Evaluation of the Fast Fill Technique for Anal Acoustic Reflectometry (AAR) in the Incontinent Anal Sphincter

Anal Acoustic Reflectometry (AAR) is a technique that has been studied in our department over the last 6 years. Sound waves pass into a balloon placed in the anal canal and are used to measure the cross-sectional area. By gradually increasing and decreasing the pressure in the balloon the investigators can measure the pressure at which the cross-sectional area starts to increase and decrease, and the anal canal starts to open and close. This assessment mimics the natural opening and closing of the anal canal and the effect of squeezing the muscles.

The gold standard investigation of the anal sphincter muscles has been manometry which measures anal canal pressure at rest and during squeeze. However, it has limitations. Despite the two measurements being within the normal range, some patients can have significant faecal incontinence. This has prompted clinicians to search for a better investigation to guide the management of this condition.

AAR is a reproducible and repeatable technique that has been used as a research technique in the assessment of faecal incontinence. It has been shown to correlate with symptom severity and, unlike manometry, is able to distinguish between different symptomatic subgroups with faceal incontinence. In our studies so far the investigators have increased the bag inflation pressure a step at a time which means that each study takes about 20 minutes to perform. The limitation of this method is that during the measurement of squeeze pressure the sphincter muscle is subject to fatigue. A recent study using the acoustic technique in the urethra has demonstrated a faster method of recording measurements over an 8 minute period. The investigators propose to study the fatiguability effects of this faster technique and validate the method against the existing step-wise technique and standard anal manometry.

Patients will be randomised into two groups:

1. Stepwise then fast-fill
2. Fast-fill then stepwise

Study Overview

• Status: Completed
• Conditions: Faecal Incontinence

• Study Type: Observational
• Enrollment (Actual): 36

Contacts and Locations

Study Locations

• United Kingdom
  • Greater Manchester
    • Manchester, Greater Manchester, United Kingdom, M23 9LT
      • University Hospital of South Manchester

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

Patients presenting to the pelvic floor clinic and neurogastroenterology with symptoms of faecal incontinence

Description

Inclusion Criteria:

• adults over 18 years
• have capacity to consent to the study
• patients with symptoms of faecal incontinence

Exclusion Criteria:

• minors under age of 18 years old
• patients who lack capacity to consent

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort
Faecal Incontinence: fast-fill measurement first; Observational study where patients with faecal incontinence undergo two AAR measurements; one with the original step-wise technique and the second with the newer fast-fill technique. A further standard manometry measurement will be taken. 18 patients will undergo fast-fill measurement first.
Faecal Incontinence: step-wise measurement first.; Observational study where patients with faecal incontinence undergo two AAR measurements; one with the original step-wise technique and the second with the newer fast-fill technique. A further standard manometry measurement will be taken. 18 patients will have step-wise measurement first.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Opening Pressure	Opening Pressure (Op - cm H2O) - the point at which the anal canal just begins to open	10 minutes
Opening Elastance	Opening Elastance (Oe - cm H2O/mm2) - the resistance of the anal canal to stretch	10 minutes
Closing Pressure	Closing Pressure (Cp - cm H2O) - the pressure at which the anal canal closes after a period of opening	10 minutes
Closing Elastance	Closing Elastance (Ce - cm H2O/mm2) - the ability of the anal canal to close passively after a period of stretch	10 minutes
Hysteresis	Hysteresis (%) - the energy dissipated during opeing and closing of the anal canal	10 minutes
Squeeze Opening Pressure	Squeeze opening pressure (SqOp - cm H20) - the pressure at which the anal canal just starts to open whilst the patient is voluntarily trying to keep the anal canal closed	10 minutes
Squeeze Opening Elastance	Squeeze opening elastance (Sq)e - cm H20/mm2) - the resistance of the anal canal to stretch whilst the patient is voluntarily trying to keep the anal canal closed	10 minutes

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Manometry - Resting Pressure	anal manometry measured in cmH20	10 minutes

Collaborators and Investigators

• Sponsor: Manchester University NHS Foundation Trust
• Investigators: Study Chair: Karen J Telford, MBChBMDFRCS, University Hospital of South Manchester

Publications and helpful links

General Publications

• Klarskov N, Saaby ML, Lose G. A faster urethral pressure reflectometry technique for evaluating the squeezing function. Scand J Urol. 2013 Dec;47(6):529-33. doi: 10.3109/21681805.2013.776629. Epub 2013 Mar 19.
• Hornung BR, Mitchell PJ, Carlson GL, Klarskov N, Lose G, Kiff ES. Comparative study of anal acoustic reflectometry and anal manometry in the assessment of faecal incontinence. Br J Surg. 2012 Dec;99(12):1718-24. doi: 10.1002/bjs.8943. Erratum In: Br J Surg. 2013 Jan;100(2):301.
• Mitchell PJ, Klarskov N, Telford KJ, Hosker GL, Lose G, Kiff ES. Viscoelastic assessment of anal canal function using acoustic reflectometry: a clinically useful technique. Dis Colon Rectum. 2012 Feb;55(2):211-7. doi: 10.1097/DCR.0b013e31823b2499.
• Mitchell PJ, Klarskov N, Telford KJ, Hosker GL, Lose G, Kiff ES. Anal acoustic reflectometry: a new reproducible technique providing physiological assessment of anal sphincter function. Dis Colon Rectum. 2011 Sep;54(9):1122-8. doi: 10.1097/DCR.0b013e318223fbcb.
• Klarskov N. Urethral pressure reflectometry. A method for simultaneous measurements of pressure and cross-sectional area in the female urethra. Dan Med J. 2012 Mar;59(3):B4412.
• Saaby ML, Klarskov N, Lose G. Urethral pressure reflectometry before and after tension-free vaginal tape. Neurourol Urodyn. 2012 Nov;31(8):1231-5. doi: 10.1002/nau.22239. Epub 2012 Mar 27.

Study record dates

Study Major Dates

• Study Start: November 1, 2015
• Primary Completion (Actual): October 1, 2016
• Study Completion (Actual): October 1, 2016

Study Registration Dates

• First Submitted: May 12, 2016
• First Submitted That Met QC Criteria: May 20, 2016
• First Posted (Estimate): May 25, 2016

Study Record Updates

• Last Update Posted (Actual): January 22, 2021
• Last Update Submitted That Met QC Criteria: January 4, 2021
• Last Verified: January 1, 2021

More Information

Terms related to this study

• Keywords: Faecal Incontinence
• Additional Relevant MeSH Terms: Digestive System Diseases; Gastrointestinal Diseases; Intestinal Diseases; Rectal Diseases; Fecal Incontinence
• Other Study ID Numbers: 2015GA004

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: individual patient data will not add any further information to the overall data