Endosonographic assessment of postpartum anal sphincter injury using a 120 degree sector scanner

Obstetric injury is the principal cause of faecal incontinence in semen. We describe use of a 120 degrees sector ultrasound probe to assess integrity of the anal sphincters in primigravid women, Eighty-eight women were successfully studied 6 weeks following vaginal delivery. Anal vector manometry and pudendal nerve studies were abnormal in 54 (61%), of whom 41 (71%) were symptomatic (urgency of defaecation, incontinence to flatus or faeces). The sonographic pattern of the anal sphincters described with a 360 degrees probe was reproduced. Forty-eight abnormal scans were reported by two radiologists with a kappa statistic of 0.65, Sphincter defects were found in 11 asymptomatic women, We conclude that anal endosonography has an important role screening for and diagnosis of postpartum anal sphincter defects. Use of a 120 degrees sector ultrasound probe may prove a cost-effective means of increasing the availability of this technique.