Kidney Stone Removal Methods and Techniques
Lithotripsy (stone crushing) is the kidney stone removal method where the stone is fragmented either by energy applied from outside the body (shock wave in ESWL) or from within in ureteroscopic methods (laser lithotripsy). These methods will only be considered if other forms of treatment like kidney stone medication has been ineffective or if the stone is causing an obstruction or severe kidney stone pain.
Extracorporeal Shockwave Lithotripsy (ESWL)
This is an outpatient procedure and overnight hospitalization is not necessary unless there are complications or other risk factors present. Extracorporeal (outside-body) means that no device will have to be inserted into the urinary tract, except if a ureteral stent is necessary.
- Local anesthesia and intravenous (IV) sedation is commonly used. General anesthesia (GA) may be administered in certain cases. Fasting for up to 8 hours before general anesthesia is recommended while a 4 hour fast may be sufficient for IV sedation.
- The patient lies down on a water filled cushion on the lithotripter table. With older machines, the patient may need to be partially submerged in water.
- The location of the stone is isolated by the use of an ultrasound or fluoroscopy. This also assists with tracking the movement of the stone(s) during the procedure.
- High energy shockwaves are generated outside the body by a machine known as a lithotripter and applied over the target area. These shockwaves will not damage other organs and tissue in the body.
- A ureteral stent, which is a thin plastic tube inserted through the urethra, into the bladder and up into the ureter, may be necessary to allow for the stones to pass out more easily.
- The entire procedure may last for up to an hour or even two although the lithotripsy part may only take 20 to 30 minutes.
This is also known as endoscopic or intracorporeal (inside-body) lithotripsy. This is an outpatient procedure as well but due to the use of general anesthesia, the presence of any risk factors or complications that may arise during or after the procedure, hospitalization may be necessary.
- This procedure is conducted under general anasthesia (GA).
- A thin flexible (sometimes rigid) tube-like viewing device, known as a ureteroscope, is passed up the urethra, into the bladder and up the into the ureter along with a guiding wire. This will allow the urologist to actually see the stone in the ureter.
- Small stones can be grasped with a wire prong grasper or basket. Larger stones will need to be fragmented and sometimes a special type of basket is inserted to prevent the stone from moving higher up the ureter.
- A laser fiber is inserted up the ureter which delivers the laser energy to the stone. The laser machine itself does not enter the body. Laser lithotripsy is preferred over other forms of intracorporeal lithotripsy like pneumatic mechanical or electrohydraulic devices.
- A ureteral stent is inserted for drainage.
- The procedure may last for approximately 90 minutes but can extend for up to 3 hours.
If none of these methods are effective or viable, percutaneous nephrolithotomy or open surgery may be considered.