use during evacuation cannot be applied to all patients with constipation.

Defecatory Function Studies Using the Fecobionics Device Are Repeatable

BACKGROUND

Only limited data exist on repeatability of anorectal studies with the established physiological and clinical technologies for assessment of anorectal function. Fecobionics is a new multi-sensor simulated feces that provide data by integrating elements from current tests.

AIMS

To study repeatability of anorectal data obtained with the Fecobionics device.

METHODS

We assessed the database of Fecobionics studies to determine how many repeated studies were done. From a total of 260 Fecobionics studies, 19 subjects with repeated studies using approximately the same protocol and prototype were identified. Key pressure and bending parameters were assessed and the repeatability analyzed using Bland Altman plots. Furthermore, the inter- and intra-individual coefficient of variation (CV) were computed.

RESULTS

Fifteen subjects (5F/10 M) with repeated studies were normal subjects, three were patients with fecal incontinence and one subject suffered from chronic constipation. The main analysis was conducted on the cohort of normal subjects. The bias for 11 parameters were within the confidence interval, whereas two were slightly outside. The interindividual CV was lowest for the bend angle (10.1-10.7) and between 16.3 and 51.6 for the pressure parameters. The intra-individual CVs were approximately half of the inter-individual CVs, spanning from 9.7 to 27.6.

CONCLUSION

All data from normal subjects were within previously defined normality. The Fecobionics data showed acceptable repeatability with bias within the confidence limits for almost all parameters. The intra-individual CV was much lower than the inter-individual CV. Dedicated large-scale studies are warranted to evaluate the influence of age, sex, and disease on repeatability as well as comparing between technologies.

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.

Pelvic floor physical therapy in the treatment of chronic anal fissure (PAF trial): quality of life outcome

BACKGROUND

Chronic anal fissure is one of the most common anorectal diseases and is associated with reduced quality of life. The aim of this study was to investigate the effects of pelvic floor physical therapy on quality of life in patients with chronic anal fissure using the Short-Form 36 Health Survey (RAND-36).

METHODS

Adult patients, with chronic anal fissure and concomitant pelvic floor dysfunction, such as dyssynergia and increased pelvic floor muscle tone, were recruited at the Proctos Clinic in the Netherlands, between December 2018 and July 2021 and randomly assigned to an intervention group, receiving 8 weeks of pelvic floor physical therapy or assigned to a control group receiving postponed pelvic floor physical therapy (PAF trial). Quality of life and pain ratings were outcomes of the study and were measured at 8- and 20-week follow-up.

RESULTS

One hundred patients (50 women and 50 men, median age 44.6 years [range 19-68 years]), completed the RAND-36 questionnaire and visual analog (VAS) pain scale score at admission. A significant improvement was found at 20-week follow-up in all domains of the RAND-36; physical functioning, pain, health change (p < 0.001); physical role, vitality, general health, social functioning, emotional role, mental health (p < 0.05). VAS pain was significantly reduced at 8 weeks (mean estimated difference 1.98; 95% CI 1.55-2.42, p < 0.001) and remained significant at 20-week follow-up (p < 0.001). The difference between the groups as regards change in the mean pain intensity scores at 8 weeks was 2.48 (95% CI - 3.20 to - 1.75; p < 0.001). Compared to the reference values of the general Dutch population, the patients in our study with a chronic anal fissure and pelvic floor dysfunction reported an impaired quality of life in 8 of 9 domains of the RAND-36. After treatment, significant lower scores were found in 2 out of 9 domains.

CONCLUSIONS

The results of this study provide evidence that treatment by pelvic floor physical therapy improves quality of life and reduces pain, making it an important tool in management of chronic anal fissure and concomitant pelvic floor dysfunction.

Reproducibility of high-resolution manometry among healthy and constipated persons

BACKGROUND AND AIMS

Although high-resolution manometry (HR_ARM) is commonly used to diagnose defecatory disorders, its intraindividual day-to-day reproducibility is unknown. Since these measurements entail voluntary effort, this study aimed to evaluate the intraindividual day-to-day reproducibility of HR_ARM.

