How do we remove a stone from the kidney?

Until not so long ago, treating a kidney stone required major surgery. Today, with greater understanding and advanced technology, science has developed treatment alternatives and less invasive approaches for the majority of problems. The decision to prefer one treatment over another is influenced by the number of stones, their size, location and composition. And of course by the patient's physical state and medical history.

Extracorporeal Shock Wave Lithotripsy (ESWL - shattering the stones)
This is the most common form of treatment for kidney stones. The method involves directing shock waves at the stone. The waves are generated by an external shattering machine (lithotriptor) and hover outside the body, penetrating the skin and tissues until they reach the stone in the kidney or the ureter.

The treatment is administered together with an x-ray, so that the waves are directed to the stone's precise location. Repeated shock waves cause the stone to break into smaller pieces which can then leave the body in the urine. The first shock wave treatment was introduced in the 1980s and is still in widespread use today.

At Shaare Zedek, the procedure is performed under local anesthetic, in the afternoon, and requires overnight hospitalization.

After the treatment, it is normal for the patient to feel discomfort around the waist. Blood is also liable to appear in the urine for a few days. Painkillers are permitted. There is usually no need for antibiotics if the patient does not have a history of urinary infection. This treatment should not be performed in the following cases: during pregnancy, blood coagulation disorders, urine infection or an aneurysm in the aorta near the stone being treated.

The size and composition of the stone will affect the results of this kind of treatment. Stones composed of cystine or different types of relatively hard calcium stones will not react as well to this treatment. Bigger stones may not shatter as needed and the patient may need more treatment.

A possible consequence of ESWL is a partial or insufficient break, which still does not allow the stone to pass through the urine.

In most cases, after ESWL, the patient is discharged the next day and asked back for a check-up within 2-4 weeks. For this visit the patient will be asked to bring an x-ray of his or her empty stomach or a sonar of the kidneys and urinary tract to confirm that the stone is indeed no longer there.

Treatment using small telescopes inserted into the bladder and opening of the ureter. The telescope enables the doctor to look at the stones in the ureter or the kidney. Depending on the size of the stone and the diameter of the ureter, the stone will be shattered or removed. The accepted method for shattering kidney stones is via laser. The laser passes through a small channel in the telescope and shatters the stone into smaller pieces. One of the advantages of this treatment is its ability to directly observe the stone-shattering process. Apart from that, the pieces can be gathered and analyzed using a micro 'basket' to gather the shards through the telescope.

Holmium Laser
This is considered the safest and most efficient treatment suitable for all types of stone shatterers. We have one of these advanced lasers at Shaare Zedek. This laser has a number of advantages over other types of laser. It is able to transmit its energy through a flexible fiber, which means it can work in both the kidney and the ureter, and it breaks the stone down into smaller pieces, which is more efficient than other stone-shattering methods.

In many cases, passing the arthroscope through the small tube in the ureter can cause an edema (accumulation of fluids) in the area. This in turn can cause blockage and so doctors leave an internal stent (or double J) in the ureter after the surgery. The stent enables the urine to pass from the kidney to the bladder and temporarily bypasses the blockage. The stent is usually removed within 1-4 weeks after the operation. This is done in the Urology Institute under local anesthetic and only takes a few minutes. In many cases we tie a thin thread to the stent which will come out through the ureter and the patient is discharged. After a few days, the patient comes back and the doctor pulls the stent out using the thread. This also takes a few minutes and involves no significant pain. The stent can cause light bleeding in the urine and symptoms similar to urinary infections. This is because the edge of the stent sits in the bladder, a foreign body stimulating the bladder.

This is considered a very safe procedure but like any procedure, complications can arise. Sometimes scarred tissue in the ureter can cause stenosis and disturb the passage of urine from the kidney. This occurs mainly in cases when the stone is affixed in the tissue or the ureter is punctured during the surgery. However, thanks to technological developments, these complications occur in less than 1% of patients.

Percutaneous Nephrolithotomy(PCNL) (removal of kidney stones through the skin)
This is the optimal; treatment for large stones in the kidney or upper ureter. The surgery is usually performed under general anesthetic and involves a cut of about a centimeter in the waist above the kidney, through which the surgeon passes a telescope straight into the kidney. The telescope allows the surgeon to identify the stones in the kidney. The telescope is also the conduit for other devices which are used to shatter the stones and suck up the shards. In most cases, no stones remain at the end of the operation and so there is no need to pass the shards through the ureter to the bladder.

A small tube (nephrostum) is left in the waist area after the surgery. This drains urine out of the kidney and allows it to recover. An x-ray is taken to confirm that no trace of the stones remain and that there is no blockage in the passage of urine between the kidney and the bladder. In a minority of cases some stone 'crumbs' may still lie in the kidney and another, much shorter, procedure may be needed, under sedation or anesthetic. After a few days and after the x-rays, the tube is taken out. Usual hospitalization time is two nights.

Although PCNL is a safe procedure, complications can occur. There is a certain amount of bleeding when expanding the passage from the waist to the kidney but serious bleeding is very rare (1-2% of cases.) A high temperature is common and may be a sign of infection in the urinary tract. Antibiotics can usually bring the temperature down to normal.

This treatment is used in rare cases. Sometimes the kidney stone is formed due to a congenital blockage in the kidney exit and surgeons can often correct the stenosis laparoscopically, at the same time removing the stone from the kidney.