Intrarectal Pressure Research Articles

Lack of improvement in anorectal manometry parameters after implementation of a pelvic floor/anal sphincter biofeedback in persons with motor-incomplete spinal cord injury.

Effect of biofeedback on improving anorectal manometric parameters in incomplete spinal cord injury is unknown. A short-term biofeedback program investigated any effect on anorectal manometric parameters without correlation to bowel symptoms. This prospective uncontrolled interventional study comprised three study subject groups, Group 1: sensory/motor-complete American Spinal Injury Association Impairment Scale (AIS) A SCI (n = 13); Group 2 (biofeedback group): sensory incomplete AIS B SCI (n = 17) (n = 3), and motor-incomplete AIS C SCI (n = 8), and AIS D SCI (n = 6); and Group 3: able-bodied (AB) controls (n = 12). High-resolution anorectal manometry (HR-ARM) was applied to establish baseline characteristics in all subjects for anorectal pressure, volume, length of pressure zones, and duration of sphincter squeeze pressure. SCI participants with motor-incomplete SCI were enrolled in pelvic floor/anal sphincter bowel biofeedback training (2 × 6-week training periods comprised of two training sessions per week for 30-45 min per session). HR-ARM was also performed after each of the 6-week periods of biofeedback training. Compared to motor-complete or motor-incomplete SCI participants, AB subjects had higher mean intra-rectal pressure, maximal sphincteric pressure, residual anal pressure, recto-anal pressure gradient, and duration of squeeze (p < 0.05 for each of the endpoints). No significant difference was evident at baseline between the motor-complete and motor-incomplete SCI groups. In motor-incomplete SCI subjects, the pelvic floor/anal sphincter biofeedback protocol failed to improve HR-ARM parameters. Biofeedback training program did not improve anal manometric parameters in subjects with motor-incomplete or sensory-incomplete SCI. Biofeedback did not change physiology, and its effects on symptoms are unknown. Utility of biofeedback is limited in patients with incomplete spinal cord injury in terms of improving HR-ARM parameters.

Regional brain activation during rectal distention and attenuation with alosetron in a nonhuman primate model of irritable bowel syndrome.

Greater understanding of the mechanism that mediates visceral pain and hypersensitivity associated with irritable bowel syndrome (IBS) would facilitate the development of effective therapeutics to manage these symptoms. An objective marker associated with the underlying mechanisms of visceral pain and hypersensitivity could be used to guide therapeutic development. The current study examined brain activation evoked by rectal distention with functional magnetic resonance imaging (fMRI) in a cynomolgus macaque model of visceral hypersensitivity. Male, cynomolgus macaques underwent five four-week treatments of dextran sodium sulfate (DSS)-distilled water (DW), which induced mild-moderate colitis with remission during each treatment cycle. Balloon rectal distention (RD) was performed under anesthesia 14 weeks after the final DSS-DW treatment. Colonoscopy confirmed the absence of colitis prior to the start of RD. In naïve, untreated macaques, 10, 20 and 30 ml RD did not evoke brain activation. However, insular cortex/somatosensory II cortex and cerebellum were significantly activated in DSS-treated macaques at 20 and 30 ml rectal distention. Intra-rectal pressure after DSS treatment was not significantly different from that of naïve, untreated macaques, indicating lack of alteration of rectal functioning following DSS-treatment. Treatment with 5-HT3 receptor antagonist alosetron (p.o.) reduced distension-evoked brain activation and decreased intra-rectal pressure. The current findings demonstrated activation of brain regions to RD following DSS treatments which was not present in naïve macaques, suggesting visceral hypersensitivity. Brain activation in turn was reduced by alosetron, which could underlie the analgesic effect alosetron in IBS patients.

Endoscopic resection of the rectal mucosal bridge after surgery for Hirschsprung's disease

A 16-year-old young man was referred to our department because he had experienced severe lower abdominal pain during every defecation since childhood. He had undergone partial enterectomy and subtotal colectomy for Hirschsprung's disease right after birth. Colonoscopy revealed a thick rectal mucosal bridge at the anastomosis of the rectum to the jejunum (A, B). We suspected that the mucosal bridge disturbed stretching of the rectum and that increased intrarectal pressure by an accumulation of stool would cause severe abdominal pain.

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).

Postural Sensorimotor Control on Anorectal Pressures and Pelvic Floor Muscle Tone and Strength: Effects of a Single 5P® LOGSURF Session. A Cross-Sectional Preliminary Study.

