Implant of Self-Expandable Artificial Anal Sphincter in Fecal Incontinent Patients Improves External Anal Sphincter Contractility.

BACKGROUND External anal sphincter contractility significantly contributes to control the stools passage. An artificial anal sphincter placed into the intersphincteric space is a safe and effective procedure to treat fecal incontinence, even if its mechanism of action has not been fully elucidated. OBJECTIVE The aim of this study was to evaluate external anal sphincter contractility changes after a self-expandable hyexpan prostheses was implanted into the intersphincteric space of the anal canal and clinical outcomes compared. DESIGN Prospective clinical study. SETTINGS The study was conducted at a University teaching hospital. PATIENTS Consecutive patients affected by fecal incontinence for at least 6 months, after failure of conservative treatment. INTERVENTIONS All patients underwent 10 prostheses implantation, and were examined pre- and postoperatively by endoanal ultrasound and anorectal manometry. MAIN OUTCOME MEASURES Fecal incontinence symptoms were assessed by severity scores. The external anal sphincter muscle-tension was calculated using a specific equation. RESULTS Thirty-nine patients (34 females; median age 68 years) were included in the study; no morbidity was registered. After a median follow-up period of 14 months, both the median maximum voluntary squeeze pressure and the median inner radius of the external anal sphincter significantly increased. A statistically significant increase of external anal sphincter muscle tension was detected. A decrease of any fecal incontinence symptom and an improvement in severity scores were observed at the last follow-up examination. The external anal sphincter contractility was significantly higher in patients reducing incontinence episodes to solid stool by more than 50% and improving ability to defer defecation for more than 15 minutes. LIMITATIONS Single-center experience; relatively small and heterogeneous sample size; patients with a potentially more severe disease because our institution is a referral center; absence of quality of life evaluation. CONCLUSIONS Artificial anal sphincter implantation improved the external anal sphincter muscle-tension; there was a positive correlation between its increase and the clinical outcome. See Video Abstract at http://links.lww.com/DCR/B468 .