The extracorporeal shock wave lithotripsy is used for the treatment of urinary stones. This technique does not involve any invasive methods and the patient only has to lie down on the machine resting on the left side on a cushion filled with water. The shock waves generated by the lithotripter pass through the human body, conveying all the energy on the stones, shattering them. The duration of treatment is rather short (generally no more than 45-60 minutes).
This therapy involves no anaesthesia; the patient may sometimes feel a sensation of temporary discomfort at the application point of the shock waves. In the event of a successful treatment, varying from 30 to 90% depending on the characteristics of the calculation, the fragments will be eliminated in the urine in the following days, sometimes with colic. The first urine passed after treatment is generally bloody but with each passing hour and fluid intake, it will normalize. When the stone is large (greater than 2 cm) there is no longer an indication for treatment with shock waves, because the mass of the fragments produced could obstruct the ureter, causing urinary obstruction. In these cases it is necessary to proceed by endoscopic removal of the fragments, with the use of a ureteral catheter and temporary extension (Double J stent). Although it is the least invasive method available, it should not be considered harmless and therefore repeated over and over again in case of failure. It must be emphasized that, even though in very low percentages, the energy released during the treatment may result in short term hematomas of the kidney and, in the long term, arterial hypertension and diabetes mellitus.