Pelvic floor dysfunction (PFD) is a functional condition present most frequently in women. Despite pelvic floor muscle training being considered by the International Continence Society (ICS) as the first-line treatment in uncomplicated urinary incontinence, other more comprehensive postural methods as 5P® LOGSURF have emerged. This preliminary cross-sectional study explores the effects of a single 5P® LOGSURF session on pelvic floor muscle (PFM) tone and strength (MVC), resting anal tone, intrarectal pressure, and deep abdominal muscles activation. Thirty women were included (11 without PFD and 19 with PFD). Primary outcome measures were PFM tone, PFM MVC and resting anal tone and secondary measures outcomes were intrarectal pressure and deep abdominal activation. All outcome measures were collected before, throughout and after a single 30′ 5P® LOGSURF session. The findings from this study suggest that PFM tone (PFD group: p = 0.09, d = 0.72; non-PFD group: p = 0.003, d = 0.49) and PFM MVC (PFD group: p = 0.016; non-PFD group: p = 0.005) decreased in both groups after a single 5P® LOGSURF session, with a medium effect size for women with PFD. Contrarily, deep abdominal muscle MVC increased (PFD group: p < 0.001; non-PFD group: p = 0.03). Intrarectal pressure and resting anal tone decreased in both groups throughout the session. These results suggest that 5P® LOGSURF method may be interesting if is performed by women with mild symptoms of PFD or healthy women to achieve a decrease in PFM tone in women who manifested pain to intracavitary techniques or practices. Further research with higher sample sizes and long-term are necessary for generalizing.

Study on the characteristics of intestinal motility of constipation in patients with Parkinson's disease.

BACKGROUNDConstipation is one of the most important nonmotor symptoms in Parkinson's disease (PD) patients, and constipation of different severities is closely related to the pathogenesis of PD. PD with constipation (PDC) is considered a unique type of constipation, but its mechanism of formation and factors affecting its severity have been less reported. Understanding the gastrointestinal motility characteristics and constipation classification of PDC patients is essential to guide the treatment of PDC. In this study, the colonic transit test and high-resolution anorectal manometry were used to identify the intestinal motility of PDC to provide a basis for the treatment of PDC.AIMTo investigate the clinical classification of PDC, to clarify its characteristics of colonic motility and rectal anal canal pressure, and to provide a basis for further research on the pathogenesis of PDC.METHODSTwenty PDC patients and 20 patients with functional constipation (FC) who were treated at Xuanwu Hospital of Capital Medical University from August 6, 2018 to December 2, 2019 were included. A colonic transit test and high-resolution anorectal manometry were performed to compare the differences in colonic transit time, rectal anal canal pressure, and constipation classification between the two groups. RESULTSThere were no statistically significant differences in sex, age, body mass index, or duration of constipation between the two groups. It was found that more patients in the PDC group exhibited difficulty in defecating than in the FC group, and the difference was statistically significant. The rectal resting pressure, anal sphincter resting pressure, intrarectal pressure, and anal relaxation rate in the PDC group were significantly lower than those in the FC group. The proportion of paradoxical contractions in the PDC group was significantly higher than that in the FC group. There was a statistically significant difference in the type composition ratio of defecatory disorders between the two groups (P < 0.05). The left colonic transit time, rectosigmoid colonic transit time (RSCTT), and total colonic transit time were prolonged in PDC and FC patients compared to normal values. The patients with FC had a significantly longer right colonic transit time and a significantly shorter RSCTT than patients with PDC (P < 0.05). Mixed constipation predominated in PDC patients and FC patients, and no significant difference was observed. CONCLUSIONPatients with PDC and FC have severe functional dysmotility of the colon and rectum, but there are certain differences in segmental colonic transit time and rectal anal canal pressure between the two groups.

Good urodynamic practice: Pressure signal quality immediately after catheter insertion for cystometry with a water-filled pressure transducer system and its relevance for the ICS zero procedure.