METHODS

In 22 healthy women (35 years [14] mean [SD]) and 53 constipated patients (42 years [13], 46 women), the rectal balloon expulsion time (BET), and anorectal pressures were measured with HR_ARM on 2 days separated by a median (interquartile range) of 15 days (11-53) in healthy and 40 days (8-75) in constipated patients. Anorectal pressures were evaluated at rest (20 s), during squeeze, and during evacuation. Rectal sensation was also evaluated in constipated patients. The agreement between both measurements was evaluated with Lin's concordance correlation coefficient (CCC) and other tests.

RESULTS

Among constipated patients, the anal resting (mean CCC [95%CI] 0.62 [0.43-0.76]) and squeeze pressures (CCC 0.65 [0.47-0.79]), rectoanal gradient during evacuation (CCC 0.42 [0.17-0.62]), and rectal sensory thresholds (CCC for urgency 0.72 [0.52-0.84]) were concordant. Between days 1 and 2, one or more outcomes, characterized as normal or abnormal, differed in 79% of constipated patients, i.e., anal resting and squeeze pressures, the gradient, and the rectal BET differed in, respectively, 25%, 19%, 36%, and 10% of constipated patients. The rectal BET was prolonged in three healthy persons (both days) and either on 1 day (six patients) or 2 days (33 patients) in constipated patients.

CONCLUSIONS

While HR_ARM variables and the BET are reproducible within healthy and constipated persons, the outcome on repeat testing differed in 79% of constipated patients.

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.

Clinical value of positive BET and pelvic floor dyssynergia in Chinese patients with functional defecation disorder

BACKGROUND

Functional defecation disorder (FDD) is a common subtype of functional constipation (FC). Balloon expulsion test (BET) and high resolution anorectal manometry (HR-ARM) are significant tools but their results are not always consistent.

AIMS

To investigate the characteristics of patients with positive BET and pelvic floor dyssynergia (PFD) and explore the value of both positive results in FDD diagnosis.

METHODS

We retrospectively diagnosed FC subtypes and enrolled FDD patients based on Rome-IV criteria. They underwent HR-ARM, BET and CTT tests. Then they were classified to two groups and further stratified by FDD subtypes. Validated questionnaires were applied to investigate patients' constipation, anxiety/depression and quality of life.

RESULTS

335 FDD patients were finally enrolled. They were classified into two groups according to whether BET and PFD were both positive (consistent or not). 84.48% showed consistent results. These patients had significantly higher anal residual pressure, lower anal relaxation rate, manometric defecation index (MDI) and a more negative rectoanal pressure gradient (RAPG) (Ps < .05). The specific distribution of FDD phenotypes in two groups showed significant difference (p = .021). Males suffered a more negative RAPG (p < .001) and age was correlated with anal relaxation rate (p < .001). A subset (177 individuals) was investigated with validated questionnaires. Scores for Defecation Symptoms, Physical Discomfort and GAD-7 score were significantly high in Consistent Group (Ps < .05). GAD-7 score was associated with Defecation Symptoms (p < .001) while anal residual pressure, GAD-7 and Defecation Symptoms score were linked to Physical Discomfort (Ps < .05). The diagnostic specificity and PPV for FDD rose significantly with positive BET and PFD.

CONCLUSION

FDD patients with positive BET and PFD suffered from severe defecation symptoms, anxiety and impaired QOL. Positive BET and PFD could be an ideal tool for screening FDD.

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.

Pelvic floor physical therapy in patients with chronic anal fissure: a randomized controlled trial

Background

A chronic anal fissure is a common, painful condition with great impact on daily life. The exact pathogenesis has not been fully elucidated and treatment varies. A large percentage of patients experience pelvic floor dysfunction (dyssynergia and increased pelvic floor muscle tone). The aim of our study was to investigate the effect of pelvic floor physical therapy in patients with chronic anal fissure.

