1.The ureteral stent tube is named double J tube because the two ends of the tube are curled like the English word “J”, and it is also called pig tail tube because each end is shaped like a pig tail. Because of its support and internal drainage, it can relieve the temporary obstruction caused by ureteral inflammatory edema and prevent postoperative wound leakage and ureteral stricture. 2. Precautions: (1) Drink more boiled water, more than 2000 ML per day. (2) During the catheterization period, fix the catheter properly to avoid distortion, pressure and tube clamping, and keep the drainage unobstructed. (3) Avoid doing limb stretching and sudden squatting exercises, and avoid strenuous exercise and physical labor for four weeks after surgery to prevent the double J tube from slipping and moving up and down. (4) Reduce any factors that cause increased abdominal pressure, such as preventing constipation and keeping the bowels open; avoid violent coughing and do not hold urine to reduce bladder urine reflux. (5) Take the double J tube under cystoscopy about 1 month after surgery, or it can be adjusted according to appropriate, up to 3 months. 3.The uncomfortable symptoms that may be caused by the placement of the ureteral double J tube in vivo are as follows: (1) Bladder irritation syndrome: urinary frequency, urinary urgency, and hematuria. (2) Back pain when urinating. (3) Pain in the abdomen after urination. (4) If severe hematuria, lumbar pain, fever over 38.5 degrees or urinary incontinence occurs after placement of the ureteral double J tube, it is recommended to seek immediate medical attention.