A third type of procedure, called Uretero Reno Scopy (URS), allows treatment of stones in the mid and lower parts of the ureter. A thin endoscope, called an Uretero Reno Scope is inserted through the urethra (without an incision) into the bladder and ureter. The stone can then be removed via a cage-like instrument (stone basket) or shattered with an ultrasonic probe or laser. This procedure also allows for the option of pushing the stone back into the kidney from where ESWL can be performed better. A stent may be left in the ureter for a few days until the reaction to the instrumentation subsides.