Lithotripsy ( litho = stone, tripsy = to crush) is sometimes referred to as Extracorporeal (outside the body) Shock Wave Lithotripsy (ESWL). This non-invasive technology using a machine called a lithotripter safely and effectively disintegrates the stone into small particles with shock waves aimed directly at the stone. Shock waves are energy pressure waves. These shock waves pass safely through the body. Devices mechanically focus the shock waves greatest energy on the kidney stone. This impact of repeated shock waves causes the stone to crack and crumble into tiny pieces without causing damage to the surrounding tissue. Breaking down the kidney stone into smaller particles allows the body to expel the stone naturally.
The patient lies on top of a soft cushion through which the waves pass. The body is positioned so that the stones can be targeted. Thousands of shock waves may be needed to crush the kidney stones. Your urologist will evaluate the stone’s fragmentation during the procedure. Each treatment takes approximately 60-90 minutes.
Post SWL, most patients have small amounts of blood in the urine for a few days and the tiny fragments may cause discomfort as they pass. If a stone is not completely shattered, additional treatments may be needed. Not all stones are amenable to treatment with SWL and the size, location and composition of the stones must be taken into account when exploring treatment modalities. Also, the stones must be clearly viewed by x-ray or ultrasound so the shock waves can be targeted accurately. If anatomical abnormalities prevent proper targeting of the kidney stone(s) then other treatment methods will be considered.
In those patients thought to be good candidates, 70 to 90 percent are found to be free of stones within three months of treatment. The highest success rates seem to be in people with mobile stones that are located in the kidney and upper ureter. Occasionally, some patients may still have stone fragments that are too large to be passed after treatment. If symptoms persist, these can be treated with lithotripsy again.