AimThis study aims to evaluate the intracorporeal pressures immediately after the insertion of the catheters for urodynamic testing with a water‐filled urodynamic pressure transducer system to determine the relevance of the International Continence Society (ICS) zeroing principles.MethodsHere, a retrospective analysis of a random series of urodynamic recordings is performed. The initial pressures, immediately after the insertion of the catheters, have been compared with the pressures after some milliliters of filling and flushing away of the gel, used with insertion, and/or the mucus and debris from the inserted catheters. Differences of initially recorded intravesical and intrarectal pressures from those after flushing and filling are analyzed and associated with the ICS standard practice of zeroing.ResultsStatistically and clinically significant differences between the initial pressures and the pressures after filling and flushing are observed, with nonphysiological initial pressures in 62% of the studies. Some filling (20 ml or more in the bladder) and flushing of the pressure channels resulted in the registration of physiological pressures and synchronous response from both lines on abdominal pressure increases.ConclusionsThe pressure signal quality of a water‐filled urodynamic system immediately after catheter insertion is low with inaccurately displayed pressure values, but it changes to normal after flushing the pressure channels and some filling. Rezeroing of the intracorporeal pressures immediately after catheter insertion for cystometry is the inappropriate correction procedure that misleadingly modifies the false initial pressures, resulting in ongoing unrealistic urodynamic study pressures.

Dyssynergic Defecation and Anal Sphincter Disorders in Children in High-Resolution Anorectal Manometry Investigation.

Dyssynergic defecation is a common disorder in children with functional constipation (FC) because of relaxation disorders of the sphincter apparatus and intra-rectal pressure during defecation. The aim of the study was to determine frequency and type of dyssynergic defecation and to assess pressure in the anal canal poles during simulated evacuation and function of puborectalis muscle in defecation in children with FC. Three-dimensional (3D) high-resolution anorectal manometries (3D HRAM) were performed in 131 children with FC. In the manometric test, resting pressure measurements were assessed in 4 measuring poles of the anal canal. One hundred thirty-one children ages 5 to 17 years (mean age 10.2; SD ± 3.8; median 10) were involved in the study (69 girls and 62 boys). Dyssynergic defecation was shown in 106/131 (80.9%) examined children. A statistically significant difference between the age of examined children (P < 0.02) and intrarectal pressures at the anal canal measuring points (left P < 0.009, right P < 0.005, anterior P < 0.01) was found. Correlation between the residual pressure values in lateral anal canal measurement poles and intrarectal pressure was demonstrated in all types of dyssynergy (left: r = 0.69, P < 0.0005; right: r = 0.74, P < 0.0005). In a group of 53/131 (40.5%) children, 3D HRAM showed a rectal pressure increase during simulated defecation, because of the dysfunction of the puborectalis muscle. The increase in sphincter pressure in lateral and posterior poles in I and II types of dyssynergia and in lateral poles in other types of dyssynergia may depend on relaxation disorders of the puborectalis muscle during defecation.

SPARC: Wireless Fecobionics Device in dogs

ObjectiveWe developed a novel wireless device (Fecobionics) for mapping colonic and anorectal neuromuscular function. Fecobionics measures pressures, cross‐sectional areas and bending of the device and transmits data wireless to a receiver unit outside the body (figure 1). This study evaluated the safety of the device in dogs relative to the predicate THD SensyProbe device for biofeedback. Furthermore, physiological data were obtained with Fecobionics.MethodsTwelve male Mongrel dogs with 25kg body weight were assigned into two groups: Fecobionics group and predicate control group (N=6 of each). Fecobionics and the predicate device were transanally inserted into rectum. Further, each group was divided into two sub‐groups: The acute group in which the animals were euthanized immediately after the evacuation of the device, and the chronic group in which the animals were terminated after 2 weeks. The animals were monitored daily. Tissue from different colon segments and anorectum were collected after the dogs were euthanized. HE staining and immunofluorescence staining were performed.ResultsAll procedures were performed successfully without complications. All chronic animals showed normal food intake and behavior after the procedure. Wireless transmission of Fecobionics data were without significant data loss or data error. Fecobionics studies demonstrated defecation pressures in the range 60–100cmH2O. The bending of the device, representative of the anorectal angle, was less than 30 degrees. The shape of the bag was obtained from the serial cross‐sectional area measurements. The shape of Fecobionics was cylindrical in rectum and changed to hourglass shape when it passed through the anal canal. No signs of inflammation were identified in the tissue sections examined histologically or immunohistochemically (macrophages and caspase‐3) in both Fecobionics and control groups.ConclusionsWireless Fecobionics is as safe as the predicate device, without inducing macro‐ or microscopic changes or inflammatory status of anorectal muscle. Novel physiological data were obtained. Dogs seems not to have an anorectal angle like humans, which makes defecatory efficacy more dependent on intrarectal pressure and anal sphincter relaxation compared to humans.Support or Funding InformationFundingNIH SPARC OT2OD025308The Fecobionics device (left), the wireless receiver (middle) and the data collection device (right).Figure 1

