Objectives-To evaluate the agreement between two-dimensional transvaginal ultrasound (2D-TVUS) and transperineal tomographic ultrasound imaging on three-dimensional (3D) volume in diagnosing levator ani muscle (LAM) avulsion of postpartum women. Furthermore, we tested the repeatability of the 2D-TVUS in measuring the LAM thickness.Methods-A retrospective study was performed using the data sets from postpartum women. One doctor measured the thickness of the LAM on the images at the attachment to the arcus tendinous levator ani and the middle part using the 2D-TVUS ultrasound data sets of postpartum women. These women were examined twice, at 42-56 days and 3-6 months postpartum. Intra-observer repeatability was expressed using intraclass correlation coefficients (ICCs). The other doctor judged whether there was avulsion in the LAM on the 2D-TVUS and transperineal tomography imaging on the 3D volume. The inter-method agreement was determined using Cohen's kappa coefficient (k).Results-Thickness measurements of the middle part and attachment of the LAM by 2D-TVUS showed excellent and good intra-observer repeatability (ICC 0.84; 95% CI, 0.76-0.88, and ICC 0.74; 95% CI, 0.67-0.84, respectively). The overall agreement was 92% (Cohen's kappa was 0.79) between 2D-TVUS and transperineal tomographic imaging. Compared to transperineal tomographic imaging in the diagnosis of LAM avulsion, the diagnostic sensitivity of 2D-TVUS was 91.7%, the specificity was 92.1%.Conclusions-The 2D-TVUS technique, a simple and reproducible method for assessing LAM avulsion, may be helpful as a screening tool for LAM avulsion of postpartum women.

Rationale: Persistent urogenital sinus (PUG) with uterus didelphys and double vagina is a rare urogenital anomaly. The diagnosis is based on magnetic resonance examination and cystoscopy. To the best of our knowledge, there is no literature report of PUG diagnosed by ultrasound alone. Patient concern: A 23-year-old woman presented with atypical menstruation and recurrent hematuria for 13 years and recurrent lower abdominal pain for 12 years. Diagnosis: PUG was diagnosed through multiple ultrasound modalities, including transabdominal 2-dimensional ultrasound, transrectal bi-plane high-frequency ultrasound, and contrast-enhanced ultrasound. We diagnosed this malformation preoperatively by accurately measuring the length of urethra and common channel through multimodal ultrasound imaging. Interventions: Urethra separation and reconstruction, vaginal pull-through and artificial vaginoplasty, and bilateral hysterosalpingectomy were performed. Outcomes: The postoperative course was uneventful. She was urinating normally after half a year and used continuous vaginal dilatation to avoid stenosis. Lessons: PUG associated with uterus didelphys and double vagina is an extremely rare malformation of the reproductive system. Multimodal ultrasound imaging can be used to diagnose this malformation preoperatively clearly and to accurately measure the length of urethra and common channel, providing an imaging basis for preparing an operative plan.