Methods

Between December 2018 and July 2021, at the Proctos Clinic in the Netherlands, patients with chronic anal fissure and pelvic floor dysfunction were randomly assigned to an intervention group, receiving 8 weeks of pelvic floor physical therapy including electromyographic biofeedback or assigned to a control group receiving postponed pelvic floor physical therapy. The primary outcome was muscle tone at rest during electromyographic registration of the pelvic floor before and after pelvic floor physical therapy. Secondary outcomes contained healing of the fissure, pain ratings, improvement of pelvic floor function, and complaint reduction measured with a proctology-specific patient-reported outcome measurement. Endpoints were measured at 8- and 20-week follow-up.

Results

One hundred forty patients were included in the study, 68 men (48.6%) and 72 women (51.4%) with a mean age of 44.5 ± 11.1 (range 19–79) years. Mean resting electromyographic values of the pelvic floor in the intervention group significantly improved from pre- to post-treatment (p < 0.001) and relative to controls (mean estimated difference between groups − 1.88 µV; 95% CI, − 2.49 to − 1.27 (p < 0.001) at first follow-up and remained significant from baseline at 20-week follow-up (p < 0.001). The intervention group performed better compared to the control group on all secondary outcomes, i.e., healing of the fissure (55.7% of the patients vs 21.4% in control, pain ratings (p < 0.001), diminished dyssynergia (p < 0.001), complaint reduction (p < 0.001), and decrease of pelvic floor muscle tone (p < 0.05) at first follow-up.

Conclusions

The findings of this study provide strong evidence that pelvic floor physical therapy is effective in patients with chronic anal fissure and pelvic floor dysfunction and supports its recommendation as adjuvant treatment besides regular conservative treatment.

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.

Rectal Evacuation Disorders are Associated With Poor Bowel Preparation in Patients With Chronic Constipation: Results From Two Centers

INTRODUCTION

We evaluated factors that can predict the adequacy of bowel preparation in patients with chronic constipation undergoing colonoscopy.

MATERIALS AND METHODS

We identified patients with chronic constipation who underwent anorectal manometry and at least 1 colonoscopy at 2 tertiary referral centers from 2003 to 2019. We also identified a subgroup of patients who underwent colonic transit testing through radiopaque marker testing. We determined demographic, medical, and constipation-related factors associated with poor bowel preparation and their effect on standardized quality metrics using univariate and multivariate analyses.

RESULTS

We identified 274 patients with chronic constipation who underwent anorectal manometry testing. Both outlet dysfunction (prolonged balloon expulsion) and slow-transit constipation were associated with suboptimal bowel preparation. Outlet dysfunction was also associated with decreased cecal intubation rates, adenoma detection rates, and sessile serrated polyp detection rates. In multivariable analyses controlling for demographics and known factors associated with poor bowel preparation, outlet dysfunction was associated with an almost 3-fold odds of suboptimal bowel preparation [odds ratio (OR): 2.9; 95% confidence interval (CI): 1.6-5.1] and a 3-fold reduction in cecal intubation rates (OR: 0.3; 95% CI: 0.1-0.8). Among those with radiopaque marker colonic transit testing available, slow-transit constipation was associated with a >2-fold odds of suboptimal bowel preparation (OR: 2.2; 95% CI: 1.1-4.4).

CONCLUSIONS

Among a cohort of patients with chronic constipation undergoing colonoscopy, outlet dysfunction was associated with suboptimal bowel preparation and other quality metrics. Constipated patients with a rectal evacuation disorder may represent a subgroup of patients that could benefit from individualized strategies for better bowel preparation.

Pelvic floor biofeedback is an effective treatment for severe bloating in disorders of gut-brain interaction with outlet dysfunction

BACKGROUND

The pathophysiology of bloating is partially understood. We investigated in patients with disorders of gut-brain interaction (DGBI) the relationship between severity of bloating, abdominal girth changes and defecation pattern, and the efficacy of pelvic floor biofeedback treatment on bloating.

