A prospective observational study aimed to assess the efficacy and safety of Allium ureteral stent long-term indwelling in the treatment of ureteral stricture.

Inclusion Criteria:

1. Benign diseases: UPJ, ischemic injury caused by surgical separation, endoscopic surgery injury, heat injury by laser lithotripsy, infection (chronic inflammation, tuberculosis), peri-ureteral fibrosis caused by endometriosis, ureteral anastomotic stenosis after renal transplantation, ureteral fistula, multiple polyps;
2. Malignant diseases: ureteral anastomotic stricture after urinary diversion, stricture caused by compression of abdominal and/or pelvic tumors, stricture caused by urinary tract tumors, stricture caused by radiotherapy for colon or cervical cancer, ureteral fistula

Exclusion Criteria:

1. Combine with hypertonic neurogenic bladder (except for patients with long-term indwelling catheter)
2. Colon resection surgery patients -

Patients suffering from ureteral obstruction that require treatment.