Introduction

In 2019, an international anorectal physiology working group published a consensus paper (‘London’) with recommendations for the performance of anorectal manometry (ARM) and balloon expulsion testing (BET)¹. However, little is known on the implementation of these recommendations in the clinical setting.

Aims & Methods

We aimed to (1) evaluate, on a national level, current practice in all aspects of ARM and BET performance and interpretation, (2) identify gaps compared to both updated international recommendations and between testing centers, and if present, (3) jointly draft a national position paper, advocate for its instillation, and examine the impact of the publication on the identified gaps.
Between October and November 2020, gastroenterologists from 20/20 (100%) centres who perform and/or interpret ARM in Israel completed a 61- item online survey encompassing all stages of ARM and BET testing (preparation, testing protocol and reporting).

Results

Major inconsistencies between centres were demonstrated (table 1, baseline survey), especially in reporting, including (1) the use of London classification for description of anorectal dysfunction (2) lack of normal values for reference (3) selective reporting of anal squeeze pressure and anal slow waves, and (4) report template and language. High concordance (>90%) between centres in most stages of preparation and testing was noted, consistent with international recommendations, with the exception of testing for anal squeeze endurance, cough, rectoanal inhibitory reflex (RAIR) and BET methodology.

Table 1. Changes in performing anorectal manometry and balloon expulsion testing following local position paper publication and hands-on educational course.

	Baseline survey N=20	Follow up survey N=22	P value for difference
Squeeze endurance testing- n (%)	17 (85%)	20 (91%)	NS
Cough/ Valsalva testing - n (%)	15 (75%)	20 (91%)	NS
RAIR 50 ml, repeat to 100 ml if needed - n (%)	5 (25%)	10 (45%)	NS
BET - on toilet and dedicated expulsion balloon - n (%)	2 (10%)	6 (27%)	NS
BET Balloon fill: water - n (%)	5 (25%)	10 (45%)	NS
Volume of BET balloon: 50 ml - n (%)	15 (75%)	22 (100%)	NS
London classification on report - n (%)	13 (65%)	22 (100%)	<0.01
Anal squeeze pressure on report: absolute and increment - n (%)	6 (30%)	13 (59%)	0.07
Anal slow waves on report- n (%)	4 (21%)	4 (18%)	NS

Following these results, an ARM and BET position paperwas endorsed by the Israeli Neurogastroenterology Society (October 2021), followed by a free-of-charge hands-on educational course focused on proper performance of tests (Feb 2022) and publication of the final version of the position paper (Jan 2023)². One year following publication, in a repeat survey of centres (22/24; 4 new centres), almost all responders (19/22;86%) stated they have changed their clinical practice following publication of the national position paper, and 21/22 (95%) reported now using the published normal values. Compared to the baseline survey, the following improved (table 1, follow up survey): (1) reporting according to the London classification, and (2) uniform volume of balloon used for BET. High concordance (>90%) was also demonstrated now for performing squeeze endurance and cough, as well as reporting templates, but not for RAIR or for the use of a dedicated evacuation balloon or sitting position for BET.

Conclusion

The current study highlights major gaps in ARM and BET testing between consensus papers and clinical practice on a national level. Publication of a national position paper along with an educational curriculum can address existing gaps.

References

¹Carrington et al. NGM, 2019
²https://ima-contentfiles.s3.amazonaws.com/Ne201_AnorectalManometry.pdf

Disclosure

None

Introduction

Defecatory dysfunction (DD) is a common cause of chronic constipation resulting from functional abnormalities or structural pelvic pathologies. Accurate diagnosis requires combining anorectal manometry (ARM), balloon expulsion test (BET), and defecography. This study evaluates the diagnostic utility of these modalities and explores uncertainties in their performance and interpretation.

Aims & Methods

This retrospective study included 325 adult patients assessed for DD between 2020 and 2023. All patients went through ARM, BET in the left lateral position, and defecography. Statistical associations between test outcomes were analyzed to assess diagnostic concordance and significance.

Results

A strong correlation was observed between ARM and defecography, with 65% of patients with normal anal relaxation on ARM achieving normal rectal evacuation on defecography (p < 0.0001). Conversely, patients with paradoxical contraction during ARM demonstrated a higher likelihood of evacuation failure. BET demonstrated high specificity but limited sensitivity in association with relaxation on ARM and evacuation on defecography. BET failure did not demonstrate a significant association with the presence of pelvic floor pathologies.

