Absence of a rectocele may be correlated with reduced internal anal sphincter function in patients with rectal intussusception and fecal incontinence

Abstract

Purpose: Fecal incontinence (FI) is common in patients with rectal intussusception (RI), although the mechanism behind its formation is unclear. Recent data indicate that a reduction in internal sphincter tone may cause FI, which becomes notable with increasing RI levels. However, the roles of other anatomical abnormalities in anal function remain unclear. This study assessed the relationships between various pelvic floor abnormalities and anal sphincter function in patients with RI and FI. Methods: Data for patients with RI, collected in a prospective pelvic floor database, were assessed retrospectively. All women with FI, without anal sphincter defect, were included. Data on anorectal physiology and evacuation proctography were analyzed. Results: Of 397 patients with RI, 85, who had predominantly passive FI, met the inclusion criteria. Maximum resting pressure (MRP) was significantly lower in patients with rectoanal intussusception (RAI) than in those with rectorectal intussusception (RRI) [51.1 (17.9–145.8) vs. 70.7 (34.7–240.6) cmH2O, P = 0.007]. Moreover, MRP was significantly lower in RI patients without rectocele than in RI patients with rectocele [50.1 (17.9–111.0) vs. 69.9 (34.7–240.6) cmH2O, P < 0.0001]. Regression analysis showed that RAI rather than RRI and RI without rectocele rather than RI with rectocele were predictive of decreased MRP. However, no variable was significantly associated with decreased maximum squeeze pressure on multivariate analysis. Conclusion: In addition to an advanced level of intussusception, the absence of a rectocele may be correlated with reduced internal anal sphincter function in patients with RI and FI.