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

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

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.

Introduction

Dynamic transperineal ultrasound (DTP-US) enables the calculation of the pubo-rectal muscle (PR) length and the ano-rectal angle (ARA) width, offering a static and dynamic evaluation of the pelvic floor. DTP-US is usually followed by a Gel Expulsion Test (GET), in the same way that high-resolution anorectal manometry (HR-AM) is usually followed by balloon expulsion test (BET).
DTP-US+GET may be an innovative way of testing constipated patients for functional defecation disorders (FDD) diagnosis.

Aims & Methods

Our aims were: to determine normal values for DTP-US; to explore accuracy of DTP-US+GET in diagnosing a Rome IV FDD. To obtain normal values, 17 healthy females (HVs) underwent DTP-US+GET.
Fifty-six females meeting Rome IV criteria for functional constipation (FC) underwent DTP-US+GET.
Measurements were acquired in supine (SUP) and left lateral (LL) positions. At rest, during squeezing and during straining were evaluated: PR length; ARA width; variation in length of PR and in width of ARA between rest and squeezing or straining (expressed as a percentage of the resting measurement).
All 56 FC patients previously underwent HR-AM+BET. DTP-US examiners were blinded to HR-AM+BET result.
GET was performed in a sitting position filling the rectum with ultrasound gel (120 ml). GET was considered positive if patient was unable to evacuate gel after 30 seconds.

Results

No differences were observed in mean age between HVs and FC groups (p=0.57).
Thirty-eight patients (67.86%) showed a FDD on HR-ARM+BET. Thirty-eight patients showed a positive GET. No HVs failed GET.
DTP-US straining results are summarized in Table-1. FDD patients showed different mean values for straining measurements compared with HVs (p<0.001): HVs showed an increase in PR length and an increase in ARA; FDD showed a length reduction in PR and a closure of ARA.
To diagnose FDD, at least 3 out of 4 abnormal values on percentage variations during straining and a positive GET were needed: abnormal DTP-US+GET showed a strong association with FDD (OR 198.33), with a sensibility of 92.11%, a specificity of 94.44% and an accuracy of 94.42% in diagnosing FDD.

Table-1 –DTP-US values and differences between HV and FDD group

	HV group (Mean [95% CI])	FDD group (Mean [95% CI])	p-value
PR Lenght Straining SUP	67.39 [63.19 - 71.59]	58.07 [54.08 - 62.06]	<0.01
ARA Straining SUP	117.24 [109.18 - 125.3]	97.19 [89.35 - 105.04]	<0.01
PR Lenght Straining DLS	71.08 [66.41 - 75.75]	59.24 [55.35 - 63.13]	<0.01
ARA Straining DLS	113.23 [106.81 - 119.47]	85.8 [79.47 - 92.12]	<0.01
Δ PR Lenght Straining SUP	9.33 [5.77 - 12.83]	-1.21 [-5.42 - 3.01]	<0.01
Δ ARA Straining SUP	15.88 [8.64 - 23.12]	-7.42 [-13.09 - -1.75]	<0.01
Δ PR Lenght Straining DLS	14.91 [8.23 - 21.5]	-2.15 [-6.25 - 1.95]	<0.01
Δ ARA Straining DLS	20.34 [10.63 - 30.05]	-3.89 [-9.0 - 2.11]	<0.01

Conclusion

DTP-US+GET is an innovative and promising new technique to diagnose FDD in constipated patients. It can be performed by a skilled gastroenterologist, is not expensive and requires only a convex probe, with no radiation exposure. In this pilot study, we provided normal values for DTP-US and tested these values to diagnose FDD in a set of constipated patients, obtaining a diagnostic accuracy of 94.42%.

Introduction

Functional Defecation Disorders (FDD) are a frequent cause of refractory chronic constipation (CC). FDD diagnosis requires focused anorectal physiology testing, which is not easily available outside referral centers. Therefore, easy-to-perform tools to select patients needing anorectal physiology testing would be very welcome.

