Research Results

The CAPS Imaging Study: Anatomic Characterization of the External/Internal Anal Sphincter at Six Months Postpartum

1) HE Richter, JR Fielding, CS Bradley, VL Handa, P Fine, MP Fitzgerald, A Visco, A Wald, C Hakim, JT Wei, AM Weber for the Pelvic Floor Disorders Network, Endoanal ultrasound findings and fecal incontinence symptoms in women with and without recognized anal sphincter tears. Obstetrics and Gynecology 2006; 108: 1394-1401.

One possible cause of fecal incontinence (the uncontrolled loss of liquid or solid stool) in young, healthy women is vaginal delivery, especially when the woman had a tear in the anal sphincter (muscles surrounding the anal opening) at the time of the vaginal delivery. Ultrasound can be used to see if there is a “gap” in either the external anal sphincter (the outer muscle) or the internal anal sphincter (the inner muscle). The purpose of this study was to determine if ultrasound can be used to identify more gaps or damage 6-12 months after vaginal delivery in women that had a sphincter tear at the time of delivery of their first baby than in women who did not have a sphincter tear. We also wished to see if these ultrasound findings were associated with fecal incontinence and its severity.

The study found that:

• There were more gaps seen in women that had a sphincter tear at the time of vaginal delivery compared to those women without a tear at delivery or women who had a cesarean delivery without labor.
• Increased severity of fecal incontinence was seen in women with gaps in the internal anal sphincter. Greatest severity was seen in women with gaps in both the internal and external sphincters.

The use of ultrasound in the evaluation of women with fecal incontinence may help to determine whether a gap is present in the anal sphincter that may be treated by surgical repair especially when the woman had a sphincter tear at the time of vaginal delivery.