After kidney stone surgery, a ureteral stent tube will be left in the body, which is a necessary step after the surgery. The ureteral stent tube is mainly used for two purposes: firstly, to support the kidney, after the lithotripsy, many small stone particles may remain in the kidney. If this ureteral stent tube is not placed, the tiny stone particles may be discharged into the ureter in an instant, causing acute blockage of the ureter, and the patient may have acute back pain or signs of hydronephrosis, perinephric infection, or pelvic infection after the surgery, requiring a second surgery to unblock the ureter. After the ureteral stent tube is placed, it can effectively avoid acute ureteral obstruction and play the role of supporting the ureter and avoiding obstruction. Secondly, it plays the role of drainage. After the surgery, there may be local edema of the wound. After edema, it can lead to narrowing of the ureteral lumen, resulting in poor drainage of urine and symptoms of infection or back pain. Placing a ureteral stent tube plays the role of drainage, so that the patient can pass the infection or edema period and wait for good healing before pulling out, which will not lead to acute infection and edema, resulting in hydronephrosis or acute pain.