METHODS

Disorders of gut-brain interaction patients with severe bloating as the main complaint were prescribed 2 weeks dietary advice and underwent abdominal girth measurements. At the first visit, all patients underwent a questionnaire on the subjective improvement of bloating, a (0-100) VAS abdominal bloating, and abdominal girth measurement. Patients reporting inadequate bloating relief underwent a standardized balloon expulsion test. Furthermore, they were invited to undergo pelvic floor electromyography and biofeedback treatment previously used for constipation due to dyssynergic defecation. The primary outcome was bloating improvement on a 5-point Likert scale. The secondary outcomes were the effect of diet intervention and pelvic floor biofeedback treatment on bloating severity and quality of life changes as well as the effect of pelvic floor biofeedback treatment on BET and EMG on straining.

KEY RESULTS

One hundred and fifty six patients (129 F, 39.3 ± 11.7 mean age) completed the 2-week run-in period. 105 patients were diet non-responder and underwent balloon expulsion test, with the vast majority (64%) failing the test. Patients who scored higher bloating on VAS had a significant association with failed balloon expulsion test (adjusted B 0.4 [95% CI 10.8-25.7], p < 0.0001). 63% agreed to perform pelvic floor biofeedback treatment at Verona center, 54% became responders reporting fair or major improvement/cure (ITT analysis, McNemar test, p < 0.0001), and all of them showed a 50% decrease in bloating severity.

CONCLUSIONS AND INFERENCES

Disordered defecation is a prevalent etiology in DGBI patients with bloating unresponsive to conservative measures; pelvic floor biofeedback treatment to improve the defecation effort significantly relieved bloating (http://www.isrctn.com, ISRCTN17004079).

DIAGNOSIS AND MANAGEMENT OF CHRONIC IDIOPATHIC CONSTIPATION: A NARRATIVE REVIEW FROM A BRAZILIAN EXPERT TASK FORCE

ABSTRACT Background Chronic idiopathic constipation (CIC) is a condition that widely affects the global population, represents relevant healthcare resource utilization and costs, and impacts the individual’s well-being. Objective To review the consensus of expert societies and published guidelines on the diagnosis and treatment of CIC in adults, seeking to assist reasoning and decision-making for medical management of patients with CIC and provide a practical reference material. Methods A Brazilian medical task force searched the scientific literature in the following electronic databases: MEDLINE/PubMed, SciELO, EMBASE and Cochrane, using the following descriptors: chronic constipation, diagnosis, management of chronic constipation. In addition, a review of articles on the mechanism of action, safety, and efficacy of therapeutic options available in Brazil was carried out. Results The diagnostic approach and the understanding of the pathophysiology present in CIC are essential items to indicate the appropriate therapy and to understand the ecosystem of the patient’s needs. Conclusion CIC is a common condition in adults, occurring more frequently in the elderly and in women. Proper management is defined by detailed medical history and physical examination, together with appropriate therapeutics, regardless pharmacological or not, and depending on the best moment of indication. This way, the impact on quality of life is also optimized.

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.

Manometric parameters, when measured with the 3-dimensional high-definition anorectal manometry probe, poorly predict prolonged balloon expulsion time

BACKGROUND

There are little data evaluating the performance of the 3-dimensional high-definition anorectal manometry (3D-HDAM) system in the diagnosis of dyssynergic defecation. Physical properties of the thicker, rigid, 3D-HDAM probe may have implications on the measurements of anorectal pressures.

AIM

Our aim was to compare 3D-HDAM to balloon expulsion test and magnetic resonance (MR) defecography.

METHODS

Consecutive constipated patients referred for anorectal function testing at the Calgary Gut Motility Centre (Calgary, Canada) between 2014 and 2019 were assessed. All patients underwent anorectal manometry with the 3D-HDAM probe, and a subset underwent BET or MR defecography. Anorectal manometric variables were compared between patients who had normal and abnormal BET.

