Clinical trial NCT02782377: Evaluation of the Rectal Reflex Using Anal Acoustic Reflectometry
Official title: Evaluation of the Rectal Reflex Using Anal Acoustic Reflectometry
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Pelvic Floor Dysfunction
Keywords: Faecal Incontinence
Obstructive Defaecation
Rectal Prolapse
Lead sponsor: Manchester University NHS Foundation Trust
Sponsor class: OTHER_GOV
First posted: 2016-05-25
Enrollment: 40
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: COHORT
Time perspective: PROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Patients presenting to the pelvic floor clinic and neurogastroenterology with symptoms of pelvic floor dysfunction

Brief summary: Anal Acoustic Reflectometry (AAR) is a reliable and reproducible 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. In previous studies AAR has shown promise in the assessment of faecal incontinence and, that unlike manometry, it has been able to distinguish between different types of incontinence.

The Recto-anal Inhibitory Reflex (RAIR) is a normal response when the rectum fills with faeces, fluid or air, whereby there is a change in the pressures within the anal canal to determine the type of contents. This can be absent or altered in patients who have difficulty in opening their bowels. The RAIR is currently measured by anal manometry using a 4.9mm catheter, resulting in an anal canal which is already partially opened prior to the measurement, and potentially distorted.

AAR is considered a catheter free technique as the balloon has a cross-sectional area of only 0.4mm2 when collapsed. The investigators propose to measure the RAIR using a 1.7mm diameter catheter alongside the AAR balloon to determine the effect that its placement has on the recorded parameters of AAR. This aims to improve our understanding of the opening and closing of the anal canal in response to distension of the rectum.


Eligibility criteria: Inclusion Criteria:

1. Adults over 18 years old
2. Have capacity to consent to the study
3. Patients with pelvic floor dysfunction.

Exclusion Criteria:

1. Minors under the age of 18 years old
2. Patients who lack capacity to consent
3. Patients with known rectal tumours and proctitis
4. Asymptomatic patients

Primary outcomes:
measure: Opening Pressure
timeFrame: during single study visit- measurement taken prior to balloon inflation and post balloon inflation
measure: Opening Elastance
timeFrame: during single study visit- measurement taken prior to balloon inflation and post balloon inflation
measure: Closing Pressure
timeFrame: during single study visit- measurement taken prior to balloon inflation and post balloon inflation
measure: Closing Elastance
timeFrame: during single study visit- measurement taken prior to balloon inflation and post balloon inflation
measure: Hysteresis
timeFrame: during single study visit- measurement taken prior to balloon inflation and post balloon inflation
Secondary outcomes:
Other outcomes:
Locations:
city: Manchester
country: United Kingdom
facility: University Hospital of South Manchester
state: Greater Manchester
Study officials:
affiliation: University Hospital of South Manchester
name: Karen J Telford, MBChBMDFRCS
role: STUDY_CHAIR
References:
citation: 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.
citation: 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.
citation: 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.
citation: 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.
citation: 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.
citation: 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.
citation: Cheeney G, Nguyen M, Valestin J, Rao SS. Topographic and manometric characterization of the recto-anal inhibitory reflex. Neurogastroenterol Motil. 2012 Mar;24(3):e147-54. doi: 10.1111/j.1365-2982.2011.01857.x. Epub 2012 Jan 11.
citation: Heywood NA, Sharma A, Kiff ES, Klarskov N, Telford KJ. Placement of a fine-bore rectal balloon catheter in the anal canal does not affect anal sphincter pressures: improving our understanding of physiological function with anal acoustic reflectometry. Colorectal Dis. 2020 Nov;22(11):1626-1631. doi: 10.1111/codi.15300. Epub 2020 Aug 30.
citation: Heywood NA, Sharma A, Kiff ES, Klarskov N, Telford KJ. A novel method for measurement of the recto-anal inhibitory reflex using anal acoustic reflectometry. Colorectal Dis. 2020 Nov;22(11):1632-1641. doi: 10.1111/codi.15110. Epub 2020 Sep 23.