ESWL defined

"Extracorporeal shock wave lithotripsy (ESWL) uses highly focused impulses projected from outside the body to pulverize kidney stones anywhere in the urinary system. The stone usually is reduced to sand-like granules that can be passed in the patient's urine. Large stones may require several ESWL treatments. The procedure should not be used for struvite stones, stones over 1 inch in diameter, or in pregnant women."