Impact of Internal Anal Sphincter Division on Continence Disturbance in Female Patients
Sthela M. Murad-Regadas, Francisco Sergio P. Regadas, Ricardo E. Dias Mont'Alverne, Graziela O. da Silva Fernandes, Milena M. de Souza, Nayane de A. Frota, David G. Ferreira- Gastroenterology
- General Medicine
BACKGROUND:
Few studies measured the pre-and postoperative anatomic and functional anal canal using 3-dimensional endoanal ultrasound and anal manometry, and correlated sphincter division with fecal incontinence, severity, and function.
OBJECTIVE:
Assess the incidence of fecal incontinence in patients who underwent internal anal sphincter division for anal fissure or intersphincteric anal fistula, and correlate severity of symptoms with percentage of divided muscle, anatomical measurements, and anal pressures.
DESIGN:
Prospective cohort study.
Settings:
Colorectal surgery unit, tertiary referral center.
PATIENTS:
Patients underwent clinical assessment using Cleveland Clinic Florida Fecal Incontinence score for severity of symptoms, manometry, and ultrasound.
MAIN OUTCOMES MEASURES:
Ultrasound measurements of length, percentage and angle of divided internal anal sphincter, and anterior external anal sphincter, posterior external anal sphincter plus puborectalis, and gap lengths.
RESULTS:
Sixty-three women (mean age, 44 years) were divided into 2 groups: 30 (48%) underwent fistulotomy for intersphincteric anal fistula and 33 (52%) underwent sphincterotomy for chronic anal fissure with high anal resting pressure. 46% experienced some measure of fecal incontinence after internal anal sphincter division. Incidence of fecal incontinence, severity of symptoms, and angle of the divided internal anal sphincter were similar between the groups. Length and percentage of the divided internal anal sphincter were significantly higher in the intersphincteric anal fistula. External anal sphincter and external anal sphincter plus puborectalis lengths were similar in both groups. Gap length was significantly longer in chronic anal fissure with high anal resting pressure.
LIMITATIONS:
Single-institution, exclusion of males.
CONCLUSION:
Fecal incontinence was reported in half of the patients who underwent internal anal sphincter division. Despite the greater length and percentage of internal anal sphincter division in patients who underwent fistulotomy, incidence and severity of fecal incontinence were similar in both groups. Three-dimensional endoanal ultrasound showed greater gap length in the sphincterotomy group, which may be functionally significant after division of the shorter internal anal sphincter, but with similar impact on fecal incontinence in both groups.