Pre- and Postoperative Rectal Manometric Assessment of Patients With Anorectal Malformations: Should We Preserve the Fistula?

BACKGROUND: Surgical correction of congenital anorectal malformations could be complicated by fecal incontinence. Some authors believe that preservation of the fistula is associated with improved outcome. Rectal manometry is a well-established method to evaluate postoperative functional outcome in these patients and can demonstrate successful transplantation of the fistula. OBJECTIVE: Herein, we report the results of our series of patients with anorectal malformations and an externally accessible fistula, who underwent pre- and postoperative rectal manometry studies. DESIGN: This is a prospective cohort study. SETTINGS: This study was conducted at a tertiary neonatal and pediatric surgical center. PATIENTS: Patients with anorectal malformations, who underwent preoperative rectal manometry of the fistula and postoperative rectal manometry of the neoanus between January 2002 and December 2011 were included. MAIN OUTCOME MEASURES: Pre- and postoperative rectal manometry results were compared by using paired t test or contingency tables (p values < 0.05). RESULTS: Twelve female patients with rectoperineal (n = 7, 58%) or rectovestibular (n = 5, 42%) fistula were treated by anterior sagittal anorectoplasty or minimal posterior sagittal anorectoplasty. Complete transposition of the fistula was achieved in all patients. Normal presence of rectoanal inhibitory reflex was demonstrated in all pre- and postoperative rectal manometry studies. There were no differences between pre- and postoperative rectal manometry in the length of the high-pressure zone (2.3 +/- 0.6 cm vs 2.5 +/- 0.8cm (p = 0.5)) and resting pressure (59.4 +/- 18.2 mm Hg vs 62.1 +/- 19.2 mm Hg (p = 0.62)). At a median follow-up of 665 days (range, 290-1165 days), all patients have voluntary bowel movements, with no incontinence or soiling. LIMITATIONS: This study is limited by its small sample size and by single-institution bias. CONCLUSION: Preoperative rectal manometry of rectoperineal or rectovestibular fistula showed the presence of functional anal structures within the fistula in all patients. We speculate that fistula-preserving surgery in patients with anorectal malformations is associated with improved bowel function outcome.