Aims & Methods

Our aim was to evaluate accuracy and Odds Ratio (OR) of a straining questionnaire (SQ) and a digital rectal examination augmented by abdomen palpation on straining (augmented-DRE) on predicting a FDD in refractory CC patients.
Two-hundred and thirty-eight CC patients failing a 4-week conservative treatment were enrolled. A SQ (Which muscles do you mainly use when you push to defecate?) was administered to all patients before entering the study (T0) and after a 30-day fiber/laxative trial (T30). The possible answers were: “belly muscles”; “anal muscles”; “both”; “Don’t know/No answer”.
Augmented-DRE and BET were performed at T0 and at T30.
At T30, all patients underwent anorectal manometry.
OR and accuracy were calculated for SQ, augmented-DRE and combinations in predicting and diagnosing both dyssynergic defecation (DD) and inadequate defecatory propulsion (IDP).
Sixty-one healthy volunteers (HVs) underwent SQ and BET.

Results

One-hundred and twenty patients showed features of Rome III FDD: 82 DD and 38 IDP.
“Anal Muscles” response was associated to both DD and IDP, with an OR of 13.6 and 5.85 (p<0.001) and an accuracy of 78.5% and 66.4%, respectively.
“Failed anal relaxation” on augmented-DRE was associated with a DD, with an OR of 21.4 and an accuracy of 73.1%. “Failed abdominal contraction” on augmented-DRE was associated with an IDP with an OR>100 and an accuracy of 97.1%.
SQ and augmented-DRE were reproducible between T0 and T30 (k=0.97 and k=0.517, respectively).
Regarding combinations of SQ and augmented-DRE, the combination increased the accuracy of the diagnostic tool for DD compared to SQ or augmented-DRE alone (Table-1).
All HVs had a negative BET and one answered SQ with “Anal strain”.

Table-1 – Accuracy and diagnostic test evaluator of SQ and augmented-DRE in predicting and diagnosing FDD

Conclusion

Our data support screening CC patients for DD and IDP, at all levels of care, by SQ and augmented-DRE, to improve the management and appropriateness of the referral to anorectal physiology testing.

Introduction

Functional Defecation Disorders (FDD) are a frequent cause of refractory functional constipation (FC). The diagnosis of FDD requires anorectal manometry (ARM) and a balloon expulsion test (BET), which are not easily available outside referral centers. FDD often do not respond to conventional treatments, while they respond to biofeedback.

Aims & Methods

The aim of our study was to evaluate if pain reported by patients during defecation or elicited during digital rectal examination (DRE) predicted a FDD diagnosis in a cohort of refractory FC patients.

Two-hundred and thirty-eight FC (Rome III Criteria) patients failing a 30-day conservative treatment trial (increased fiber and fluids, tailored laxatives) were enrolled in the study. The presence of weekly anorectal pain during defecation and the elicited pain/tenderness consequent to a stretching of the levator ani muscle during DRE (DRE-pain) had been evaluated before and after the macrogol trial. Possible causes of organic anorectal pain were excluded.
All patients underwent:

• ARM+BET;
• barium defecography, if ARM and BET were discordant;
• second DRE with evaluation of DRE-pain.

OR and accuracy were calculated for both pain during defecation and DRE-pain in predicting a Rome III FDD.

Results

One hundred and twenty patients (50.42%) showed features of FDD: 82 dyssynergic defecation (DD) and thirty-eight inadequate defecatory propulsion (IDP). Thirty-three structural outlet obstructions (SOO) were identified using barium defecography.
Pain during defecation was strongly associated with DD, with an OR of 7.85 (p<0.001) and an accuracy of 75.2% in diagnosing a FDD (Tab.1).
DRE-pain was strongly associated with DD, with an OR of 11.78 (p<0.001) and an accuracy of 77.3% in diagnosing DD (Tab.1). Furthermore, DRE-pain showed a very good reproducibility between T0 and T30 (Cohen’s K=0.87).
The combination of pain during defecation and DRE-pain showed an even stronger association to DD compared to single items, with an OR of 20.84 and an accuracy of 82.8% in diagnosing DD (p<0.001, Tab.1).
Neither pain during defecation nor DRE-pain were predictive of IDP.

Table 1 - Association and diagnostic devaluation of reported pain during defecation and DRE-pain

Abbreviations: DD=dyssynergic defecation; OR=odds ratio; 95% CI=95% confidence interval; Sens.=sensitivity; Spec.=specificity; PPV=positive predictive value; NPV=negative predictive value; Acc.=accuracy; DRE-pain= pain/tenderness consequent to a traction on the levator ani muscles during digital rectal examination

Conclusion

Anorectal pain during defecation or elicited during DRE were shown to be predictive of a DD diagnosis in FC patients. An early referral to anorectal physiology testing may be considered in patients presenting these clinical features, leading to an improvement in their management.