Do Changes in Anal Sphincter Anatomy Correlate With Anal Function in Women With a History of Vaginal Delivery?

Abstract

-Objectives -To evaluate anal sphincter anatomy using three-dimensional ultrasonography (3-DAUS) in incontinent women with vaginal delivery, correlate anatomical findings with symptoms of fecal incontinence and determine the effect of vaginal delivery on anal canal anatomy and function. Methods -Female with fecal incontinence and vaginal delivery were assessed with Wexner's score, manometry, and 3DAUS. A control group comprising asymptomatic nulliparous was included. Anal pressure, the angle of the defect and length of the external anal sphincter (EAS), the anterior and posterior internal anal sphincter (IAS), the EAS + puborectal and the gap were measured and correlated with score. Results -Of the 62, 49 had fecal incontinence and 13 were asymptomatic. Twenty five had EAS defects, 8 had combined EAS+IAS defects, 16 had intact sphincters and continence scores were similar. Subjects with sphincter defects had a shorter anterior EAS, IAS and longer gap than women without defects. Those with a vaginal delivery and intact sphincters had a shorter anterior EAS and longer gap than nulliparous. We found correlations between resting pressure and anterior EAS and IAS length in patients with defects. Conclusions -Fecal incontinence symptoms did not correlate with anal pressures and anal sphincter anatomy changes, but women with sphincter defects have shorter anterior EAS and IAS and a longer gap.

Innervation asymmetry of the external anal sphincter in aging characterized from high‐density intra‐rectal surface EMG recordings

“…The inclusion of multiparous females should not be a concern. Studies have examined the effect of vaginal deliveries on EAS anatomy, and did not find a significant difference between parous and nulliparous women in subjects without childbirth‐related EAS trauma …”

Three‐dimensional high‐resolution anorectal manometry: does it allow automated analysis of sphincter defects?

“…Currently, EUS is considered to be the gold standard for assessing sphincter defects in the anal canal, but three‐dimensional EUS (3D‐EUS) has recently been developed. The 3D‐EUS probe collects longitudinal and axial data simultaneously, allowing measurement of the length, thickness, area and volume of a sphincter defect . A comparison between 3D‐HRAM and this new EUS technique for the diagnosis of a sphincter defect might be more appropriate for correlating manometric reconstructions with anatomical data.…”

3T external phased-array magnetic resonance imaging in detection of obstetric anal sphincter lesions: a pilot study

“…As postpartum FI could result from other causes such as perineal nerve injury, imaging of the sphincter musculature is required to adequately diagnose possible residual sphincter injuries. Clinical evaluation alone is not reliable enough in detecting external anal sphincter (EAS) lesions (9)(10)(11)(12). Upon diagnosing a ROASI, patients may be treated surgically with a secondary sphincteroplasty (13).…”