Roughly one out of every ten people in the U.S. will develop a kidney stone at some point in their life.  Kidney stones are hard mineral deposits that form in the kidney and are eventually released through the urethra.  The process of eliminating a kidney stone can be very painful for the person experiencing it and sometimes surgery is needed.  One procedure used to treat kidney stones is electrohydraulic lithotripsy (EHL)—a process in which a physician uses a flexible probe to break-up the small stones with shock waves generated by electricity. Using a ureteroscope, the probe is positioned close to the stone; once the stone is broken up, fragments can then either be passed by the patient or removed by the physician.  An EHL does require general anesthesia and can be used to break stones anywhere in the urinary system.