Role of Postoperative Renal Ultrasound in Identifying Ureteral Injury despite Normal Intraoperative Jet Flow

Abstract

Objective: This study evaluated the diagnostic utility of early postoperative renal ultrasound in detecting ureteral injury in patients who had undergone total laparoscopic hysterectomy (TLH) for benign indications, despite documented normal intraoperative ureteral jet flow on cystoscopy. Materials and Methods: In this retrospective cohort study at a high-volume tertiary center, data from 3,170 patients who underwent TLH between January 2022 and October 2025 were analyzed. Inclusion required normal bilateral ureteral jet flow on routine intraoperative cystoscopy, a renal ultrasound within the first 24 postoperative hours, and at least 30 days of clinical follow-up. The primary outcome was the diagnostic yield of postoperative ultrasound for identifying ureteral injuries not apparent during surgery. Injuries were confirmed by advanced imaging or surgical exploration. Results: The overall ureteral injury rate was 0.79% (n=25). Of these injuries, eight were diagnosed intraoperatively, while seventeen occurred despite documented normal bilateral ureteral jet flow during the procedure. Among the latter group, renal ultrasonography performed on postoperative day 1 detected 14 injuries, representing 56% of all injuries. Three injuries (12%) presented later, around postoperative day 10, and were not identified on initial imaging. Early postoperative ultrasonography demonstrated good sensitivity and a high negative predictive value as a screening tool. Comparison with preoperative baseline imaging enhanced diagnostic performance in identifying new-onset obstruction, particularly newly developed pelviectasis. Conclusion: Normal intraoperative ureteral jet flow does not preclude ureteral injury, particularly those with delayed presentation, such as thermal damage. Early postoperative renal ultrasonography is a valuable non-invasive screening tool that identifies a significant proportion of injuries missed by cystoscopy alone. Comparative evaluation of routine postoperative ultrasonography with preoperative imaging may provide a meaningful contribution to the early diagnosis of ureteral injury following TLH.