508 Relationship of Patient Factors to High Resolution Anorectal Manometry Findings in Chronic Constipation

INTRODUCTION: High resolution anorectal manometry (HRARM) is used to evaluate patients with chronic constipation by assessing anorectal sensory and motor dysfunction. Despite the growth of HRARM, there is still little known about the patient factors that are associated with manometric diagnoses of dyssynergic defecation (DD) and its subtypes Type I – IV. The aims of this study are: 1) to characterize the abnormalities on HRARM in patients with chronic constipation seen at our center; and 2) to correlate patient factors (demographics and symptoms) to abnormalities identified on HRARM. METHODS: HRARM of consecutive patients being evaluated for chronic constipation between July 2018 and February 2019 were included. Patients completed a questionnaire describing symptoms related to their bowel movements. HRARM was performed using ManoScanTMand analyzed using ManoViewTM software (Medtronic, Shoreview, MN). Results are expressed as mean±SD or percentages. Metrics were compared using ANOVA or chi square tests, as appropriate. RESULTS: Of 170 patients included in the study, 63 had Type 1 DD, 24 had Type 2 DD, 16 had Type 3 DD, 17 had Type 4 DD, and 50 patients had a non-dyssynergic defecation pattern (Figure 1). Demographics: Patients with Type 3 DD were younger (P = 0.02) and had a higher BMI (P = 0.07), while patients with Type 1 DD were older (P = 0.02) (Table 1). Additionally, patients with Type 1 or Type 2 DD were more likely to be men (P = 0.02); a majority (29 of 36, 81%) of men had either Type 1 or Type 2 DD. Symptoms: Patients with Type 1 DD less frequently had 2 or less bowel movements per week (P = 0.02). Several other symptoms trended towards a difference such as improvement of abdominal discomfort with bowel movement (P = 0.15) and blockage sensation (P = 0.13). Manometric profile: Patients with Type 2 and Type 4 DD had lower intrarectal pressure compared to Type 1 DD, Type 3 DD, and non-DD patients (P &lt; 0.001). CONCLUSION: Type 1 dyssynergic defecation is the most common form of anorectal dysfunction seen in patients with chronic constipation. Age and sex distribution differed between the dyssynergic defecation subtypes and normal HRARM populations. However, the symptom profile between these groups is largely the same. Thus, HRARM remains an important tool in differentiating dyssynergic defecation from other causes of chronic constipation.

469 Efficacy of Biofeedback Therapy for Dyssynergic Constipation Among Elderly Patients

INTRODUCTION: The prevalence of constipation among older adults is estimated to be as high as 40% (Melton et al, 1996). Dyssynergic defecation (DD) is an important cause of constipation for a large proportion of these patients. While biofeedback (BFB) therapy has been shown to be highly effective in correcting DD, it involves operant conditioning which requires learning new techniques and few studies have looked at how older adults respond to BFB. METHODS: This is a retrospective analysis of age 65+ patients enrolled in BFB for DD between 2015 to 2018 at a tertiary referral motility program. For patients that had greater than two sessions, survey and high resolution anorectal manometry (HR-ARM) data were collected at baseline and during each BFB visit. 58 patients met criteria. ARM is utilized with sensors in the rectum and anal canal. Stool retention simulation is performed involving inflation of a rectal balloon during the BFB sessions. RESULTS: Patients described improvement in several meaningful clinical outcomes. The overall median education level was completed high school and some college. Mean global bowel satisfaction on a scale of 1 (very dissatisfied) to 10 (very satisfied) showed a statistically significant increase, 2.77 to 5.01 with BFB (P ≤ 0.0001). In addition, the important symptom of a feeling of incomplete evacuation after stooling decreased from 95% down to 24% (P = 0.0025). Most significantly, 79% of the age 65+ patients showed resolution of their dysyynergia on HR-ARM at their final session (P = 0.0006). The defecation index (DI), intrarectal pressure divided by intra-anal pressure during simulated defecation, also trended towards improvement (0.564 to 0.681, P = 0.12). In terms of types of dyssynergia (1 through 4), subjects with defects in both propulsion and paradoxical contraction of sphincter muscles during defecation, i.e. type 2 dyssynergia, showed the most substantial objective gains in defecation index, with an average increase of 0.486, P-value 0.01 (2 vs 1) and 0.02 (2 vs 3). CONCLUSION: Biofeedback for DD shows meaningful improvement in both patient reported outcomes and objective manometric parameters in older adults. This is an important finding because our data supports the efficacy of BFB among older adults, across all levels of education. Given the profound burden of constipation with DD in older adults, we propose biofeedback therapy continue to be given strong consideration as first line therapy for this population.

