- About 90 percent of stones pass
through the urinary system without treatment. In cases where this
does not occur, treatment to remove stones may be needed. Some stones
may be dissolved by medicines. In other cases, one of the following
methods of stone removal may be needed:
YAG Laser Lithotripsy
YAG pulsed solid state laser operating at the infrared wavelengths
has been approved for laser lithotripsy of urinary calculi. Because
of the difference in wavelength and pulse duration, the stone is
primarily drilled and not fractured. Unlike the pulsed dye laser,
fragmentation is achieved by drilling a number of holes in the stone,
which ultimately results in stone fragmentation. Additionally, the
YAG's laser pulse is readily absorbed in the ureter wall.
Extracorporeal Shockwave
Lithotripsy
Extracorporeal shockwave lithotripsy (ESWL) is the most frequently
used procedure for the treatment of kidney stones. In ESWL, shock
waves that are created outside the body travel through the skin and
body tissues until they hit the denser stones. The stones break down
into sand-like particles and are easily passed through the urinary
tract in the urine.
There are several types of ESWL devices. In one device, the patient
reclines in a water bath while the shock waves are transmitted. Other
devices have a soft cushion on which the patient lies. Most devices
use either x rays or ultrasound to help the surgeon pinpoint the
stone during treatment. For most types of ESWL procedures, anesthesia
is needed.
In most cases, ESWL may be done on an outpatient basis. Recovery time
is short, and most people can resume normal activities in a few days.
Complications may occur with ESWL. Most patients have blood in
their urine for a few days after treatment. Bruising and minor
discomfort in the back or abdomen from the shock waves are also
common. To reduce the risk of complications, doctors usually tell
patients to avoid taking aspirin and other drugs that affect blood
clotting for several weeks before treatment.
- Another complication may occur if
the shattered stone particles cause discomfort as they pass through
the urinary tract. In some cases, the doctor will insert a small tube
called a stent through the bladder into the ureter to help the
fragments pass. Sometimes the stone is not completely shattered with
one treatment, and additional treatments may be needed. ESWL is not
ideal for very large stones.
- Other therapies
- Percutaneous Stone
Removal
When stones are quite large (more than 2 cm) or in a location that
does not allow effective lithotripsy, a technique called percutaneous
stone removal may be used. In this method, the surgeon makes a small
incision in the back and creates a tunnel directly into the kidney. A
tube is inserted and the stone is removed through this tube.
Ureteroscopic Stone Removal
For stones found in the lower part of the urinary tract, the surgen
may pass a ureteroscope (a hollow tube-like device) up into the
bladder and ureter. A basket-like device may be passed through the
tube to grasp and withdraw the stone.
