Manometric findings in relation to functional outcomes in different types of anorectal malformations

Abstract

Aims: To compare anorectal manometry (AM) in patients with different types of anorectal malformations (ARMs) in relation to functional outcomes.

Methods: A single-institution, cross-sectional study. After ethical approval, all patients ≥7years old treated for anterior anus (AA), perineal fistula (PF), vestibular fistula (VF), or rectourethral fistula (RUF) from 1983 onwards were invited to answer the Rintala bowel function score (BFS) questionnaire and to attend anorectal manometry (AM). Patients with mild ARMs (AA females and PF males) had been treated with minimally invasive perineal procedures. Females with VF/PF and males with RUF had undergone internal-sphincter saving sagittal repairs.

Results: 55 of 132 respondents (42%; median age 12 (7-29) years; 42% male) underwent AM. Patients with mild ARMs displayed good anorectal function after minimally invasive treatments. The median anal resting and squeeze pressures among patients with mild ARMs (60 cm H2O and 116 cm H2O respectively) were significantly higher than among patients with more severe ARMs (50 cm H2O, and 80cm H2O respectively; p≤0.002). The rectoanal inhibitory reflex was preserved in 100% of mild ARMs and 83% of patients with more severe malformations after IAS-saving sagittal repair. The functional outcome was poor in 4/5 patients with an absent RAIR (BFS≤11 or antegrade continence enema-dependence). Rectal sensation correlated significantly with the BFS.

Conclusions: Our findings support the appropriateness of our minimally invasive approaches to the management of mild ARMs, and IAS-saving anatomical repairs for patients with more severe malformations.

Level of evidence: III.

Keywords: Anorectal malformations; Anorectal manometry; Bowel function; Fecal continence; Internal anal sphincter.