LAUSR

Study Objective To externally and temporally validate the Ultrasound Based Endometriosis Staging System (UBESS) to predict the level of complexity of laparoscopic surgery for endometriosis. Design Multi-center retrospective diagnostic accuracy study between 2016 and 2018. Setting Four different centers with advanced ultrasound and laparoscopic services were recruited. Patients or Participants Patients with suspected endometriosis who required surgery (laparoscopic excision of endometriosis). Interventions UBESS I, II and III were correlated with the Royal College of Obstetricians and Gynaecologists (RCOG) surgical stages 1, 2 and 3. Comparison between temporal and external sites as well as each site was performed in terms of the diagnostic accuracy of UBESS. Measurements and Main Results 294/317 women were included in the final analysis. UBESS overall accurately classified 80%, 71% and 60% of women to RCOG levels 1, 2 and 3 respectively (Table 1). When ureterolysis without bowel surgical cases (n=54) were excluded, the sensitivity of UBESS to correctly classify RCOG level 3 increased from 60% to 96.4% (p Conclusion UBESS externally validated did not perform as well as expected. When however the cases of ureterolysis (RCOG 3) in the presence of a normal ‘deep endometriosis’ scan were excluded, the performance of UBESS improved dramatically. These findings justify the search for other ultrasound markers to predict superficial pelvic side wall disease.