Because percutaneous nephrolithotomy is done using general anesthesia, the patient will need to be assessed for any risks associated with the procedure. Once you pass the assessment you will receive anesthesia that will put you to sleep. The doctor will use a fluoroscope to determine the site for the insertion of the scope and make a small incision, about one centimeter in length, in your back. This allows the doctor to insert the nephroscope into the kidney. When the doctor finds the stone, they will break it up into smaller pieces using a small tool called a lithoclast lithotripsy before removing them through the incision. The doctor may also turn the stones into sand-like particles and remove it using ultrasonic lithotripsy.