Lithotripsy
Lithotripsy is a medical procedure used to treat kidney stones by fragmenting them into smaller pieces that can be easily passed through the urinary tract. This less invasive technique is generally preferred over traditional open surgery, as it involves minimal blood loss, reduced pain, and quicker recovery times. There are two primary methods of lithotripsy: extracorporeal shock wave lithotripsy (ESWL) and percutaneous lithotripsy. In ESWL, shock waves are generated outside the body and directed at the stones, while percutaneous lithotripsy involves inserting a nephroscope through the skin to directly break up the stones using ultrasonic waves.
Patients typically receive local or general anesthesia during the procedure. While lithotripsy is considered safe with a low morbidity rate, potential complications can include bleeding, urinary tract perforation, and temporary hematuria (blood in urine). Although serious side effects are rare, ongoing research is examining possible associations between ESWL and hypertension in certain patients. Overall, lithotripsy is recognized for its efficacy and is a common choice for treating kidney stones, allowing for a swift return to normal activities with minimal disruption.
Subject Terms
Lithotripsy
Anatomy or system affected: Abdomen, bladder, kidneys, urinary system
Definition: A method of breaking up stones in the kidneys, ureters, and urinary bladder using shock waves or high-frequency sound waves.
Indications and Procedures
Stone fragmentation using shock waves or ultrasonic waves is less invasive, less painful, and less time consuming than conventional open surgery to remove stones or the organs that contain them. With lithotripsy, blood loss is minimal and recovery is quick, with a low morbidity (injury rate).
In extracorporeal shock wave lithotripsy (ESWL), the patient is given either local or general anesthesia. A machine called a lithotripter is placed on the abdomen over the site of the stones. An emitter in the lithotripter sends out shock waves that break the stones into fine fragments that can pass through the urinary tract without harm to the patient, who is encouraged to drink copious amounts of fluid following the procedure.
In ultrasonic lithotripsy, an incision is made in the skin. The stone is approached and visualized with an endoscope, a hollow instrument with a telescope at one end for visualization. The other end of the instrument is introduced via the urethra into the bladder or ureter or via a small skin hole into the kidney. For kidney stones, a small needle is introduced into the kidney through the back under X-ray control, and a nephrostomy tract is established between the skin and the kidney. The ultrasonographic lithotripsy probe is introduced through the endoscope and brought in contact with the stone.
A piezoceramic crystal is electrically stimulated, which generates ultrasonic waves that will fragment the stone. The design of the probe allows it to suction out the broken stone particles simultaneously. Larger stones can be fragmented into smaller pieces, which can then be grasped with forceps and pulled out. When a ureteral stone is treated by this method, a plastic tube (a double-J stent) is left in the ureter to prevent postoperative blockage and future scar formation. When a kidney stone is treated by this method, a large-caliber tube is left in the kidney (a nephrostomy tube) to drain the kidney and secure a tract for future X-ray studies and reinspection of the kidney for possible residual stone fragments.
Uses and Complications
The main morbidity associated with this procedure occurs during the establishment of the nephrostomy tract to gain access to the kidney, which can lead to bleeding, or during the introduction of the endoscope into the ureter, which can lead to perforation and future scarring. During stone fragmentation, it is imperative that the probe be in direct contact with the stone at all times, or it may cause ureteral perforation and bleeding. Overall, however, ultrasonographic lithotripsy is a safe and effective method of stone treatment, with few injuries and a quick recovery.
As with ultrasonic lithotripsy, few serious complications are associated with shock wave lithotripsy. The presence of blood in the urine, hematuria, may be noted but is usually only temporary, as the stone fragments pass through the ureters, bladder, and urethra. Abdominal bruising may also occur, but this complication is minor in comparison to more invasive techniques. Severe pain that is unresponsive to medication may rarely signal perirenal hematoma. Other rare complications include pancreatitis and nerve palsy. Research was ongoing as of the early 2020s regarding the possibility of an association of ESWL with the development of hypertension in some patients. To avoid any risk, some patients may be advised to undergo ureterorenoscopic lithotripsy rather than shock wave lithotripsy.
Bibliography
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