Lithotripsy is the technology that allows us to break up stones in the urinary tract (such as kidney, Ureter and Urinary Bladder stones) using shockwaves.
Shock waves may be generated at the tip of an instrument placed directly on a stone (intracorporeal lithotripsy), or may be generated by an electrohydraulic or electromagnetic source outside the body and transmitted to the stone (Extracorporeal Shock Wave Lithotripsy, or ESWL).
Nowadays, with lithotripsy, the stones are simply crushed into sand-like particles which pass out, harmlessly, in urine. Usually, patients are hospitalized for a day or two and in some cases, lithotripsy may be done on an outpatient basis.
How it works
A shock wave is characterized by a very rapid pressure increase in the transmission medium and is quite different from Ultrasound. The shock waves are transmitted through the patient's skin and pass harmlessly through the patient's soft tissue. The shock wave passes through the kidney and strikes the stone. At the stone boundary, energy is lost, and this causes small cracks to form on the edge of the stone. The same effect occurs when the shock wave exits the stone. With successive shocks, the cracks open up, and in turn, smaller cracks form within the large cracks. Eventually, the stone is reduced to small particles, which are then flushed out of the kidneys or ureter naturally during urination.
The process generally takes about 45 mins to one hour during which 1000 to 2000 shocks or sometimes up to 8000 shocks are administered. The patient will experience some discomfort during the treatment depending on the patient's pain tolerance. Analgesics may be administered to make the patient more comfortable.
Pro's and con's
The main advantage of this treatment is that many patients may be treated for kidney stones without surgery. As a result, complications, hospital stays, costs and recovery time are reduced. Unfortunately, not all types of kidney stones can be treated this way. In addition, stone fragments are occasionally left in the body and additional treatments are needed.
Most patients have some blood in the urine for a few days. The shattered stone fragments may cause discomfort as they pass through the urinary tract. Sometimes, the stone is not completely shattered, and additional treatments may be needed.