RESULTS

Over the study period, 81 patients underwent both 3D-HDAM and BET for symptoms of constipation. 52 patients expelled the balloon within 3 minutes. Patients with abnormal BET had significantly lower rectoanal pressure differential (RAPD) (-61 vs. -31 mmHg for normal BET, p = 0.03) and defecation index (0.29 vs. 0.56, p = 0.03). On logistic regression analysis, RAPD (OR: 0.99, 95% CI: 0.97-0.99, p = 0.03) remained a negative predictor of abnormal BET. On ROC analysis, RAPD had an AUC of 0.65. There was good agreement between dyssynergic patterns on 3D-HDAM and defecographic evidence of dyssynergia (sensitivity 80%, specificity 90%, PLR 9, NLR 0.22, accuracy 85%).

CONCLUSIONS

Manometric parameters, when measured with the 3D-HDAM probe, poorly predict prolonged balloon expulsion time. RAPD remains the best predictor of prolonged balloon expulsion time. The 3D-HDAM probe may not be the ideal tool to diagnose functional defecatory disorders.

New developments in defecatory studies based on biomechatronics

Introduction

Defecation is a complex process that is difficult to study and analyze directly. In anorectal disease conditions, the defecation process may be disturbed, resulting in symptoms including fecal incontinence and constipation. Current state-of-the-art technology measures various aspects of anorectal function but detailed analysis is impossible because they are stand-alone tests rather than an integrated multi-dimensional test.

Objectives

The need for physiologically-relevant and easy-to-use diagnostic tests for identifying underlying mechanisms is substantial. We aimed to advance the field with integrated technology for anorectal function assessment.

Methods

We developed a simulated stool named Fecobionics that integrates several tests to assess defecation pressures, dimensions, shape, orientation and bending during evacuation. A novelty is that pressures are measured in axial direction, i.e. in the direction of the trajectory. Using this novel tool, we present new analytical methods to calculate physiologically relevant parameters during expulsion in normal human subjects.

Results

Data are reported from 28 human subjects with progressively more advanced versions of Fecobionics. A new concept utilizes the rear-front pressure (preload-afterload) diagram for computation of novel defecation indices. Fecobionics obtained physiological data that cannot be obtained with current state-of-the-art technologies.

Conclusion

Fecobionics measures well known parameters such as expulsion time and pressures as well as new metrics including defecation indices. The study suggests that Fecobionics is effective in evaluation of key defecatory parameters and well positioned as an integrated technology for assessment of anorectal function and dysfunction.

A novel wireless, smartphone-based biofeedback training device for functional defecatory disorders: a pilot study

BACKGROUND

Functional defecatory disorders (FDDs) are highly prevalent around the world. Biofeedback is an effective treatment for FDDs. Traditionally, this treatment is performed by clinicians in a limited number of hospitals because of procedure-related expenses and a need for a dedicated procedure room. To make the biofeedback therapy more widely available, we have designed a novel wireless, smartphone-based biofeedback device, with the ultimate goal of performing the therapy at home. The aim of this pilot study was to investigate whether the developed device can be employed to treat patients with FDDs in a clinical setting, prior to employing it in a home setting.

METHODS

From March 2018 to July 2018, we performed the biofeedback therapy using the newly developed wireless, smartphone-based device in patients with FDDs 30 min daily during weekdays for 2 weeks. A Visual Analogue Scale (VAS) for bowel satisfaction, Patient Assessment of Constipation-Symptoms (PAC-SYM), Patient Assessment of Constipation Quality of Life (PAC-QOL), and a balloon expulsion test were assessed at baseline and after the therapy.

