Aim of the study: to study the long-term outcomes of the endoprosthesis using the nitinol stent for the ureter obstruction.

Materials and methods. Implantation of the nitinol stents was performed in 48 patients with recurrent strictures of upper urinary tract (n=30) and tumor obstruction of the ureters (n=18). Among them 26 were male patients, 22 – female, age range was 28-75 years. Nineteen patients had the extended strictures of the abdominal ureter, 6 – of pyeloureteral junction (PUJ), 4 –the strictures of the ureter of transplanted kidney, and 1 – the stricture of the ureterocalicoanastomosis after the Neyvert operation. The causes of stenosis were rectal tumor in 6 patients and uteral cervix cancer in 11 patients. In one female patient with BournevillePringle disease metallic prosthesis was implanted into the PUJ of the single right kidney.

Results.The passage through the upper tract was restored in all patients. Postoperatively hematuria was evident in 4, recurrence of chronic pyelonephritis in 3 patients. The long-term outcomes (follow-up range 8-65 months) were good in 31 (64.6%) and satisfactory in 13 (27.1%) of patients. Unsatisfactory results could be reported in 4 cases (8.3%) and were related to the obstruction of the prosthesis with proliferative tissue. In the BournevillePringle disease patient re-obstruction was detected 16 months after the procedure due to the angiolipomatose nodes. Therefore a second nitinol stent was placed retrogradely.

Conclusions. In long and recurrent ureteral strictures after the failed plastic surgery or contraindications to the surgery nitinol stent placement could be a procedure of choice.