222 Biofeedback Therapy for Dyssynergic Defecation Is Effective Among Patients With Opioid Exacerbated Constipation

INTRODUCTION: Up to 90% of patients on opioids complain of constipation (Wurzelmann et al, 2007). Among opioid users, causes of chronic constipation can be multifactorial and related to other contributing factors such as dyssynergic defecation (DD). Biofeedback (BFB) therapy has been shown to be effective in patients with DD, but has not been studied among those who have DD and are on opioids. METHODS: This study was a retrospective analysis of patients enrolled in BFB for DD between 2015 to 2018 at a tertiary referral motility program. For patients that had greater than two sessions, survey and high resolution anorectal manometry (HR-ARM) data were collected at baseline and during each BFB visit. RESULTS: 117 patients met criteria, of these, 20 patients were on active opioid therapy. Compared to those not on narcotic analgesics, opioids users were more likely to have a higher baseline defecation index (DI), intrarectal pressure divided by intra-anal pressure during simulated defecation (0.669 vs. 0.456 P &lt; 0.0007). Decreased rectal sensation at baseline was seen in 20% of opiate patients and 19% of those not on opioids (P = 1.0). Opiate users compared to those not on narcotic analgesics also had a lower baseline health rating on the SF-36 scale (3.9 vs. 3.4 1-5 Likert scale P = 0.05) and were more likely to withdraw before completing a full course of BFB (P &lt; 0.01). On stool diary, opiate users did not report a significant improvement in global bowel satisfaction rating (2.9 to 4.2, 10-point Likert scale P = 0.13), in contrast to non-opiate users who did repot improvement (2.7 to 4.9, P &lt; 0.0001). Opiate users, however, had a significant decrease in number of stooling medications used (1.8 to 1.1 P = 0.04). On HR-ARM, there was a greater change in DI among non-opiate users as compared to opiate users. After BFB, opiate users effectively normalized their dyssynergia (79% improved) (P &lt; 0.0001). Non-opiate users also showed significant improvement in normalizing their dyssynergia (74%) (P &lt; 0.0001). CONCLUSION: Patients with opioid exacerbated constipation and DD showed meaningful clinical improvement in both subjective outcomes as well as manometric parameters. While they had lower baseline health rating at the outset and did not report significant improvement in global bowel satisfaction rating, unlike the non-opioid users, they nevertheless clearly benefited from BFB therapy. Overall, this data suggests that opioid users with DD may benefit from enrollment in BFB therapy.

Atropine Premedication Facilitates Ultrasound-Guided Reduction by Saline Enema in Children With Intussusception.

Background and Objective: Intussusception is the most frequent pediatric abdominal emergency. Intestinal spasm, ischemia, necrosis and even death may occur without prompt diagnosis and treatment. The ultrasound-guided reduction by saline enema is a preferred non-surgical procedure for intussusception. Muscular relaxants can relieve the intestinal spasm and edema by relaxing the intestinal smooth muscle, which may facilitate the treatment of intussusception. However, controversy persists on whether muscular relaxants are effective in the procedure. Therefore, the purpose of our study was to assess the efficacy of atropine known as a muscular relaxant in ultrasound-guided reduction by saline enema in children with intussusception.Methods: All patients with intussusception diagnosed and treated in our department from July 2016 to February 2018 were included. Four hundred and thirty-seven children were enrolled and randomly divided into two groups: an atropine group and a control group. Intramuscular atropine at a dose of 0.02 mg per kilogram of body weight was administrated 15 min before ultrasound-guided reduction by saline enema in the atropine group. In the control group, the ultrasound-guided reduction was performed without using any muscular relaxants. The success rate, duration of the reduction, volume of saline, maximum intra-rectal pressure and complications were recorded and compared between the two groups.Results: The success rate was 95.9% (212 out of 221) and 94.9% (205 out of 216) in the atropine group and the control group, respectively. No significant difference was observed in the success rate between the two groups (P > 0.05). The duration of reduction was significantly lower in the atropine group than in the control group (P < 0.01). The volume of saline was also significantly lower in the atropine group than in the control group (P < 0.05). The maximum intra-rectal pressure showed no difference between the two groups (P > 0.05).Conclusion: Atropine premedication can facilitate ultrasound-guided reduction by saline enema in children with intussusception, by reducing the duration of reduction and the volume of saline in the procedure.

