High Definition Anorectal Manometry Research Articles

Three dimension high definition manometry evaluated postoperative anal canal functions in children with congenital anorectal malformations.

We aimed to evaluate the function of the reconstructed anal canal in postoperative anorectal malformations (ARMs) patients through three dimension (3D) high-definition anorectal manometry. From January 2015 to December 2019, 3D manometry was performed as a postoperative functional assessment of patients with ARMs divided into age subgroups based on the time of manometry. Manometric parameters, such as the length of the anorectal high-pressure zone (HPZ-length), the mean resting and squeeze pressure of HPZ (HPZ-rest and HPZ-sqze), recto-anal inhibitory reflex (RAIR), and strength distribution of the anal canal, were collected and compared with age-matched controls. Their functional outcomes were analyzed with SPSS 23.0 software for statistical analysis. 171 manometric measurements were performed on 142 postoperative patients (3 months∼15 years). The HPZ-rest in all patients was significantly lower than in age-matched controls (p < 0.05). HPZ-sqze was notably decreased in patients older than 4 years, whereas other age groups were comparable to controls (p < 0.05). The proportions of asymmetric strength distribution and negative RAIR were higher in ARMs patients. The type of anorectal malformations and lower HPZ-rest were the impact factors affecting postoperative functional outcomes. The majority of the ARMs patients had acceptable functional outcomes. 3D manometry can objectively assess the reconstructed anal canal function. The patients with fecal incontinence had a high proportion of extremely low HPZ-rest and HPZ-sqze, negative RAIR, and asymmetric strength distribution. The manometric details will help the clinicians explore the causes of defecation complications and guide further management.

Video-Based Deep Learning to Detect Dyssynergic Defecation with 3D High-Definition Anorectal Manometry.

We developed a deep learning algorithm to evaluate defecatory patterns to identify dyssynergic defecation using 3-dimensional high definition anal manometry (3D-HDAM). We developed a 3D-HDAM deep learning algorithm to evaluate for dyssynergia. Spatial-temporal data were extracted from consecutive 3D-HDAM studies performed between 2018 and 2020 at Dartmouth-Hitchcock Health. The technical procedure and gold standard definition of dyssynergia were based on the London consensus, adapted to the needs of 3D-HDAM technology. Three machine learning models were generated: (1) traditional machine learning informed by conventional anorectal function metrics, (2) deep learning, and (3) a hybrid approach. Diagnostic accuracy was evaluated using bootstrap sampling to calculate area-under-the-curve (AUC). To evaluate overfitting, models were validated by adding 502 simulated defecation maneuvers with diagnostic ambiguity. 302 3D-HDAM studies representing 1208 simulated defecation maneuvers were included (average age 55.2years; 80.5% women). The deep learning model had comparable diagnostic accuracy [AUC 0.91 (95% confidence interval 0.89-0.93)] to traditional [AUC 0.93(0.92-0.95)] and hybrid [AUC 0.96(0.94-0.97)] predictive models in training cohorts. However, the deep learning model handled ambiguous tests more cautiously than other models; the deep learning model was more likely to designate an ambiguous test as inconclusive [odds ratio 4.21(2.78-6.38)] versus traditional/hybrid approaches. Deep learning is capable of considering complex spatial-temporal information on 3D-HDAM technology. Future studies are needed to evaluate the clinical context of these preliminary findings.

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

We aimed to evaluate anorectal function of normal infants and children through three dimension high-definitionanorectal manometry (3D ARM) to fill the research blank in this area. From November 2014 to January 2019, 104 normal infants and children among patients who underwent 3D ARM were divided into four groups according to age (≤1month; >1month to ≤1year; >1year to ≤4years and >4years) and reviewed. The following parameters were performed: the length of anorectal high-pressure zone (HPZ), the resting pressure of HPZ (HPZ-rest), the squeezing pressure of HPZ (HPZ-sqze), recto-anal inhibitory reflex (RAIR), and pressure distribution of the anal canal. Graphpad Prism 7.0software was used for statistical analysis. HPZ, HPZ-rest, and HPZ-sqze increased with age. There were differences in HPZ-rest and HPZ-sqze between the groups (p<0.05). Sex had a significant effect on HPZ, but not on HPZ-rest and HPZ-sqze. The HPZ of males was higher than that of females among those ≤1month old (p<0.05). RAIR (-) was found in 17 patients (16%) for whom Hirschsprung's disease were excluded by biopsy, and these patients had regular defecation during follow-up. Most of the patients (85%) older than 1year had a symmetric anal pressure distribution during the contracting period (p<0.05). Anal canal function parameters gradually increased with age in normal infants and children which demonstrated the important role of age in evaluation, and these parameters can provide a reference for postoperative evaluation of anal canal function.

