Use of 3D Ultrasound to Predict Anal Sphincter Defects

Injury to the muscles of the back passage (anal canal) is a relatively common problem. This injury can result in problems with bowel control later in life and usually occurs during vaginal childbirth (commonly referred to as 3rd and 4th degree perineal tears). Currently women who have sustained injury to the muscles of the back passage undergo an ultrasound scan by inserting a probe 3 to 4 cms into the back passage. This helps to check if the muscle of the back passage has healed i.e is intact or has a defect. The investigators would like to establish whether a 3D ultrasound scan probe placed outside the vagina can identify the defects and hence avoid inserting the probe into the back passage. In addition to getting the above information using 3D ultrasound scan, the investigators would also like to identify injuries to the pelvic floor muscle (levator ani) in these patients. Which can be diagnosed using the 3D ultrasound probe placed outside the vagina (perineum). Women who sustain injury to this muscle are known to develop prolapse later on in life.

Study Overview

• Status: Completed
• Conditions: Obstetric Anal Sphincter Injury
• Intervention / Treatment: Other: Pelvic Floor Ultrasound

• Study Type: Observational
• Enrollment (Actual): 250

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: Female

• Sampling Method: Probability Sample

Study Population

Women sustained anal sphincter injury during childbirth being followed up ante or postpartum

Description

Inclusion Criteria:

• Women who sustained an obstetric anal sphincter injury referred to the perineal clinic

Exclusion Criteria:

• None

Study Plan

How is the study designed?

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Diagnostic test accuracy of 3D endovaginal (EVUS) and transperineal ultrasound (TPUS) for diagnosing Obstetric Anal Sphincter injurieS (OASIS)	To calculate the diagnostic test characteristics (e.g sensitivity, specificity, positive predictive value, negative predictive value and likelihood ratio) to enable comparison of three methods of ultrasound assessment of the anal sphincter following sphincter injury after vaginal delivery	3 months Postpartum

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Prevalence of Levator Ani Muscle Injury in women who sustained Obstetric Anal Sphincter Injury	To calculate the prevalence of LAM avulsion in women with OASIS	3 months Postpartum

Collaborators and Investigators

• Sponsor: Croydon University Hospital

Publications and helpful links

General Publications

• Taithongchai A, van Gruting IMA, Volloyhaug I, Arendsen LP, Sultan AH, Thakar R. Comparing the diagnostic accuracy of 3 ultrasound modalities for diagnosing obstetric anal sphincter injuries. Am J Obstet Gynecol. 2019 Aug;221(2):134.e1-134.e9. doi: 10.1016/j.ajog.2019.04.009. Epub 2019 Apr 11.

Study record dates

Study Major Dates

• Study Start: August 1, 2013
• Primary Completion (Actual): August 1, 2015
• Study Completion (Actual): August 1, 2015

Study Registration Dates

• First Submitted: September 8, 2015
• First Submitted That Met QC Criteria: January 12, 2016
• First Posted (Estimate): January 14, 2016

Study Record Updates

• Last Update Posted (Estimate): January 14, 2016
• Last Update Submitted That Met QC Criteria: January 12, 2016
• Last Verified: January 1, 2016

More Information

Terms related to this study

• Keywords: Ultrasound diagnosis; Obstetric anal sphincter injury,
• Other Study ID Numbers: 13/LO/0232