1. Ureteroscopy is a minimally invasive procedure that uses the natural lumen of the human body. Under semi-body anesthesia, a ureteroscope (slightly thicker than a ball-point pencil) goes in through the urethra, to the bladder, and then inside the ureter for lithotripsy, with specific lithotripsy equipment such as holmium laser, pneumatic ballistics and ultrasound (through the working channel inside the ureteroscope). There is no incision in this procedure. 2. After the operation, due to anesthesia, a catheter (usually removed one day after the operation) and a ureteral catheter (commonly known as “pig tail tube”) will be left in the body for about 4 weeks to drain urine, avoid blocking the ureter with blood clots or small stones, and reduce mucosal edema in the ureter. At that time, the cystoscope is removed under local anesthesia. 3. The risks of surgery may include urinary sensation, hematuria, ureteral injury, ureteral perforation, upward migration of stones into the kidney and the need for further treatment by extracorporeal shock wave lithotripsy, etc. The degree of hematuria after surgery is usually mild.