Reproducibility of three-dimensional ultrasound diagnosis of congenital uterine anomalies.

Objective: To examine the reproducibility of the diagnosis of congenital uterine anomalies and the repeatability of measurements of uterine cavity dimensions using three-dimensional (3D) ultrasound.

Methods: The reproducibility of diagnosis of congenital uterine anomalies was examined by re-slicing stored 3D ultrasound volumes. Each data set was evaluated by two independent observers. Assessment of uterine morphology was performed in a standardized plane, with the interstitial portions of the Fallopian tubes used as reference points. Additionally, in 35 cases of congenital uterine anomalies the width of the uterine cavity (W), fundal distortion (F) and the length of unaffected uterine cavity (C) were measured. Intraobserver and interobserver variabilities were evaluated by each observer performing all three measurements twice.

Results: Eighty-three 3D ultrasound volumes were examined. Both operators classified 27 uteri as normal, 33 as arcuate, 19 as subseptate and three as unicornuate. A single case of uterine anomaly was described as arcuate uterus by one operator and subseptate by another (kappa 0.97). The intraobserver variability for each of the three measurements (W, F and C) was satisfactory with limits of agreement ranging from +/-1.43 to +/-2.51 mm. The examination of the interobserver variability showed no significant differences between the two observers (F = 0.484, P > 0.05).

Conclusion: 3D ultrasound is a reproducible method for the diagnosis of congenital uterine anomalies and for the measurement of uterine cavity dimensions.