Assessment of brain activity during voluntary anal sphincter contraction: Comparative study in women with and without fecal incontinence.

BACKGROUND: Voluntary anal sphincter function is driven by an extended network of brain structures, most of which are still unknown. Disturbances in this function may cause fecal incontinence. The aim of this study was to characterize the cerebral areas involved in voluntary contraction of the anorectal sphincter in healthy women and in a group of patients with fecal incontinence by using a standardized functional magnetic resonance imaging (fMRI) protocol. METHODS: This comparative study included 12 healthy women (mean age 53.17 ± 4.93 years) and 12 women with fecal incontinence (56.25 ± 6.94 years). An MRI-compatible anal manometer was used to register voluntary external anal sphincter contraction. During brain fMRI imaging, participants were cued to perform 10-s series of self-paced anal sphincter contractions at an approximate rate of 1 Hz. Brain structures linked to anal sphincter contractions were mapped and the findings were compared between the 2 study groups. KEY RESULTS: There were no differences in the evoked brain activity between the 2 groups. In healthy women, group fMRI analysis revealed significant activations in medial primary motor cortices, supplementary motor area, bilateral putamen, and cerebellum, as well as in the supramarginal gyrus and visual areas. In patients with fecal incontinence, the activation pattern involved similar regions without significant differences with healthy women. CONCLUSIONS & INFERENCES: This brain fMRI-anorectal protocol was able to map the brain regions linked to voluntary anal sphincter function in healthy and women with fecal incontinence.

Does correlation exist between anorectal manometry and endoanal ultrasound findings in healthy subjects according to age?

BACKGROUND: different studies have demonstrated the correlation between anorectal manometry and endoanal ultrasonography data in patients with fecal incontinence, but there is no almost interest describing the same in healthy subjects according to age. AIMS: to study the possible correlation between anorectal manometry and endoanal ultrasonography data in a homogeneous group of healthy women, also according to age. MATERIAL AND METHODS: prospective observational study of a healthy subjects cohort (n=14). Homogeneous group of healthy volunteer women divided in 2 subgroups according to age. RESULTS: there was no proved correlation between the internal anal sphincter's measurement and the resting pressure in the whole sample as well as the analysis according to age. Neither there was any proved statistically significant correlation between the external anal sphincter´s thickness and the squeeze pressure, in the whole sample and by groups. CONCLUSIONS: it does not exist statistically significant correlation between the thickness of the sphincters and its function in a healthy subjects homogeneous group, neither in 2 groups according to age.