New Internet of Medical Things for Home-Based Treatment of Anorectal Disorders.

Home-based healthcare provides a viable and cost-effective method of delivery for resource- and labour-intensive therapies, such as rehabilitation therapies, including anorectal biofeedback. However, existing systems for home anorectal biofeedback are not able to monitor patient compliance or assess the quality of exercises performed, and as a result have yet to see wide spread clinical adoption. In this paper, we propose a new Internet of Medical Things (IoMT) system to provide home-based biofeedback therapy, facilitating remote monitoring by the physician. We discuss our user-centric design process and the proposed architecture, including a new sensing probe, mobile app, and cloud-based web application. A case study involving biofeedback training exercises was performed. Data from the IoMT was compared against the clinical standard, high-definition anorectal manometry. We demonstrated the feasibility of our proposed IoMT in providing anorectal pressure profiles equivalent to clinical manometry and its application for home-based anorectal biofeedback therapy.

Comparison of Anorectal Function as Measured with High-Resolution and High-Definition Anorectal Manometry

Introduction: Anorectal manometry (ARM) provides comprehensive assessment of pressure activity in the rectum and anal canal. Absolute pressure values might depend on the catheter used. Objective: Our aim was to compare the results obtained by different anorectal catheters in children with functional anorectal disorders. Methods: Children diagnosed with functional defecation disorders based on the Rome IV criteria were prospectively enrolled. ARM was performed in the supine position successively using 2 different probes in each patient in random order. Resting, squeeze pressures, and bear-down maneuver variables obtained by high-resolution (2-dimensional [2D]) and high-definition (3-dimensional [3D]) catheters were compared. Results: We prospectively included 100 children {mean age 7.5 [standard deviation (SD) ± 4.3] years; 62 boys}. Mean resting pressures were significantly higher when measured with the 3D than with the 2D catheter (71 [SD ± 19.4] vs. 65 [SD ± 20.1] mm Hg, respectively; p = 0.000). Intrarectal pressure measured by 3D and 2D catheters was similar (35 vs. 39 mm Hg, respectively; p = 0.761), but the percent of anal relaxation appeared to be higher for the 3D than for the 2D probe (12 vs. 5%, respectively; p = 0.002). Dyssynergic defecation (DD) was diagnosed in 41/71 patients (57.7%) using the 3D probe and in 51/71 children (71.8%) using the 2D probe (p = 0.044). Cohen’s kappa showed only fair agreement between the catheters (κ = 0.40) in diagnosis of DD. Conclusions: Our study demonstrated significantly different values of pressures obtained with different types of catheters. Normal ranges for conventional manometry cannot be applied to high-resolution systems, and results obtained by different types of manometry cannot be compared without adjustments (NCT02812823).

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

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. Our aim was to compare 3D-HDAM to balloon expulsion test and magnetic resonance (MR) defecography. 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. 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. -31mmHg 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%). 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.

Anorectal Disorders: An Update.

Anorectal disorders encompass structural, neuromuscular, and functional disorders. They are common, often distressing, and in some cases debilitating, and significantly add to the health care burden. They present with multiple, overlapping symptoms that can often obscure the underlying pathology and can pose significant diagnostic and management dilemmas. A meticulous history and comprehensive digital rectal examination can provide clarity on the diagnosis, appropriate testing, and management of these conditions. Today, with the development of sophisticated diagnostic tools such as high-resolution and high-definition (3-D) anorectal manometry, 3-D anal ultrasonography, magnetic resonance defecography and imaging, and neurophysiological tests such as translumbosacral anorectal magnetic stimulation, it is possible to more accurately define and characterize the underlying structural and functional abnormalities. In this review, we present a succinct update on the latest knowledge with regards to the pathophysiology, diagnosis and management of anal fissure, hemorrhoids, rectal prolapse, intussusception, rectocele, solitary rectal ulcer syndrome, levator ani syndrome, dyssynergic defecation and fecal incontinence.

Clinical and manometric characteristics of women with paradoxical puborectalis syndrome.

