VP62.14: The reproducibility of ultrasonographic findings of rectosigmoid endometriosis among examiners with different level of expertise

To analyse the reproducibility of ultrasonographic (US) findings of rectosigmoid endometriosis among examiners with different level of expertise using stored 3D volumes of posterior compartment of the pelvis as a part of SANABA (Sardinia-Navarra-Barcelona) collaborative study. Six examiners in three academic Department of Obstetrics and Gynecology, with different levels of experience and blinded to each other, evaluated 60 stored 3D volumes from posterior compartment of the pelvis and looked for the presence or absence of features of rectosigmoid endometriotic lesions defined as an irregular hypoechoic nodule with or without hypoechoic foci at the level of the muscularis propria of the anterior wall rectum sigma. Multiplanar view and virtual navigation were used. All examiners had to assess the 3D volume of posterior compartment of the pelvis and classify it as present or absent. To analyse intraobserver and the interobserver agreement each examiner performed the assessment twice with a two-week interval between the first and second assessments. Reproducibility was assessed calculating the weighted Kappa index. Intraobserver reproducibility was moderate to good for all observers (Kappa index ranging from 0.46 to 0.96). Also the diagnostic accuracy of each reader was good with sensitivities ranging from 94% to 76% and specificities from 95% to 63% partially depending of the operator's experience. Interobserver reproducibility was fair to moderate (Kappa index range: 0.53-0.39). The typical US sign of rectosigmoid endometriosis are reasonably reproducible among observers with different level of expertise when assessed in stored 3D volumes. This study was partly supported by Fondazione di Sardegna grant F74I19001010007.