RESULTS

Thirteen patients were recruited and ten of them (mean age 70.3 ± 8.9 years, female:male ratio: 3:7) completed the study. Spontaneous bowel movements, complete spontaneous bowel movements, and VAS were all significantly increased after the therapy compared with baseline, respectively (6.5 ± 4.3 vs. 1.5 ± 2.2, p = 0.006; 3.1 ± 2.2 vs. 0.2 ± 0.6, p = 0.002; 49.5 ± 31.0 vs. 12.0 ± 9.2, p = 0.003). There was a significant decrease in the PAC-SYM and PAC-QoL after the biofeedback therapy (0.7 ± 0.6 vs. 1.4 ± 0.3, p = 0.001; 0.7 ± 0. 6 vs. 1.5 ± 0.4, p = 0.001). The therapy reduced the balloon expulsion time significantly (83.9 ± 68.8 s vs. 160.0 ± 36.7 s, p = 0.002). No obvious adverse events related to the procedure itself occurred.

CONCLUSIONS

Biofeedback training using the newly developed wireless, smartphone-based device is feasible in the clinic setting, and it seems to be a promising method for improving constipation and related symptoms in patients with FDDs. These findings could be used to develop a much-needed, home-based, suitably powered, randomized, controlled clinical trial.

Anorectal manometry to diagnose dyssynergic defecation: Systematic review and meta-analysis of diagnostic test accuracy

BACKGROUND

Chronic constipation is a common condition, and dyssynergic defecation underlies up to 40% of cases. Anorectal manometry is recommended to assess for dyssynergic defecation among chronically constipated patients but remains poorly standardized. We aimed to evaluate the diagnostic accuracy of anorectal manometry and determine optimal testing parameters.

METHODS

We performed a systematic review with meta-analysis of diagnostic test accuracy including cohort studies of chronically constipated patients and case-control studies of patients with dyssynergic defecation or healthy controls. Meta-analysis was performed to determine summary sensitivity, specificity, and area under the curve (AUC) with 95% confidence intervals (CI).

KEY RESULTS

A total of 15 studies comprising 2140 patients were included. Including all studies (estimating optimal diagnostic accuracy), the AUC was 0.78 [95% CI 0.72-0.82], summary sensitivity was 79% [61%-90%], and summary specificity was 64% [44%-79%] to diagnose dyssynergic defecation. In cohort studies only (estimating real-world diagnostic accuracy), the AUC was 0.72 [0.66-0.77], summary sensitivity was 86% [64%-95%], and summary specificity was 49% [30%-68%]. Employing three consecutive simulated defecation attempts improved sensitivity to 94%. A fourth simulated defecation maneuver with air insufflation may improve accuracy. Measuring anorectal pressures to identify complex dyssynergic patterns did not improve real-world diagnostic accuracy estimates over anal pressure measurement alone. Choice of manometry system did not impact diagnostic accuracy.

CONCLUSIONS & INFERENCES

Following the current iteration of the London consensus protocol (three simulated defecation attempts measuring anal relaxation), the role of anorectal manometry in evaluating dyssynergic defecation appears limited. Future iterations of this protocol may improve diagnostic accuracy.

Diagnosis of Functional Gastrointestinal Disorders and Choice of Treatment Regimen in Constipation Patients

Aim. A practical review of functional gastrointestinal disorder diagnosis in constipation patients and the rationale for opting treatment.

Key points. Functional constipation commonly afflicts different ages and negatively impacts the quality of life. The current diagnostic algorithm in chronic constipation includes the disease identification according to Rome Criteria IV, red-flag symptom detection and instrumental laboratory examination. Functional constipation is notably often associated with anorectal abnormalities that bear a diagnostic value to elaborate an apt treatment strategy. Anorectal manometry, rectal sensation and balloon expulsion tests are the well-studied and significant probing techniques for objective anorectal zone sensorimotor function assessment in patients with functional constipation. The article reviews modern diagnostic methods in functional defecation disorders.

Conclusion. The examination and treatment algorithms presented will help improve diagnosis and apply the most suitable management in a constipation-associated functional digestive pathology.

