The damage to the ureter after flexible mirror surgery is larger and larger, which may cause painful urination and hematuria, hydronephrosis or perforation, septic stenosis and other aspects of the disease. 1. Painful urination and hematuria: Because the minimally invasive ureteroscopic surgery may cause damage to the ureter or the tissues around the stone, resulting in painful urination or even hematuria, but generally it has little effect on the patient and can be recovered in a short time. 2. Hydronephrosis or perforation: After having the flexible ureteroscopic surgery to remove the stone, hydronephrosis or perforation may occur in the cavity originally occupied by the stone. 3. Septic stenosis: Postoperative infection in some patients may lead to septic stenosis of the ureter and damage the surrounding tissues. It is suggested that patients need to go to regular hospitals for treatment under the consultation of specialized doctors. If patients have the above conditions, they should go to the hospital as soon as possible and follow the doctor’s advice after completing the relevant examinations. Pay attention to rest after the operation to avoid complications.