Reasons for repeated or staged operations for megaureter in children and measures for their prevention.

Introduction. The second most common pathology of the ureterovesical segment, after vesicoureteral reflux (VUR), is megaureter. At the moment, it is necessary to optimize the approach to performing various types of surgical interventions in children with megaureter. The question of the timing and indications for surgery, their number and the sequence of treatment stages remains open. The aim: to analyze the causes of repeated surgical interventions for megaureter and their prevention. Materials and methods. In the pediatric uroandrology department of the N. Lopatkin Scientific Research Institute of Urology and Interventional Radiology – Branch of the National Medical Research Radiological Centre of the Ministry of Health of Russian Federation, pneumovesiscopic reimplantation of the ureter (UR) according to Cohen was performed in 26 repeated patients over 9 years. 52 interventions were recorded before pneumovesicoscopic UR. 4 (15.4%) patients were previously operated on at a research institute, 4 (15.4%) at the place of residence and then received staged treatment at the N. Lopatkin Scientific Research Institute of Urology and Interventional Radiology – Branch of the National Medical Research Radiological Centre of the Ministry of Health of Russian Federation, 18 (69.23%) patients at the place of residence. Patients underwent from 1-6 surgical interventions, the average value was 2 interventions per 1 patient. Ureteral plication was required in 7 patients. In rare cases, megaureter was combined with ureterocele, duplication of the upper urinary tract and neurogenic bladder dysfunction. Results and Discussion. We combined the reasons for repeated surgical interventions into two blocks: 1inadequate drainage of the ureter, requiring repeated manipulations, including under anesthesia; 2 – complicating factors affecting the quality of the formation of ureterocystoanastomosis, surgical errors in the reimplantation technique and tactical errors that can lead to VUR or obstruction requiring re-operation. The use of original methods: intravesical plication of the ureter, fixation of the ureter at two levels (the entry point of the ureter into the bladder and in the area of the neoostium) is used to increase the length of the submucosal tunnel and create a better anti-reflux mechanism. Conclusion. Understanding the causes of possible complications of ureteral reimplantation allows you to more carefully carry out the stages of the operation, pay attention to key points and improve the results of megaureter correction.