Intraoperative ultrasound-assisted endoscopic treatment of primary intermediate and high-grade vesicoureteral reflux in children in a long-term follow-up

Background: Endoscopic treatment of vesicoureteral reflux (VUR) is an important minimally invasive surgical approach in patients undergoing surgical treatment of VUR. In our past experience, we observed that a bulking agent mound sagittal diameter of 10 mm is the main predictor of effectiveness of the procedure. Moreover we noticed that the use of intraoperative ultrasound, allows the surgeon to better identify the site, volume and shape of the bulking agent injected, finally reducing operative time. Objective: We aimed to evaluate if the intraoperative ultrasound assistance could definitively improve effectiveness of the endoscopic procedure. Methods: We retrospectively compared two series treated with endoscopic procedures for intermediate and high grade primary VUR, respectively without (series A) and with (series B) intraoperative ultrasound (IO-US). In all patients VCUG was performed to assess VUR grade and to verify resolution or VUR downgrading during the follow-up. Results: A total of 177 ureteric units were treated. Endoscopic procedures globally were effective in 68/96 ureters (70.8 %) in series A and in 68/81 ureters (83.9 %) in series B. No significant differences in effectiveness were observed comparing the series with regard to VUR grades, but a significant difference is shown (p < 0.05) when grouping grades III-V VUR. No significance in differences of volume injected were detected, but operative time was significantly lower in series B (27.5 min vs 19.6 min, p < 0.05). Mean sagittal mound diameter measured during cystoscopy in series B was 10.45 mm (range 8.5-14.2 mm). Discussion: The intraoperative ultrasound assistance during endoscopic treatment of VUR could represent a valid tool for surgeons to better identify location, volume and shape of the bulking agent. Furthermore, the use of an objective parameter of evaluation of the implant can overcome the subjective intraoperative evaluation of the implant itself, improving results for experienced surgeons and reducing the learning-curve for inexperienced ones. Conclusions: Results of endoscopic injection of bulking-agent can be improved with intraoperative ultrasound, allowing at the same time a significant reduction of operative time.