Poor outcome of sphincter repair: an evacuation problem?

Colorectal transport in idiopathic fecal incontinence has scarcely been studied, and it remains to be investigated in patients with fecal incontinence and anal sphincter lesion. The aim of the present study was to compare colorectal transport during defecation in patients with idiopathic fecal incontinence and patients with fecal incontinence due to anal sphincter lesions with transport in healthy volunteers.

Five women with idiopathic fecal incontinence (median age 72 years, range: 58-78 years) and five women with an obstetric sphincter lesion (median age 42 years, range: 28-63 years), four of whom had had previous anal sphincter repair, were compared with nine healthy female volunteers (median age 53 years, range 32-57 years). Colorectal scintigraphy was performed to assess colorectal emptying at defecation as well as segmental antegrade and retrograde transport during defecation. Segmental colorectal transit times were determined using radio-opaque markers.

Median colorectal emptying time at defecation was significantly lower in the sphincter lesion group compared with the healthy volunteers (P = 0.009). At defecation, median antegrade transport time from the ascending colon was significantly lower in the sphincter lesion group than in the healthy group (P = 0.02). The median segmental transit time from the rectosigmoid colon was higher in the group with a sphincter lesion than in the healthy group (P = 0.05). There were no statistically significant differences between the group with idiopathic fecal incontinence and the healthy volunteers.

Patients with fecal incontinence due to sphincter lesions, but not those with idiopathic fecal incontinence, have reduced transport from the cecum/ascending colon and from the rectosigmoid colon at defecation.