Conclusion

Combining ARM, BET, and defecography provides a comprehensive framework for diagnosing DD, addressing its functional and structural components. This integrated approach facilitates targeted interventions, ultimately improving clinical outcomes.

References

Chronic constipation is a common disorder with multifactorial pathophysiology, including pelvic floor dysfunction (Bharucha & Lacy, 2020). Symptomatic pelvic floor disorders affect a significant proportion of women (Nygaard et al., 2008). High-resolution anorectal manometry (HRAM) and rectal balloon expulsion tests are critical for diagnosing defecatory disorders (Prichard et al., 2017; Bharucha & Coss-Adame, 2022). Standardized protocols, including the London Classification, have improved the diagnostic accuracy of anorectal functional tests (Carrington et al., 2020; Carrington et al., 2018). Imaging modalities such as magnetic resonance defecography complement functional testing (Reiner et al., 2011; Carter et al., 2020). Variations in body position influence anorectal test results (Su et al., 2019; Wu et al., 2017; Tsunoda et al., 2022; Ratuapli et al., 2013). Comparative studies emphasize the complementary role of manometry, balloon expulsion, and defecography (Blackett et al., 2022; Heinrich et al., 2015). Recent advances suggest HRAM improves detection of specific defecatory mechanisms (Deb et al., 2022; Sharma et al., 2020), supported by international consensus guidelines (Wald et al., 2021; Rao & Tetangco, 2020; Lee & Bharucha, 2016).

Disclosure

no conflict of interest

Introduction

Anorectal manometry (ARM) is required to diagnose functional defecation disorders (FDD) in constipated patients. The International Anorectal Physiology Working Group introduced into clinical practice a standardized sequence of manoeuvres to perform ARM (London Protocol) (1). The London protocol suggests performing three push attempts, each of 15s duration, to assess recto-anal coordination and therefore to diagnose FDD, with a consensus <75% between experts. However, some papers consider a 5s push sufficient to detect FDD (2,3).

Aims & Methods

Therefore, the aim of this study was to assess the diagnostic accurac of a simplified ARM protocols featuring three pushes attempts (each of 5s) in comparison with IAPWG recommendations.
High-Definition ARM (HD-ARM) traces from 105 constipated patients (82 F, mean aged 53.5 ± 16.7 years) who had performed HD-ARM for clinical practice were retrospectively reviewed. HD-ARM were performed according to the IAPWG Protocol. All patients underwent the balloon expulsion test at the end of HD-ARM as suggested by IAPWG protocol. HD-ARM traces were re-evaluated considering the first five seconds of each push (as if each push featured only five seconds).
New diagnosis was made based on this modified protocol and compared with the one made according to London Protocol, to evaluate whether these modifications could affect the final diagnosis.

Results

According to the London Protocol, the qualitative best pushes were the first, the second or the third in 35.2%, 28.6% and 36.2% of patients, respectively. Eighty-seven patients (82.9%) failed the balloon expulsion test.
Mean rectal pressure did not differ between the modified protocol and the London protocol (37.1 ± 23 vs 34.3 ± 23.2, p=0.38). However, we observed a significant increase in the mean anal pressure with the modified version of the protocol compared to the London protocol (75.6 ± 33.1 vs 90.8 ± 37.3, p<0.002).
Regarding the diagnostic accuracy, we observed a moderate concordance between the modified protocol and the London protocol k=0.77, Table 1). In details, if we had used this modified version of protocol, 18 patients (17.1%) would have changed their final diagnosis (Table 1).

Table 1. Cohen's K diagnosis concordance according to London Protocol (k=0.773)

Conclusion

Based on our results, a simplified ARM protocol using three 5s pushes shows moderate diagnostic agreement with the standard London protocol. While rectal pressures remained similar, anal pressures increased significantly, and 17.1% of patients received a different diagnosis. Therefore, the simplified protocol could reduce the diagnostic accuracy for FDD.

References

1. Carrington EV et al. Neurogastroenterol Motil. 2020 Jan;32(1):e13679.
2. Grossi U, et al. Gut. 2016 Mar;65(3):447-55.
3. Carrington EV, et al. Neurogastroenterol Motil. 2014 May;26(5):625-35.

Introduction

Constipation is a common anorectal symptom that causes significant changes in the patients' quality of life. Anorectal manometry (ARM) and magnetic resonance (MR) defecography are important tools in diagnosing disorders associated with constipation, which are mainly structural and/or functional. Pelvic floor dyssynergia is diagnosed in the presence of alterations in 2 of the following: defecation kinetics in ARM, balloon expulsion test (BET) and/or MR defecography.

