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Graphical abstract, Highlights • The physiology of defecation and the pathophysiology of defecation disorders have been described in numerous studies. • Disagreement exists between results of anorectal tests and they correlate poorly with symptoms. • We tested a novel wireless Fecobionics device, a simulated integrated stool in normal subjects. • Novel analysis of distensibility indices is presented based on preload-afterload diagrams and key parameters describing defecation are derived. • Fecobionics obtained reliable data under physiological conditions. The study suggests that Fecobionics is safe and effective in evaluation of key defecatory parameters. • Novel parameters were generated that may be important for subtyping of patients with anorectal disorders., 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.

Defecation is a complex process and up to 25% of the population suffer from symptoms of defecatory dysfunction. For functional testing, diagnostics, and therapy of anorectal disorders, it is important to know the optimal defecation position. is The aim of this study was to evaluate defecation pressure patterns in side lying, seated and squatting defecation positions in normal subjects using a simulated stool device called Fecobionics. The Fecobionics expulsion parameters were assessed in an interventional study design conducted from May 29 to December 9 2019. Subjects were invited to participate in the study through advertisement at The Chinese University of Hong Kong. The Fecobionics device consisted of a core containing pressure sensors at the front (caudal end) and rear (cranial end) and a polyester-urethane bag spanning most of the core length which also contained sensors. The Fecobionics bag was distended to 50 ml in the rectum of normal subjects (no present and past symptoms of defecatory disorders, no prior abdominal surgery, medication or chronic diseases). Studies were done in side lying (left lateral recumbent position), seated (hip flexed 90°) and squatting position (hip flexed 25°). Pressure endpoints including the rear-front pressure diagram and defecation indices were compared between positions. Twelve subjects (6 females/6 males, mean age 26.3 ± 2.6 [19.0–48.0] years) were included and underwent the planned procedures. The resting anal pressure for side lying and seated positions were 33.1 ± 4.1 cmH2O and 37.1 ± 4.0 cmH2O (p > 0.3). The anal squeeze pressure for side lying and seated positions were 98.4 ± 6.9 cmH2O and 142.3 ± 16.4 cmH2O (p 0.5). Rear-front pressure diagrams and distensibility indices demonstrated distinct differences in pressure patterns between the side lying position group and the other positions. The delay in expelling the Fecobionics device in the lying position was associated with dyssynergic pressure patterns on the device. Quantitative differences were not found between the seated and squatting position. Trial Registration http://www.clinicaltrials.gov Identifier: NCT03317938.

BACKGROUND Most patients who have undergone low anterior resection suffer from bowel dysfunction postoperatively. This condition is referred to as low anterior resection syndrome (LARS). The aim was to study defecatory patterns in LARS patients compared to a primary control group of fecal incontinence (FI) patients and normal subjects (NS) with the Fecobionics device. METHODS Fecobionics expulsion parameters were assessed in an interventional study design. The Fecobionics probe contained pressure sensors at the front, rear, and inside the bag. The bag was distended until urge sensation in rectum in 11 LARS patients (5F/6M, 63.2 ± 2.9 years), 11 FI subjects (7F/4M, 64.4 ± 2.5 years), and 11 NS (7F/4M, 63.6 ± 3.0 years). Defecation indices were computed from the Fecobionics data. All subjects had high-resolution anorectal manometry (ARM) and balloon expulsion test (BET) done. Symptoms were evaluated with LARS and Wexner scores. KEY RESULTS The LARS score in the LARS patients was 39.0 ± 0.6. The Wexner score in the LARS, FI, and NS groups was 14.2 ± 0.7, 10.1±1.0, and 0.0 ± 0.0 (p

Fecal continence is maintained by several mechanisms including anatomical factors, anorectal sensation, rectal compliance, stool consistency, anal muscle strength, mobility, and psychological factors. The homeostatic balance is easily disturbed, resulting in symptoms including fecal incontinence and constipation. Current technologies for assessment of anorectal function have limitations. Overlap exist between data obtained in different patient groups, and there is lack of correlation between measurements and symptoms. This review describes a novel technology named Fecobionics for assessment of anorectal physiology. Fecobionics is a simulated stool, capable of dynamic measurements of a variety of variables during defecation in a single examination. The data facilitate novel analysis of defecatory function as well as providing the foundation for modeling studies of anorectal behavior. The advanced analysis can enhance our physiological understanding of defecation and future interdisciplinary research for unraveling defecatory function, anorectal sensory-motor disorders, and symptoms. This is a step in the direction of improved diagnosis of anorectal diseases.

Fecal incontinence (FI) is characterized by involuntary loss of rectal content. Up to 9.5% of Americans younger than 70 years suffer from FI.1 The pathophysiology has many causes and is not well understood and diagnosed.