ACG Clinical Guidelines: Management of Benign Anorectal Disorders

Benign anorectal disorders of structure and function are common in clinical practice. These guidelines summarize the preferred approach to the evaluation and management of defecation disorders, proctalgia syndromes, hemorrhoids, anal fissures, and fecal incontinence in adults and represent the official practice recommendations of the American College of Gastroenterology. The scientific evidence for these guidelines was assessed using the Grading of Recommendations Assessment, Development and Evaluation process. When the evidence was not appropriate for Grading of Recommendations Assessment, Development and Evaluation, we used expert consensus to develop key concept statements. These guidelines should be considered as preferred but are not the only approaches to these conditions.

Diagnostics of functional disorders of the gastrointestinal tract in patients with constipation

The purpose of the review is to acquaint general practitioners, therapists, gastroenterologists with the possibilities of diagnosing functional disorders of the gastrointestinal tract associated with constipation, as well as to draw attention to the need for additional examination methods for a comprehensive assessment of functional disorders of the gastrointestinal tract in patients with constipation on pathogenesis.

Functional constipation is an urgent problem today due to its prevalence among different age groups, a negative impact on the quality of life, as well as the variability of the clinical forms of diseases associated with this symptom. The modern diagnostic algorithm for chronic constipation consists of several stages, including the identification of signs of the disease, according to the Rome criteria of the IV revision (2016), the identification of symptoms of “red flags” and laboratory and instrumental research. It should be borne in mind that functional constipation is often based on the pathology of the anorectal zone, which is an important factor in the diagnosis and development of further therapeutic strategies. The article provides an overview of modern and promising methods for diagnosing functional disorders of defecation, taking into account functional disorders of the anorectal zone associated with constipation.

Functional methods such as anorectal manometry, rectal sensory test and balloon expulsion test are the  most studied and obligatory tests for an objective assessment of the sensorimotor function of the anorectal zone. In Russia, these methods are used very little, which requires extensive familiarization of practitioners with the advantages of these techniques. Knowledge and application of the presented examination algorithms will help the clinician to increase the overall diagnostic efficiency and apply the most justified tactics of managing patients with functional pathology of the digestive system associated with constipation. 

Rectal Distension Increased the Rectoanal Gradient in Patients with Normal Rectal Sensory Function

BACKGROUND

Frequent observation of abnormal manometric patterns consistent with dyssynergia in healthy volunteers has warranted the need for reassessment of the current methods to enhance the diagnostic value of anorectal manometry in functional defecatory disorders. Whether rectal distention at simulated evacuation will affect anorectal pressure profile and increase rectoanal gradient is not known.

METHODS

One hundred and eight consecutive patients with chronic constipation, 93 females, median age 53 years (interquartile range: 40-65), were studied. Simulated evacuation was performed firstly with empty balloon and subsequently after balloon distention to 50 and 100 ml. Anorectal pressures were compared. We also performed subgroup analysis in relation to outcome of balloon expulsion test (BET). In addition, we studied the effect of rectal distension on the rectoanal pressure gradient with respect to rectal sensory function.

RESULTS

Rectal balloon distension at simulated evacuation improved rectoanal gradient and decreased the rate of dyssynergia during high-resolution anorectal manometry. In subgroup analysis, the increase in rectoanal gradient and correction of dyssynergia with rectal distension was limited to the patients who had normal BET and normal rectal sensory function. Rate of anal relaxation, residual anal pressures, and rectoanal gradient were significantly different between patients with and without normal BET at 50 ml of rectal distension. Rectoanal gradient recorded only after rectal distension, along with BMI and maximum tolerable volumes, could predict BET results independently in patients with chronic constipation.

CONCLUSIONS

Rectal distension during simulated evacuation will affect the anorectal pressure profile. Increase in rectoanal gradient and correction of dyssynergia was only significant in patients with normal rectal sensory function and normal BET.