Aims & Methods

Compare the findings in ARM and MR defecography, in patients with constipation.
Retrospective cohort study including patients who fulfilled the Roma IV criteria for functional constipation, who were submitted to ARM and MR defecography. The London classification was used to describe the findings in ARM, establishing 3 groups of patients: Group 1 with those who had normal anorectal coordination and normal BET, Group 2 had altered anorectal coordination and altered BET, and Group 3 with those who had inconclusive findings: altered anorectal coordination and normal BET or normal anorectal coordination with abnormal BET. The structural alterations considered significant in MR defecography were those described as moderate to severe, which lead to defecation obstruction.

Results

A total of 51 patients were included, most were female (98.0%), with a mean age of 55 ± 12 years. Regarding the ARM findings, 16 patients were in Group 1 (31.4%), 11 in Group 2 (21.6%) and 24 in Group 3 (47.1%). Forty-three patients had alterations in MR defecography (84.3%), with 42 patients having at least one structural alteration and the most common being rectocele (72.5%) and descending perineum syndrome (66.7%). Pelvic floor dyssynergia was diagnosed by MR defecography in 9 patients (17.6%).
In the group of patients with normal anorectal coordination in ARM and normal BET (Group 1: n=16), 14 had significant structural alterations in MR defecography (87.5%) and 2 patients had no alterations (12.5%). In the group of patients with altered anorectal coordination in ARM and altered BET (Group 2: n=11), 8 also had structural alterations in MR defecography (72.7%). In the group of patients with inconclusive findings in ARM (Group 3: n= 24), 20 had structural alterations (83.3%) and 3 patients had pelvic floor dyssynergia diagnosed by MR defecography (12.5%), 2 of whom had both alterations (8.3%). In this group, 3 patients had no alterations in MR defecography (12.5%).
Patients with pelvic floor dyssynergia, with or without structural alterations, had a significantly lower rectoanal pressure differential than those with solely structural alterations (-25.0 ± 27.1 vs 5.7 ± 30.0 mmHg, p=0.004). There were no statistically significant differences in the values of anal pressure at rest and voluntary contraction pressure between patients with pelvic floor dyssynergia and those with solely structural alterations (p=0.350 and p=0.833), as well as in the values of residual anal pressure, intrarectal pressure and percentage of relaxation during defecation (p=0.267, p=0.257 and p=0.348).

Conclusion

Most patients had alterations in MR defecography, regardless of the ARM findings. Therefore, it is important to interpret the results of the ARM in conjunction with an imaging test capable of identifying structural alterations that may condition defecation in patients with functional constipation. In addition, those with pelvic floor dyssynergia, with or without associated structural alterations, had a lower rectoanal pressure differential than those with solely structural alterations.

Introduction

Anorectal manometry (ARM) is one of the required investigations to diagnose defecation disorders according to Rome IV criteria. The International Anorectal Physiology Working Group (IAPWG) introduced into clinical practice a standardized sequence of manoeuvres to perform ARM (London Protocol) (Carrington EV, 2020). IAPWG Protocol suggested the need of performing three push attempts, each of 15s duration, to assess recto-anal coordination, with a consensus <75% between experts.

Aims & Methods

The aim of this study was to assess the diagnostic accuracy, compared to IAPWG recommendations, of simplified ARM protocols featuring:

• only two push attempts (each of 15 seconds);
• three pushes attempts (each of 10s);
• two pushes attempts (each of 10s)

High-Definition ARM (HD-ARM) traces from 150 patients (118 F, mean aged 54 years) who underwent ARM for faecal incontinence (n=37) or constipation (n=105) were retrospectively reviewed. All traces were performed according to the IAPWG Protocol. Firstly, we evaluated if the mean rectal and anal pressures were different among the three pushes. Subsequently, ARM traces were re-evaluated considering the following modifications to the IAPWG protocol:

• considering only the first two pushes (as if the third had never been performed);
• considering the first ten seconds of each push (as if each push featured only ten seconds);
• considering the first ten seconds of the first two pushes (as if the third had never been performed and the first two featured only ten seconds).

In all three cases, the best push (defined as the most qualitatively normal) among the available pushes was chosen.
New diagnoses were made based on these modified protocols and compared with the standard to evaluate whether these modifications could affect the final diagnosis.