A subset of patients with functional defecation disorders have predominance of the puborectalis muscle (PRM) on three-dimensional high definition anorectal manometry (HDARM), known as paradoxical puborectalis syndrome (PPS). The aim of this study was to assess clinical and manometric differences between patients with and without PPS. A total of 227 women with functional defecation disorders undergoing HDARM between December 2012 and October 2016 at a single center were included in this study. All completed the Rome III constipation module and Pelvic Floor Distress Inventory 20 (PFDI-20). Eighty-seven out of 227 women had a 3D pressure topographic profile consistent with PPS. They had higher mean PDFI-20 scores for straining and incomplete evacuation symptoms than those without PPS. In addition, they demonstrated higher mean resting anal pressure, a more negative mean anorectal pressure differential, and a greater proportion with prolonged balloon expulsion test. These findings were more pronounced in a subgroup of 58 PPS patients with a distinct pattern of both posterior and posterolateral wall indentation. Among female patients with functional defecation disorders, those with PPS demonstrated clinical and manometric differences compared to those without PPS. These differences may be driven by predominant posterolateral wall indentation in a subgroup of PPS patients.

New Metrics in High-Resolution and High-Definition Anorectal Manometry.

To review recently published diagnostic methods that use high-resolution (HR-) or high-definition- (HD-) anorectal manometry (ARM) techniques. The integrated pressurized volume (IPV) is a new measure based on spatiotemporal plots obtained from HR-ARM. The IPV may be clinically useful for improving the prediction of abnormal balloon expulsion test in patients with constipation and for discriminating patients with anorectal disorders from asymptomatic controls. Combination of IPV parameters was superior to conventional manometric parameters in predicting the responsiveness to biofeedback therapy. Moreover, several novel parameters including the HR-ARM resting integral, HR-ARM squeeze profile, and anorectal asymmetry index may each be useful as predictive factors for identifying patients with fecal incontinence. HR- and HD-ARM are increasingly performed worldwide for evaluation of anorectal function. Here, we describe new metrics whose clinical significance has not been fully established. Further standardization and validation of these metrics could provide clinically important new information and could help improve our understanding of the pathophysiology of anorectal disorders.

Anal sphincter function as assessed by 3D high definition anorectal manometry

High resolution anorectal manometry has been developed over the past years, as well as 3D high definition manometry (HDARM). However, the clinical impact of the results obtained with these new technologies remains to be determined. We thus analyzed various HDARM parameters of anal sphincter function and tested their capacity to discriminate between patients with constipation and those with fecal incontinence. One hundred and fourteen consecutive patients underwent the same HDARM protocol (Medtronic), including 2 short duration voluntary anal contractions (5seconds) and 1 sustained (as long as possible) contraction. Various parameters evaluating the anal sphincter function were measured, based on automatic software analysis and Smartmouse™ item of the software; resting anal pressures, anal pressures and incremental pressures during voluntary squeeze and cough anal reflex. The ability of these parameters to discriminate between patients with fecal incontinence and chronic constipation was assessed using areas under the curves of ROC curves. All parameters were highly correlated. The most discriminant variable was found to be the mean anal pressure during sustained squeeze. The 3D lambda aspect of the anal sphincter during voluntary contraction was as frequently absent in both groups of patients (13% in patients with chronic constipation, versus 23% in those with fecal incontinence, P=0.18). There was a significant correlation between the fecal incontinence Wexner score and the voluntary anal contraction variables. Several parameters to assess the quality of voluntary anal contraction have been proposed. We observed with HDARM that the most discriminant parameter was the mean anal pressure during sustained squeeze. This may help to standardize and simplify HDARM protocols.

High-resolution and high-definition anorectal manometry: rediscovering anorectal function.

Anorectal motor and functional disorders are common among the general population. Anorectal manometry allows the study of anorectal motor activity both at rest and mimicking different physiological situations. High-resolution anorectal manometry (HR-ARM) and high-definition anorectal manometry (HD-ARM) are increasingly used in clinical practice. In comparison with the conventional technique, HR-ARM and HD-ARM catheters provide a higher number of recording points because of their many, closely packed circumferential sensors. This allows time-space visualization (topographic or 2-3-plane mode) as spatially continuous measurements are obtained by interpolation between near sensors. HR-ARM and HD-ARM allow a more standardized, reproducible technique, and a better assessment and understanding of the functional anatomy of the sphincter complex. Newer specific parameters are now being developed for use with these systems. They are being currently assessed by multiple research teams, and many of them remain unavailable for clinical practice as of today. However, they provide highly relevant information, which is now prompting a redefinition of anorectal anatomy and physiology. The goal of the present review was to describe the currently available HR-ARM and HD-ARM techniques, to discuss the normal values so far reported, and to analyze the newer parameters that may be assessed with these techniques, and which will likely be highly useful for clinical practice in the upcoming future.

