Indications: Ureteral obstruction for some reason (e.g. injury or tuberculosis, etc.) and systemic condition does not allow other methods to release the obstruction. Those with pus accumulation in the kidney, whose systemic condition does not allow nephrectomy, or those who have other reasons to preserve the diseased kidney. Advanced bladder cancer that blocks the ureters on both sides. After kidney stone extraction. Postoperative care When the fistula leads to more urine sediment, renal pelvic urine culture, bacterial count and drug sensitivity test should be performed. Sodium bicarbonate or ammonium chloride 1.0g each, 3 times a day; or methylene blue 100mg, 3 times a day should also be given according to urine pH to prevent the formation of stones by deposition. 1, after the operation, the catheter will be connected to the sterilized rubber tube and guide bag, the patient should always take the supine position to facilitate drainage, and pay attention to keep the drainage tube unobstructed and not fall off. If the catheter is blocked by blood clot, pus clot and necrotic tissue, use 1:5000 chlorhexidine solution or 1% neomycin solution to rinse, in order to be smooth. 2.The catheter may be blocked after being left for a long time and should be replaced. The first time in the postoperative 3 to 4 weeks to replace, after every 2 to 3 weeks to replace. When replacing the catheter, it is important to emphasize that another sterilized muscarinic catheter or general catheter of the same diameter should be prepared in advance and inserted into the new tube immediately after the original catheter is removed. If the catheter is not prepared in advance and delayed, it may not be easily inserted due to changes in the fistula pathway when it is inserted again. (1) Pelvic ureterogram to observe whether there is obstruction of the renal pelvis and ureter, and after completion of the imaging, rinse with saline and inject 1% neomycin solution, keep the clamped tube for half an hour, and open the catheter after returning to the ward. (2) The temporary nephrostomy tube needs to be clamped for 24 to 48 hours before it is removed. During the clamped period, the tube can be removed if there is no lumbar distension, lumbar acidity, fever and increased bladder urine output, and if there is not much residual urine in the renal pelvis after the catheter is opened. The fistula will heal on its own within 1 to 2 days.