Introduction. After buccal ureteroplasty of long stricture of ureteropelvic junction and proximal ureter, there is a risk of recurrent stricture and urinary stone formation, requiring endoscopic
procedure.
Aim. To evaluate the possibility of performing ureteroscopy (URS) in patients after onlay ureteroplasty, as well as to study its results and efficiency.
Materials and methods. Buccal ureteroplasty was performed in 30 patients who had previously undergone endoscopic and reconstructive procedures on the upper urinary tract. In 18 (60.0%) of them, stricture developed after pyeloplasty, in 10 (33.4%) after retrograde lithotripsy for the upper ureteral stone, in 1 (3.3%) after laparoscopic excision of a parapelvic cyst complicated by an injury of UJO. In addition, in 1 (3.3%) patient, stenosis of the upper third of the right ureter was caused by retroperitoneal fibrosis. The indication for URS in 7 (23.3%) cases was urolithiasis. Three patients had a dense stone measuring 1.0 cm in the lower calyx, three more had a recurrent stone after previous procedures, and one had encrusted nephrostomy. Rigid URS with laser fragmentation was performed in 3 (10.0%) cases. In two patients, the indication for endoscopic procedure was a dense stone in the upper third of the ipsilateral ureter. The patient with encrusted nephrostomy pigtail underwent lithotripsy with drainage removal. Retrograde laser lithotripsy using flexible ureteroscope was performed in 4 patients (13.3%). Rigid URS with buccal graft mucosa biopsy was done in 5 cases (16.7%) 12 and 24 months after reconstruction.
Results. Endoscopic procedures for urolithiasis were effective in all patients. The average time was 45.0±28 min. During URS, hematuria developed in 1 of 14 patients at a late stage, but visibility allowed completing an intervention. High fever was observed in 2 patients (14.3%) postoperatively. One of them underwent rigid URS with lithotripsy of incrusted pigtail of nephrostomy tube, and he also had bleeding. Laser lithotripsy using flexible ureteroscope was performed in another case. Both patients had stage II complications according to Clavien, requiring conservative therapy.
Conclusion. After buccal ureteroplasty, URS should not be a routine study, except for patients with recurrent urolithiasis or ureteral strictures.

Keywords: retrograde intrarenal surgery using flexible ureteroscope, buccal ureteroplasty, lithotripsy, ureteroscopy, stricture, ureter