Sa1640 - High Definition Anorectal Manometry Versus High Resolution Anorectal Manometry for Anorectal Disorders

Sa1640 - High Definition Anorectal Manometry Versus High Resolution Anorectal Manometry for Anorectal Disorders

45 - Relationships Between Anal Pressure Profiles Derived from High-Definition Anorectal Manometry and Results of Balloon Expulsion test in Patients with Chronic Constipation

45 - Relationships Between Anal Pressure Profiles Derived from High-Definition Anorectal Manometry and Results of Balloon Expulsion test in Patients with Chronic Constipation

Sa1632 - Anal Sphincter Function Evaluated by 3D High Definition Anorectal Manometry in Fecal Incontinence and Chronic Constipation Patients

Sa1632 - Anal Sphincter Function Evaluated by 3D High Definition Anorectal Manometry in Fecal Incontinence and Chronic Constipation Patients

Reproducibility of high-definition (3D) manometry and its agreement with high-resolution (2D) manometry in women with fecal incontinence.

While widely used in clinical practice, the reproducibility of high-definition anorectal manometry (HD-ARM) remains unclear. We evaluated the intra-individual reproducibility of HD-ARM and compared pressures measured with HD-ARM and high-resolution anorectal manometry (HR-ARM). Thirty-six women with fecal incontinence had an initial HD-ARM (HD-ARM1); on the same day, after randomization, 21 had a second (HD-ARM2). Sixteen women had a third (HD-ARM3) 4 weeks later. Twenty-five had also been evaluated by HR-ARM previously. Rectoanal pressures were assessed at rest, during squeeze and simulated evacuation. Concordance among pressures was assessed with Lin's concordance correlation coefficient (CCC). Anal resting and squeeze pressures measured with HD-ARM were reproducible on the same and different days; for average resting pressures of HD-ARM1 vs HD-ARM2, CCC=0.73 (95% confidence interval [CI]: 0.53-0.94), and for HD-ARM1 vs HD-ARM3, CCC=0.60 (95% CI: 0.28-0.93). For maximum squeeze pressures of HD-ARM1 vs HD-ARM2, CCC=0.86 (95% CI: 0.75-0.97), and for HD-ARM1 vs HD-ARM3, CCC=0.56 (95% CI: 0.21-0.91). The rectoanal gradient during evacuation was significantly concordant between HD-ARM1 and HD-ARM2 but not HD-ARM1 and HD-ARM3. Resting (CCC=0.38 [95% CI: 0.14-0.62]) and squeeze pressures (CCC=0.73 [95% CI: 0.57-0.89]) measured with HD-ARM1 and HR-ARM were also concordant. Among women with fecal incontinence, measurements with HD-ARM were reproducible on the same (anal resting and squeeze pressures and rectoanal gradient during evacuation) and different days (anal resting and squeeze pressures) and correlated with HR-ARM measurements. These findings support use of HD-ARM and HR-ARM for longitudinal assessments of anal resting and squeeze pressures.

A Predictive Model to Identify Patients With Fecal Incontinence Based on High-Definition Anorectal Manometry.

Three-dimensional high-definition anorectal manometry (3D-HDAM) is used to assess anal sphincter function; it determines profiles of regional pressure distribution along the length and circumference of the anal canal. There is no consensus, however, on the best way to analyze data from 3D-HDAM to distinguish healthy individuals from persons with sphincter dysfunction. We developed a computer analysis system to analyze 3D-HDAM data and to aid in the diagnosis and assessment of patients with fecal incontinence (FI). In a prospective study, we performed 3D-HDAM analysis of 24 asymptomatic healthy subjects (control subjects; all women; mean age, 39 ± 10 years) and 24 patients with symptoms of FI (all women; mean age, 58 ± 13 years). Patients completed a standardized questionnaire (FI severity index) to score the severity of FI symptoms. We developed and evaluated a robust prediction model to distinguish patients with FI from control subjects using linear discriminant, quadratic discriminant, and logistic regression analyses. In addition to collecting pressure information from the HDAM data, we assessed regional features based on shape characteristics and the anal sphincter pressure symmetry index. The combination of pressure values, anal sphincter area, and reflective symmetry values was identified in patients with FI versus control subjects with an area under the curve value of 1.0. In logistic regression analyses using different predictors, the model identified patients with FI with an area under the curve value of 0.96 (interquartile range, 0.22). In discriminant analysis, results were classified with a minimum error of 0.02, calculated using 10-fold cross-validation; different combinations of predictors produced median classification errors of 0.16 in linear discriminant analysis (interquartile range, 0.25) and 0.08 in quadratic discriminant analysis (interquartile range, 0.25). We developed and validated a novel prediction model to analyze 3D-HDAM data. This system can accurately distinguish patients with FI from control subjects.