Results

According to the IAPWG London Protocol, the qualitative best pushes were the first, the second or the third in 58, 45 and 47 patients, respectively. No statistically significative differences were found in anal and rectal pressures among the three pushes.
No statistically significative differences were found in anal and rectal pressures comparing the three modified protocols with the IAPWG’s one.
Regarding the diagnostic accuracy, all the proposed modified London Protocol showed an almost perfect concordance compared with the standard of practice (K=0.97, Tab.1). This result was confirmed for the constipated and incontinent patients’ subgroup.

Table 1 - Cohen's K concordance according to London Protocol among all patients and in constipated patients

		No disorders of rectoanal co-ordination	Normal expulsion with abnormal manometric pattern of rectoanal co-cordination	Abnormal expulsion with normal manometric pattern of rectoanal co-ordination	Abnormal expulsion with poor propulsion	Absormal expulsion with dyssynergia	Abnormal expulsion with poor propulsion and dyssynergia	Comparison of proportions (Kappa Cohen agreement)
All patients N=150	3 Push 15 sec	5	18	16	25	44	42	-
	2 Push 15 sec	5	18	14	25	45	43	k=0.974
	3 Push 10 sec	5	18	15	25	45	42	k=0.974
	2 Push 10 sec	4	19	15	25	45	42	k=0.966
Constpated patients N=105	3 Push 15 sec	3	15	10	14	30	33	-
	2 Push 15 sec	3	15	9	14	30	34	k=0.975
	3 Push 10 sec	3	15	9	14	30	34	k=0.975
	2 Push 10 sec	3	15	9	14	30	34	k=0.975

Conclusion

Based on our results, it seems that two pushes of ten second each may be enough to reach an accurate manometric diagnosis of defecation disorders. Performing only 2 push manoeuvres of 10s each may reduce the examination length of 55s, reducing patient’s discomfort and, likely, improving HD-ARM’s acceptability.

Introduction

High-resolution anorectal manometry (HRAM) is the most commonly used technique for studying functional anorectal disorders, including chronic constipation. However, alterations in the defecatory maneuver are inconclusive for diagnosing defecatory dysfunction, necessitating additional confirmatory testing. The study of the geometry and distensibility of the anal canal may be useful in evaluating patients with chronic constipation.

Aims & Methods

To evaluate the manometric characteristics and anal canal distensibility in patients with chronic constipation compared to a control group of healthy volunteers (HV). The study included 15 healthy controls and 11 patients with chronic constipation. All participants underwent HRAM (Medtronic®), EndoFLIP (Medtronic®), and the balloon expulsion test (BET; Matla Systems®). HRAM was performed according to the London protocol. Distensibility index (DI) values were calculated at rest, during voluntary contraction (VC), and during the defecatory maneuver (DM) with volumes of 30, 40, and 50 mL.

Results

The mean age was 32.4 ± 12.8 in HV and 45.2 ± 12.4 in patients with CC (p = 0.012). Most patients with CC were women, 10 (90.9%). Among CC patients, 9.1% had stool consistency classified as Bristol 3-4 compared to 95% of HV (p < 0.001). The defecatory pattern was < 3 weekly bowel movements in 54.5% of CC patients. Obstructive defecation perception predominated in 7 patients (66.7%), while 1 (9%) had slow transit, and 3 (27.3%) had obstructive defecation and fecal incontinence (multiple sclerosis). All HV had normal BET, with a mean balloon expulsion time of 13.3 ± 10.4 seconds.
The HRAM findings revealed that the percentage of anal relaxation was 31.2 ± 18 in HV and 7 ± 23 in CC patients (p < 0.001). The rectoanal gradient (RAG) measured -28.3 ± 25 in HV and -51.5 ± 36.8 in CC patients (p = 0.06). Significant differences in rectal sensitivity were observed between CC patients and HV. The first sensation threshold was 50.5 ± 25.2 mL in HV compared to 87.3 ± 47.9 mL in CC patients (p = 0.018). Similarly, the urge threshold was 126.8 ± 35.4 mL in HV versus 177.5 ± 44 mL in CC patients (p = 0.004). The maximum tolerated volume also differed, recorded as 157.5 ± 37.9 mL in HV and 224.3 ± 60.3 mL in CC patients (p = 0.008).

