Immediate postpartum assessment of the anal sphincter by endovaginal ultrasound: An experimental study.

INTRODUCTION AND HYPOTHESIS: Obstetric anal sphincter injuries are frequently missed and carry a significant risk for the development of anal incontinence. Immediate postpartum endoanal ultrasound increases identification of these injuries but is rarely employed. We hypothesize that endovaginal ultrasound could be a feasible and easily available alternative sonographic tool to improve early diagnosis of anal sphincter tears. METHODS: We conducted a prospective experimental study including 160 primiparous women. Shortly after vaginal delivery, patients underwent clinical and sonographic perineal examinations. We analyzed the feasibility of anal sphincter assessment by endovaginal ultrasound and its potential contribution in the early diagnosis of anal sphincter injuries. RESULTS: Sonographic assessment of the anal sphincter was analyzable for 136 patients (85.0%). Causes of non-analyzability included air artifacts (6.9%), lack of distinction between the external anal sphincter and surrounding tissues (9.4%) and distortion artifacts (9.4%). Patients in the non-analyzable ultrasound subgroup were less likely to have delivered in a dorsal lithotomy position (62.5% vs. 85.3 %) and more likely to have had an episiotomy (33.3% vs. 14.0%), and their risk of sphincter injury was more frequently classified as "improbable" on clinical examination (91.7% vs. 61.0%). Ultrasounds were analyzable for 96.4% of patients clinically reported as having "possible" or "certain" sphincter injuries. The incidence of anal sphincter injury was 16.9% for clinical observation and 20.0% with associated sonographic examination. CONCLUSIONS: Endovaginal ultrasound could be used as a complementary tool in assessment of the anal sphincter in high-risk patients. Its feasibility and easy availability make this technique a promising tool for improving the management of anal sphincter tears.

Immediate postpartum assessment of the anal sphincter by endovaginal ultrasound: a new technical approach.

INTRODUCTION AND HYPOTHESIS: In this study we described a new technical approach to adapt endovaginal ultrasound scanning of the anal sphincter complex to the immediate postpartum period. METHODS: We analyzed the clinical and ultrasonographic examinations of 18 primiparous women presenting deep perineal tears with potential or clearly identified lesions of the anal sphincter. Potential anal sphincter lesion was defined as a second degree perineal tear extending close to the anal sphincter with exposition of its capsule or muscular fibers. We reported interesting ultrasonographic images explaining our technique in a video. RESULTS: We reported clinical and ultrasonographic features in nine cases of grade 2, four cases of grade 3a, four cases of grade 3b and one case of grade 3c perineal tears. The ultrasonographic examination confirmed the intact state of the anal sphincter complex in all patients with clinical grade 2 tears except one in which a grade 3b lesion was detected. We were not able to identify external anal sphincter lesions on ultrasound in any of the patients with clinical grade 3a tears. In patients with clinical grade 3b tears, the ultrasound confirmed the external anal sphincter lesion in all cases, but revealed additional involvement of the internal anal sphincter in 1 case (grade 3c). CONCLUSION: Immediate postpartum endovaginal ultrasound could be a promising technique to improve the management of perineal traumas after vaginal delivery.