How to Perform and Interpret a High-resolution Anorectal Manometry Test

High-resolution anorectal manometry (HR-ARM) and high-definition anorectal manometry (HD-ARM) catheters have closely spaced water-perfused or solid state circumferentially-oriented pressure sensors that provide much better spatiotemporal pressurization than non-high resolution catheters. This is a comprehensive review of HR-ARM and HD-ARM anorectal manometry catheter systems, the methods for conducting, analyzing, and interpreting HR-ARM and HD-ARM, and a comparison of HR-ARM with non-high resolution anorectal manometry. Compared to non-high resolution techniques, HR-ARM and HD-ARM studies take less time and are easier to interpret. However, HR-ARM and HD-ARM catheters are more expensive and fragile and have a shorter lifespan. Further studies are needed to refine our understanding of normal values and to rigorously evaluate the incremental clinical utility of HR-ARM or HD-ARM compared to non-high resolution manometry.

Sa1338 Concordance of Presenting Symptoms With 3D High Definition Anorectal Manometry: A Retrospective Study

Sa1338 Concordance of Presenting Symptoms With 3D High Definition Anorectal Manometry: A Retrospective Study

Accuracy and Reproducibility of High-definition Anorectal Manometry and Pressure Topography Analyses in Healthy Subjects

High-definition anorectal manometry (HDAM-3D) provides a topographic and 3-dimensional profile of anorectal pressure. We assessed anorectal sensorimotor function and the reproducibility of measurements made with HDAM-3D in healthy adults, and the accuracy of data analysis by its software. Anal sphincter pressures and rectal sensory thresholds were measured in 78 healthy subjects via placement of a 10-mm rigid probe, with 256 circumferentially arrayed pressure sensors, and a balloon in the rectum. The bearing down maneuver was assessed in a subset of 18 subjects. We compared data analyzed by an expert with findings from automated software analysis. Measurements made in a subset of 16 subjects, 2 weeks apart, were compared to determine reproducibility. Resting, squeezing, and sustained squeezing pressures were significantly higher in men than in women (P < .05); other parameters were similar. Desire and urgency to defecate were similar between men and women, but the maximal tolerable volume was significantly lower in women (P < .05). Older women (>50 years) had significantly lower resting (P < .01) and sustained squeeze pressures (P < .04). Dyssynergic patterns of defecation were observed in 12 of 18 subjects (67%) who attempted to defecate without the 60-mL rectal balloon distention and in 6 of 18 subjects (33%) with the 60-mL rectal balloon distention. Test-retest values correlated (r= 0.81), as did analyses made by an expert vs software analyses of data (r= 0.99). On the basis of HDAM-3D measurements in healthy adults, anal sphincter pressures are higher in men than in women, but sensory and other parameters are similar; older subjects have weaker sphincters. Many people were found to have dyssynergic patterns of defecation, which could be related to the probe or other technical issues, so this technique may not be suitable for assessing defecation patterns. Measurements made by HDAM-3D are reproducible, and data can be accurately analyzed by its software.

High Resolution and High Definition Anorectal Manometry and Pressure Topography: Diagnostic Advance or a New Kid on the Block?

The recent development of closely spaced circumferential solid state transducers has paved the way for novel technology that includes high resolution anorectal manometry and topography (HRAM) and 3-D high definition anorectal manometry (HDAM). These techniques are increasingly being used for the assessment of anorectal neuromuscular function. However, whether they constitute a diagnostic advantage or a mere refinement of an old technology is unknown. Unlike the traditional manometry that utilized 3 or 6 unidirectional sensors, the closely spaced circumferential arrangement facilitates superior spatiotemporal mapping of pressures at rest and during various dynamic maneuvers. HDAM can provide knowledge of the three muscles that govern the anal continence namely, the puborectalis, and the internal and external anal sphincters, and can show how they mediate the rectoanal inhibitory reflex and sensorimotor responses and the spatiotemporal orientation of these muscles. Also, anal sphincter defects can be mapped and readily detected using 3-D technology. Similarly, HRAM has facilitated confirmation and development of phenotypes of dyssynergic defecation. Recently, normative data have also been reported with HRAM and HDAM, together with the influence of age, gender, and test instructions. The greater yield of anatomical and functional information may supersede the limitations of costs, fragility, and shorter life-span associated with these new techniques. Thus, HDAM and HRAM are not just new gadgets but constitute a significant and novel diagnostic advance. However, more prospective studies are needed to better define anorectal disorders with these techniques and to confirm their superiority.