Background: Noncancer patients with life-limiting diseases often receive more intensive level of care in their final days of life, with more cardiopulmonary resuscitation performed and less do-not-resuscitate (DNR) orders in place. Nevertheless, death is still often a taboo across Chinese culture, and ethnic disparities could negatively affect DNR directives completion rates. Objectives: We aim to explore whether Chinese noncancer patients are willing to sign their own DNR directives in a palliative specialist clinic, under a multidisciplinary team approach Design: Retrospective chart review of all noncancer patients with life-limiting diseases referred to palliative specialist clinic at a tertiary hospital in Hong Kong over a 4-year period. Results: Over the study period, a total of 566 noncancer patients were seen, 119 of them completed their own DNR directives. Patients had a mean age of 74.9. Top 3 diagnoses were chronic renal failure (37%), congestive heart failure (16%), and motor neuron disease (11%). Forty-two percent of patients signed their DNR directives at first clinic attendance. Most Chinese patients (76.5%) invited family caregivers at DNR decision-making, especially for female gender (84.4% vs 69.1%; P = .047) and older (age >75) age group (86.2% vs 66.7%; P = .012). Of the 40 deceased patients, median time from signed directives to death was 5 months. Vast majority (95%) had their DNR directives being honored. Conclusion: Health-care workers should be sensitive toward the cultural influence during advance care planning. Role of family for ethnic Chinese remains crucial and professionals should respect this family oriented decision-making.

Background The mechanism of defaecation and continence is a complex process involving several factors. Identifying the cause of faecal incontinence is often difficult. Assessment of patients currently involve functional assessment with high-resolution anorectal manometry (HR-ARM) and anatomical assessment using Endoanal ultrasound (EAUS) scan, providing limited information. EndoFLIP (Functional Lumen Imaging Probe) allows additional assessment of anal canal distensibility.1 2 Aim To compare anal canal function using EndoFLIP between faecally incontinent patients (FI) and asymptomatic subjects (AS). Methods All subjects were assessed using HR-ARM, EAUS and EndoFLIP. Using the EndoFLIP, continuous ramp distension was carried out up to 5=bag vol. In second ramp distension, the 5=volume was maintained while the subjects were asked to squeeze their anus. Anal competence of the narrowest area of the anal canal was evaluated using three distinct parameters derived from the EndoFLIP data. Mann-Whitney’s U test was used for statistical analysis. Results Sixteen FI patients (2M/14F, Mean age 61.38 years, SEM +3.34) and 9 AS (3M/6F, Mean age 57.9 years, SEM +3.69) were assessed. The median yield pressure (the pressure when the diameter increased from baseline) was significantly lower in the FI group at 22.99 cmH20 (17.67–45.49 cmH20) compared to 55.95 cmH20 (36.56–64.82 cmH20) in asymptomatic subjects. There was no significant difference in the distensibility between the FI group 0.18 (0.17–0.35) mm/cmH20 compared to AS group 0.23 (0.12–0.39) mm/cmH20 calculated as the change in diameter divided by the change in distension pressure. The squeeze strength was significantly higher in the AS group 167.3 (62.0–270.8) mm.cmH20 compared to FI group 23.6 (8.1–86.1) mm.cmH20. Conclusions EndoFLIP demonstrated that FI patient‘s anal sphincters yielded at a lower pressure and had lower squeeze strength than in asymptomatic subjects, which may be clinically more relevant than squeeze pressures alone.

Background Defecation is a complex process. Defecatory disorders may be assessed using rectal balloon expulsion test (BET), high-resolution anorectal manometry (HR-ARM) and defecography. We have developed a Fecobionics device that integrates several current tests1 to assess pressures, orientation and bending all at once by the patient bedside. The Fecobionics probe is 10 cm long, 12 mm in diameter with 8 cm long inflatable bag and pressure sensors at each end. It contains two gyroscopes to measure the orientation and bending during defaecation. Aim To characterise physiological expulsion parameters in asymptomatic subjects using Fecobionics. Methods Fecobionics was inserted into the rectum and subjects were asked to sit on a commode. The bag was filled with fluid until subjects had the sensation to defaecate. Patients were asked to expel the Fecobionics. Time to expulsion, pressures and bending angles were assessed during the expulsion. This was compared to conventional 5=BET and HR-ARM. Results Eight subjects (6F/2M, 50 years (25–77)) were assessed. Defaecation urge was felt at 32±=. Five subjects expelled Fecobionics in one attempt. The expulsion time for Fecobionics and BET were 32.2±6.3 and 15.7±3.3 s respectively (p Conclusions It was possible to obtain reliable data under physiological conditions using Fecobionics. Five defecatory phases could be defined by the pressure signature. Orientation and bending could also be assessed.