A biomechanical model of the human defecatory system to investigate mechanisms of continence.

This article presents a method to fabricate, measure and control a physical simulation of the human defecatory system to investigate individual and combined effects of anorectal angle and sphincter pressure on continence. To illustrate the capabilities and clinical relevance of the work, the influence of a passive-assistive artificial anal sphincter (FENIXTM) is evaluated. A model rectum and associated soft tissues, based on geometry from an anonymised computed tomography dataset, was fabricated from silicone and showed behavioural realism to the biological system and ex vivo tissue. Simulated stool matter with similar rheological properties to human faeces was developed. Instrumentation and control hardware were used to regulate injection of simulated stool into the system, automate balloon catheter movement through the anal canal, define the anorectal angle and monitor stool flow rate, intra-rectal pressure, anal canal pressure and puborectalis force. Studies were conducted to examine the response of anorectal angles at 80°, 90° and 100° with simulated stool. Tests were then repeated with the inclusion of a FENIX device. Stool leakage was reduced as the anorectal angle became more acute. Conversely, intra-rectal pressure increased. Overall inclusion of the FENIX reduced faecal leakage, while combined effects of the FENIX and an acute anorectal angle showed the greatest resistance to faecal leakage. These data demonstrate that the anorectal angle and sphincter pressure are fundamental in maintaining continence. Furthermore, it demonstrates that use of the FENIX can increase resistance to faecal leakage and reduce anorectal angles required to maintain continence. Physical simulation of the defecatory system is an insightful tool to better understand, in a quantitative manner, the effects of the anorectal angle and sphincter pressure on continence. This work is valuable in helping improve our understanding of the physical behaviour of the continence mechanism and facilitating improved technologies to treat severe faecal incontinence.

Effect of biofeedback therapy on anorectal physiological parameters among patients with fecal evacuation disorder.

Though biofeedback therapy is often effective in patients with fecal evacuation disorder (FED), a common cause of chronic constipation (CC) in tertiary practice, data on anorectal physiological parameters following it are scanty. Consecutive patients with FED with CC diagnosed by abnormalities in at least two of the three tests (anorectal manometry, defecography, and balloon expulsion test [BET]) undergoing biofeedback (two sessions per day, 30min each, for 2weeks) during a 3-year period were analyzed. Clinical evaluation, anorectal manometry (ARM), and BET were performed at the beginning and after biofeedback. Incomplete evacuation 42/43 (98%), straining 40/43 (93%), and feeling of outlet obstruction 35/43 (81%) were the most common symptoms among these 43 patients (median age 44years, range 18-76, 30 [71%] male). All the three tests (defecography, BET, and ARM) were abnormal in 17 (40%) patients and the others had two abnormal tests. Improvement in physiological parameters was noted following biofeedback (median residual anal pressure during defecation 99mmHg (range 52-148) vs. 78mmHg (37-182), p=0.03; maximum intra-rectal pressure 60mmHg (90-110) vs. 76mmHg (31-178); p=0.01; defecation index 1.1 (0.1-23.0) vs. 3.2 (0.5-29.0); p=0.001). Dyssynergia on ARM and BET got corrected in 22/34 (65%) and 18/30 (60%) patients. At a 1-month follow up, 23/37 (62%) patients reported satisfactory symptomatic improvement. Biofeedback not only improves symptoms but also anorectal physiological parameters in patients with FED.

