People who have suffered from kidney stones rarely forget the experience. “About 12% of Americans experience kidney stones,” says Allen Seftel, MD, FACS. “And, once you’ve had one, you are 50% more likely to have another within 10 years.” A treatment offered for some patients with kidney stones is called Extracorporeal Shock Wave Lithotripsy (ESWL). Shock waves sound intense, so we asked Dr. Seftel what patients should know about it. “[ESWL] has been around for many, many years. It's very safe a