INTRODUCTION: Defecation is a complex process that can be easily disturbed. Defecatory disorders may be diagnosed using specialized investigation, including anorectal manometry (ARM) and the balloon expulsion test (BET). Recently, we developed a simulated stool named Fecobionics that integrates several tests and assesses pressures, orientation, and bending during evacuation. The aim was to evaluate the feasibility and performance of Fecobionics for assessing defecatory physiology in normal subjects. METHODS: Physiological expulsion parameters were assessed in an interventional study design. The 10-cm-long Fecobionics probe contained pressure sensors at the front and rear and inside a bag and 2 motion processor units. The bag was distended in the rectum of 20 presumed normal subjects (15 female/5 male) until urge to defecate. ARM-BET was also performed. Three subjects used +2 minutes to evacuate BET, and 1 subject had a high fecal incontinence score. Therefore, the normal group consisted of 16 subjects (13 female/3 male aged 25–78 years). RESULTS: All subjects reported that Fecobionics evacuation was similar to normal defecation. Fecobionics expulsion pressure signatures demonstrated 5 phases, reflecting rectal pressure, anal relaxation, and anal passage. Preload-afterload loop diagrams demonstrated clockwise contraction cycles. The expulsion duration for BET and Fecobionics was 16 ± 2 and 23 ± 5 seconds (P > 0.2), respectively. The duration of the Fecobionics and BET expulsions was associated (P < 0.001). The change in bending of Fecobionics during defecation was 40 ± 3°. DISCUSSION: Fecobionics obtained reliable data under physiological conditions. Agreement was found for comparable variables between ARM-BET and Fecobionics but not for other variables. The study suggests that Fecobionics is safe and effective in evaluation of key defecatory parameters.

Objective The objective of the study was to evaluate the ability of a new prenatal diagnostic platform – prenatal BACs-on-Beads™ (BoBs™) in detecting mosaicism by comparison to quantitative fluorescence-polymerase chain reaction (QF-PCR). Methods A validation study of prenatal BoBs™ was firstly performed using 18 artificially constructing mosaic samples involving various aneuploidies and microdeletion conditions. Additionally, we compared the accuracy between prenatal BoBs™ and QF-PCR for 18 archived clinical mosaic cases and nine chromosomally abnormal cell lines with reference to conventional karyotype results. Results In the validation study, BoBs™ allowed the detection of mosaicism at a level of 20–40%. Among the clinical mosaic cases, 14/18 cases were within the detection of BoBs™, 8/14 (57.1%) could be identified by BoBs™ and 6/9 (66.7%) by QF-PCR, but 6/14 (42.9%) were missed by both tests. Three cases (16.7%) were detected by prenatal BoBs™ but missed by QF-PCR, whereas QF-PCR detected one case that was missed by BoBs™. The overall sensitivity of BoBs™ in detecting mosaicism is 44.4% (8/18), which is slightly higher than that of QF-PCR (33.3%; 6/18). Conclusion Prenatal BoBs™ has a sensitivity of 57.1% in the detection clinical mosaic cases. According to the validation test, mosaicism of 20% or greater is detectable by the BoBs™ assay. © 2012 John Wiley & Sons, Ltd.

Objective To assess the prevalence of discrepant results found between quantitative fluorescent polymerase chain reaction (QF-PCR) analysis on uncultured prenatal samples and karyotyping on long-term culture. Method Results of QF-PCR from 1932 amniotic fluid (AF) and 1132 chorionic villus (CV) samples collected from September 1999 to February 2008 were analyzed. Nature of discrepancies was categorized for normal or abnormal results from uncultured and cultured samples. Results A total of nine (0.8%) discrepant cases were found in the CV and six (0.3%) in AF samples. Three abnormal results involving trisomy 18 or mosaic trisomy 13 showed normal karyotype with one representing complete discordance. There were three QF-PCR reports with initial mosaic trisomy 21 and five cases involving sex chromosome aneuploidy showing complete trisomy 21 and 45,X, respectively, after long-term culture. Conclusions CV (0.8%) and AF (0.3%) samples showed discrepant results after culturing and 40% of discrepancy involved the sex chromosomes. QF-PCR on long-term culture was concordant with karyotyping results meaning that QF-PCR is technically sound. Discrepant PCR findings in uncultured prenatal samples likely arose from mosaicism or preferential cell culture. Limitations in abnormal QF-PCR results may be discussed with couples before further action. Copyright © 2009 John Wiley & Sons, Ltd.