Percutaneous nephrolithotomy (PCNL) is a preferred treatment for large stones within the kidney or upper ureter. The procedure involves making a small incision (1 cm) in the back overlying the location of the kidney. A tunnel is then created from the skin into the kidney to allow passage of a telescope. The telescope is used to locate the existing stone and any small stones that may not have been visible by X-ray. The telescope has an inner channel that allows passage of instruments that are used to break up the stone.
