Incidence of sphincter defects in fecal incontinence: a prospective endosonographic study.

Study aim: To assess the incidence of endosonographic anal sphincter defects in a population of patients complaining of anal incontinence. Patients and methods: Seventy two consecutive patients (10 men, 62 women, mean age: 55 years) with anal incontinence underwent transanal sonography. In this series, 22 patients had a history of anal surgery (group I), while 50 patients (46 parous women, 4 men) had not been previously operated (group II). Results: Fifty patients (69.4%) had an anal sphincter defect identified on transanal sonography: 6 isolated internal sphincter defects (12%), 18 isolated external sphincter defects (36%) and 26 combined sphincter defects (52%). The incidence of sphincter defects was similar in the surgical and medical group (81.8% vs 64%, p > 0.05). All but one of the isolated internal sphincter defects were observed in group I. Among the 46 parous women of group II, the use of forceps was not associated with a significantly higher frequency of anal sphincter defects (72% vs 64%, p > 0.05). Conclusion: This study confirms the high incidence of endosonographic anal sphincter defects in patients with anal incontinence. Isolated lesions of the internal sphincter are mainly seen after anal surgery. In our group of parous women, the use of forceps did not increase the incidence of anal sphincter lesions. (C) 2000 Editions scientifiques et medicales Elsevier SAS.