EndoFlip results are presented in Table 1. The DI demonstrated better diagnostic performance than HRAM defecatory parameters for predicting balloon expulsion: DI-30 mL: 0.850; 95% CI: 0.701–0.999 (p=0.011); DI-40 mL: 0.817; 95% CI: 0.602–1 (p=0.021); DI-50 mL: 0.775; 95% CI: 0.525–1 (p=0.045); % anal relaxation: 0.742; 95% CI: 0.504–0.980 (p=0.078); RAG: 0.767; 95% CI: 0.540–0.993 (p=0.051).

Table 1. EndoFlip results
DI	Maneuver	Healthy controls	CC-normal BET	CC-abnormal BET	p-value
30 mL	Rest Squeeze Push	0.6 (0.4-0.7) 0.3 (0.2-0.4) 0.9 (0.6-1.3)	0.5 (0.4-1.9) 0.3 (0.2-0.5) 1.4 (0.4-1.8)	0.6 (0.4-0.7) 0.3 (0.2-0.4) 0.4 (0.3-0.5)	NS NS 0.036
40 mL	Rest Squeeze Push	0.4 (0.3-0.6) 0.3 (0.2-0.4) 1.2 (1.1-3)	0.9 (0.6-3.5) 0.2 (0.2-1) 2.2 (0.9-2.9)	0.7 (0.3-2) 0.5 (0.2-0.7) 0.5 (0.2-1.1)	0.05 NS 0.05
50 mL	Rest Squeeze Push	0.8 (0.5-1) 0.3 (0.2-0.7) 3.1 (1.6-4.7)	2.2 (1.4-3.6) 0.6 (0.4-1.8) 4.2 (2.7-5.7)	1.7 (0.7-3.4) 0.9 (0.2-1.5) 1.2 (0.4-2.7)	0.008 NS 0.08

Conclusion

Patients with chronic constipation exhibit significant differences in HRAM defecatory parameters and rectal sensitivity compared to control subjects. Although the sample size of patients with constipation is small, the DI demonstrates superior diagnostic performance compared to HRAM defecatory parameters about the BET.

References

None

Disclosure

Nothing

Introduction

Anorectal manometry (ARM) is the most widely established diagnostic tool for studying defecation disorders. The London protocol and classification provide a standardized format for performing and interpreting High Resolution ARM. However, these are not based on clinical evidence, but only on expert consensus.

Aims & Methods

The aims of our study were to assess the impact of protocol modification on diagnostic agreement, focusing on resting pressure and push using the High Definition-ARM (HD-ARM) probe. A retrospective analysis was conducted of HD-ARM recordings performed in patients with chronic constipation at our digestive pathophysiology laboratory from January to October 2022. Evaluation of recordings was performed by applying both the London protocol and the proposed changes, as reported below. Resting pressure was assessed by combining modifications in both the baseline rest period (60, 50, 40, 30, 20 and 10 s) and stabilization period (3, 2 and 1 min). Each of the pushes was evaluated for 10 s, selecting the most qualitatively normal one for analysis. The diagnostic agreement between the standard protocol and the proposed modifications was compared by using Cohen's Kappa (k).

Results

	Mean anal pressure, (SD) mmHg	Mean rectal pressure, (SD) mmHg	Abnormal expulsion with dyssynergia, n	Abnormal expulsion with poor propulsion, n	Abnormal expulsion with poor propulsion and dyssynergia, n	Abnormal expulsion with normal manometric pattern of rectoanal coordination, n	Normal expulsion with abnormal manometric pattern of rectoanal coordination, n	No disorder of rectoanal coordination, n	Cohen's Kappa
Push 15 s	79.7 (40.5)	43.3 (26.6)	24	8	15	5	13	4	/
Push 10 s	82.7 (43.0)	44.2 (27.4)	24	8	15	5	13	4	1.000

Recordings of 69 patients with chronic constipation (53 F, mean age 53 [SD: ± 17]) were analyzed. At resting pressure assessment, performed according to the London protocol and classification, 30% and 27% of patients presented with anal hypotonia and hypertonia, respectively. As recording periods gradually changed, there was a concomitant change in some diagnoses; up to a stabilization period of 2 min and a baseline rest period of 30 s, a strong agreement with the standard protocol was maintained (κ = 0.823). Correlation was perfect between pushes assessed at 15 and 10 s (k = 1.000), respectively.

Conclusion

A 2-min stabilization period, 30-s baseline rest period, and 10-s push analysis allow a reduction of 105 s in study duration, thus obtaining very good diagnostic accuracy compared to the London protocol. In conclusion, we provide the first evidence-based study of a modified HD-ARM probe protocol (focusing on resting pressure and push) by analyzing recordings of patients with chronic constipation.