Novel bionics developments in gastroenterology: fecobionics assessment of lower GI tract function

Biomechatronics (bionics) is an applied science that is interdisciplinary between biology and engineering (mechanical, electrical and electronics engineering). Biomechatronics covers a wide area and is probably best known in development of prosthetic limbs, vision aids, robotics and neuroscience. Although the gastrointestinal tract is difficult to study, it is particularly suited for a bionics approach as demonstrated by recent developments. Ingestible capsules that travel the tract and record physiological variables have been used in the clinic. Other examples include sacral nerve stimulators that seek to restore normal anorectal function. Recently, we developed a simulated stool termed fecobionics. It has the shape of normal stool and records a variety of parameters including pressures, bending (anorectal angle) and shape changes during colonic transit and defecation, i.e. it integrates several current tests. Fecobionics has been used to study defecation patterns in large animals as well as in humans (normal subjects and patient groups including patients with symptoms of obstructed defecation and fecal incontinence). Recently, it was applied in a canine colon model where it revealed patterns consistent with shallow waves originating from slow waves generated by the interstitial cells of Cajal. Furthermore, novel analysis such as the rear-front pressure (preload-afterload) diagram and quantification of defecation indices have been developed that enable mechanistic insight. This paper reviews the fecobionics technology and outlines perspectives for future applications.

Chronic constipation in adults: Contemporary perspectives and clinical challenges. 1: Epidemiology, diagnosis, clinical associations, pathophysiology and investigation

BACKGROUND

Chronic constipation is a prevalent disorder that affects patients' quality of life and consumes resources in healthcare systems worldwide. In clinical practice, it is still considered a challenge as clinicians frequently are unsure as to which treatments to use and when. Over a decade ago, a Neurogastroenterology & Motility journal supplement devoted to the investigation and management of constipation was published (2009; 21 (Suppl.2)). This included seven articles, disseminating all themes covered during a preceding 2-day meeting held in London, entitled "Current perspectives in chronic constipation: a scientific and clinical symposium." In October 2018, the 3rd London Masterclass, entitled "Contemporary management of constipation" was held, again over 2 days. All faculty members were invited to author two new review articles, which represent a collective synthesis of talks presented and discussions held during this meeting.

PURPOSE

This article represents the first of these reviews, addressing epidemiology, diagnosis, clinical associations, pathophysiology, and investigation. Clearly, not all aspects of the condition can be covered in adequate detail; hence, there is a focus on particular "hot topics" and themes that are of contemporary interest. The second review addresses management of chronic constipation, covering behavioral, conservative, medical, and surgical therapies.

Characterization of Patients With Obstructed Defecation and Slow Transit Constipation With a Simulated Stool

INTRODUCTION

Defecatory disorders including obstructed defecation (OD) are currently diagnosed using specialized investigations including anorectal manometry and the balloon expulsion test. Recently, we developed a simulated stool named Fecobionics that provides a novel type of pressure measurements and analysis. The aim was to study OD phenotypes compared with slow transit constipation (STC) patients and normal subjects (NS).

METHODS

Fecobionics expulsion parameters were assessed in an interventional study design. The Fecobionics device contained pressure sensors at the front, rear, and inside a bag. All constipation patients had colon transit study, defecography, anorectal manometry, and balloon expulsion test performed. The Fecobionics bag was distended in the rectum until desire-to-defecate in 26 OD compared with 8 STC patients and 10 NS. Rear-front pressures (preload-afterload parameters) and defecation indices (DIs) were compared between groups.

RESULTS

The Wexner constipation scoring system score was 13.8 ± 0.9 and 14.6 ± 1.5 in the OD and STC patients (P > 0.5). The median desire-to-defecate volume was 80 (quartiles 56-80), 60 (54-80), and 45 (23-60) mL in OD, STC, and NS, respectively (P < 0.01). The median expulsion duration was 37 (quartiles 15-120), 6 (3-11), and 11 (8-11) seconds for the 3 groups (P < 0.03). Fecobionics rear-front pressure diagrams demonstrated clockwise loops with distinct phenotype differences between OD and the other groups. Most DIs differed between OD and the other groups, especially those based on the anal afterload reflecting the nature of OD constipation. Several OD subtypes were identified.

DISCUSSION

Fecobionics obtained novel pressure phenotypes in OD patients. DIs showed pronounced differences between groups. Larger studies are needed on OD subtyping.