Small kidney stones may drop into the ureter (the tube that drains urine from the kidney to the bladder) and cause pain and blockage of the urine flow from the kidney. A surgical procedure called ureteroscopy can be used to treat stones in the ureter. In this operation a small endoscopic instrument is passed through the urethra (the tube from the bladder to the outside of the body) through the bladder and up the ureter into the kidney. Devices can be inserted through the instrument to break up stones in the kidney or the ureter (such as the laser), take samples of tissue to rule out cancer and to electrocauterize, or burn, areas of bleeding in the kidney or to cut scar tissue blocking the ureter. After ureteroscopy a stent (a small tube that passes from the kidney, down the ureter to the bladder) is typically left inside the body for several days to weeks. This stent helps to keep the kidney drained, but also causes blood in the urine and some discomfort in the bladder and back. Once the stent is removed, these symptoms will disappear in 1-2 days. The ureteroscopy procedure can usually be performed as an outpatient or an overnight stay in the hospital. There is much less discomfort with ureteroscopy compared to an open flank incision and the patient can get back to regular activities within a few days or a week of the procedure.