Introduction. Surgical treatment of obstruction of the upper urinary tract due to their recurrent extended strictures and obliterations remains a complex problem of modern urology.

Purpose. Conduct an analysis of our own experience of ureteral replacement graft with a graft of the oral mucosa with its extended strictures and obliterations.

Materials and methods. We observed 14 patients with this disease and the presence of severe comorbidity. Patients underwent replacement ureteroplasty using a graft of the oral mucosa, in 11 (78.6%) – complete (tubularization), in 3 (21.4%) – onlay. Seven (50%) patients underwent intervention in the upper third of the ureter and pelvic-ureteral junction, 5 (35.7%) in the lower part of the ureter, and 2 (14.3%) in the middle part. In 2 (14.3%) patients, laparoscopic plastic surgery was performed; in 12 (85.7%), the surgical manual was performed in an open way.

Results. A ureter defect requiring replacement was 5 to 9 cm (average 6.6 cm). In all cases, except for one (7.1%), lumbar muscle was used to improve vascularization of the buccal graft. Severe complications in according to Clavien-Dindo classification, as well as fatal outcomes, were absent. The observation period of patients ranged from 3 to 45 months (an average of 14.7 months). Over the entire period of observation of the ureter of stricture or obliteration recurrence in this group was not detected.

Findings. This operation can be regarded as the «second» line of surgical treatment of this pathology after endoscopic interventions and/or reconstructive operations using the tissues of their own upper urinary tract, with the impossibility of enteroplasty in patients with severe concomitant pathology