High-resolution Anorectal Manometry Findings in Dyssynergic Defecation

Introduction: Dyssynergic defecation (DD) is the most common disorder of defecation and affects up to 40% of patients with chronic constipation. Four types of DD have been defined by anorectal manometry, these are characterized by a paradoxical increase in anal pressure with (type I) or without (type II) adequate increase in rectal pressure and failure of reduction in anal pressure with (type III) or without (type IV) adequate increase in rectal pressure. It is unknown whether there are any differences between manometric parameters in DD types and the frequency of DD in our population. Methods: Study of patients who underwent high-resolution anorectal manometry for functional constipation during January 2013 to July 2015 in a tertiary referral center. For statistical analysis, the frequencies were expressed as percentages and comparative statistics by Student's T-Test and Wilcoxon rank test were applied, and relationships between manometric findings were evaluated by calculation of Spearman's correlation coefficient. P values < 0.05 were considered significant. Results: DD was found in 58 subjects, of which 81% (N = 47) were women. The average age was 42.95 ± 19.52. In the population with DD there was a positive correlation between the intrarectal pressure (IRP) and the anal canal length (r = 0.405 p = 0.002), the first sensation and height (r = 0.406, p = 0.002), the anorectal differential pressure (ARDP) and the anal relaxation percentage (r = 0.560, p < 0.001), the IRP and maximum sphincter pressure at rest MaxSPR (r = 0.480, p < 0.001), and in the IRP and the ARDP (r = 0.567, p < 0.001). The most common type of DD was the type I in 58.6% (N = 34), followed by type III in 19% (N = 11), Type II in 17.2% (N = 10) and Type IV in 5.2% (N = 3). Significant differences in the anal residual pressure between the group I and IV DD (103.25±46 vs 45.40±34 mmHg p < 0.05, see FIGURE1) were found. We found differences in the first sensation between DD subtypes according to gender (p < 0.05, see FIGURE2).Figure 1Figure 2Conclusion: DD is more common in women and type I is the most common in our population. The anal residual pressure distinguishes between the type I and the type IV. There are gender variations in rectal sensitivity among the dyssynergic defecation subtypes. We assume that these differences may be related to visceral hypersensitivity. The categorization of the types of DD perhaps will allow us to provide prognostic information and guide the direction of treatment.

Comparison of High-Resolution Anorectal Manometry Parameters in Constipation vs Fecal Incontinence with Significant Rectal Descent by Dynamic Pelvic Magnetic Resonance Imaging

Introduction: Clinically undetected internal rectal prolapse or significant rectal descent can be demonstrated via MRI defecography (D-MRI). It is unknown if rectal prolapse is diagnosed more frequently using D-MRI in patients with fecal incontinence (FI) compared to patients with constipation (C). The purpose of our study is to retrospectively compare the diagnostic rate of rectal prolapse in patients with constipation with that for the patients with fecal incontinence, and compare the HR-ARM findings between the two patient populations. Methods: This is a retrospective study of rectal prolapse found in patients with fecal incontinence and constipation who underwent HR-ARM and DP-MRI. Statistical analysis was performed using one-tailed Student's t test with unequal variances. Results: The rate of rectal prolapse or significant rectal descent (>3 cm) found in FI patients was 86% 12/14, versus 31% 12/39 in C patients and 50% 2/4 in patients with both FI/C. FI patients with significant rectal descent had decreased mean (57.8 vs 84, p < 0.01) and maximum (61.7 vs 92, p < 0.01) resting sphincter pressure, decreased maximum squeeze sphincter pressure (98.75 vs 219.8, p < 0.01), decreased length of functional anal canal (hpz) (2.7 vs. 3.4, p=0.01), decreased residual anal pressure (46 vs. 75.6, p < 0.01) and decreased intrarectal pressure at rest (39.4 vs 73.3, p=0.01) compared to patients with C and similar MRI findings. Conclusion: A higher proportion of patients with fecal incontinence as a presenting symptom are found to have rectal prolapse on DP-MRI than patients with constipation. A pattern of decreased resting sphincter pressure, squeeze sphincter pressure, length of functional anal canal, residual anal pressure and intrarectal pressure may be more characteristic for patients with FI and DP-MRI findings of rectal descent.Table 1: HR-ARM Comparison of Patients with Constipation versus Fecal Incontinence with Significant DP-MRI Rectal Descent

Structural Defects Found on Magnetic Resonance Defecography May Correlate with Increased Intrarectal Resting Pressure on High Resolution Anorectal Manometry in Patients with Constipation

