Assessment of anal sphincter distensibility following the STARR procedure: a pilot study

Aim: The STARR (Stapled Trans-Anal Rectal Resection) procedure consists of a surgical correction of symptomatic rectocele refractory to medical treatment, involving anal dilatation. The aim of the study was to determine the impact of the STARR procedure on anal distensibility using EndoFLIP^® device.Methods: All female patients with a minimal rectocele of 3 cm and with symptoms of obstructed defecation syndrome (ODS) refractory to medical treatment were included prospectively. Patients with previous anal incontinence were not included. Wexner, ODS and Kess scores were recorded. Endoanal ultrasounds and EndoFLIP^® measurements were performed pre-surgery and 3 months following the STARR procedure. The distensibility index (DI) at 40 mL of inflation at rest was the primary study endpoint.Results: Seven patients (median age: 52.5, range: 44-62) were included between 2014 and 2017. The DI after surgery was the same as the pre-surgery DI. No patient developed symptoms of faecal incontinence or urge to defecate in the three months following the STARR procedure. All patients reported an improvement in their ODS and Kess scores three months after the STARR procedure. No anal sphincter defects were detected by endoanal ultrasound.Conclusion: Anal dilatation did not appear to alter anal distensibility in patients with a normal anal function before the STARR procedure.