Introduction: High resolution anorectal manometry (HR-ARM) and magnetic resonance defecography (MR defecography) are both modalities of assessing for anorectal dysfunction. HR-ARM assesses multiple manometric parameters while MR defecography evaluates pelvic organ structure and functional information regarding evacuation. Patients with constipation undergoing evaluation for defecatory dysfunction may undergo one or both of these testing modalities. To date, there is little data comparing HR-ARM to MR defecography. The aim of this study is to determine whether structural abnormalities on MR defecography correlate with findings on HR-ARM in patients with constipation. Methods: This is a single-center retrospective study comparing results between HR-ARM and MR defecography in patients with constipation who underwent both testing modalities. MR defecography was first used to evaluate for presence of significant structural defects including rectocele >3cm, cystocele >3cm, or pelvic floor descent >3cm below pubococcygeal line during strain. Multiple manometric findings from HR-ARM were then compared between patients with and without structural defects using Student's t-test. Results: Forty-six patients with constipation (age 19-74) undergoing HR-ARM also underwent MR defecography. All except for one patient were female; 82% Caucasian, 8.7% African American, and 8.7% Hispanic. Twelve had significant structural findings: rectocele >3cm (n = 2), cystocele >3cm (n = 1), and abnormal pelvic floor descent (n = 9). Comparing HR-ARM in the 12 patients with structural defects to the 36 without defects, only two parameters were statistically different between the two groups. Interestingly, patients with structural defects had higher resting intrarectal pressure (73.3 mmHg vs 43.9 mmHg, p=0.02) when compared to those without defects. Those with structural defects also had higher squeeze sphincter pressures (219.8 mmHg vs 160.2 mmHg, p=0.03). Conclusion: In patients with constipation undergoing both HR-ARM and MR defecography, it was determined that structural abnormalities on MR defecography were associated with higher resting intrarectal pressures and squeeze sphincter pressures on HR-ARM. This may be helpful in providing a diagnostic prediction for structural defects in patients with constipation undergoing workup with HR-ARM.

High-resolution Anorectal Manometry in Parkinson Disease With Defecation Disorder: A Comparison With Functional Defecation Disorder.

To investigate the characteristics of high-resolution anorectal manometry (HR-ARM) in Parkinson disease (PD) patients with defecation disorder (DD) compared with patients with functional defecation disorder (FDD). DD is a common gastrointestinal symptom in PD. HR-ARM is a relatively new and reliable method for detecting DD. A cohort of PD patients with DD was matched with FDD patients. Defecatory symptoms were investigated by questionnaire. Anorectal motility and sensation were evaluated by HR-ARM. Differences in defecatory symptoms, sensorimotor parameters, and DD type were analyzed. Defecatory symptoms and manometric variables obtained in early-stage PD were compared with advanced stage, and relationships between manometric parameters and evacuatory symptoms explored. Straining and sensation of blockage was experienced significantly more in PD than FDD, and stool consistency more severely affected. Maximum squeeze and intrarectal pressure during defecation in PD was lower than in FDD. Anal resting and residual pressures, duration of sustained squeeze, threshold volumes for first sensation, urgency, and maximum discomfort were similar between groups. PD patients presented predominantly with inadequate propulsive forces, whereas FDD patients showed dyssynergic defecation. Defecatory symptoms and manometric parameters did not differ between stages of PD. PD patients with DD experienced more straining and sensation of blockage than FDD patients, possibly related to inadequate anorectal motility and paradoxical anal contraction of pelvic floor. Impaired squeeze response and inadequate propulsive forces are specific to anorectal function of PD patients with DD, compared with FDD, with abnormalities unchanged between early and advanced PD.

OC-084 Clinical significance of anorectal excitatory reflex (rectal contraction) in controls and patients with faecal incontinence

<h3>Introduction</h3> <h3>Aim </h3> To study the response of the rectum to the voluntary squeeze of anal sphincters in normal controls in comparison with patients with faecal incontinence. <h3>Method</h3> Lower rectal diameter and intrarectal pressures are recorded during rest and squeeze by lateral view evacuation proctography (defecography) and anorectal manometry in 35 normal controls and in 35 patients with faecal incontinence. <h3>Results</h3> 26 and 27 out of 35 patients in each group were males, with average age of 39 years old. There is highly significant difference in resting rectal pressure (RRP) and squeeze rectal pressure (SRP) and resting rectal diameter (RRD) and squeeze rectal diameter (SRD) in normal controls (p &lt; 0.01). There is also significant correlation between the change in rectal diameter and rectal pressure (p = 0.02). No significant different in RRD and SRD in group of patients complaining of faecal incontinence (p = 0.095), with no correlation between the change in rectal pressure and diameter (0.0727). There is no significant difference in RRP (p = 0.169). There is highly significant difference in SRP (p &lt; 0.01), change in rectal pressure (p &lt; 0.01) and change in rectal diameter (p &lt; 0.01). There was delay in the rectal pressure of average of 1.1 sec (0.5–1.4) between the squeeze and rectal pressure, suggestive of retrograde anorectal wave. <h3>Conclusion</h3> The rectal contraction during squeeze (rather than inhibitory, as suggested before) may allow retrograde evacuation of the rectum and delayed defecation in normal controls. This act is weak in incontinence group which may contribute to pathophysiology in those patients. <h3>Disclosure of interest</h3> None Declared.