Surgical Treatment Options

Once a decision has been made that a stone requires a procedure, the next step is to decide which operation is most suitable. This will depend on many factors including the location of the stone, its size, stone composition, the presence of symptoms and patient preferences.

Extracorporeal Shockwave Lithotripsy (ESWL)

This treatment is frequently used for the treatment of kidney stones which are less than 2cm in size. It is less frequently used for stones in the upper ureter (just below the kidney). Extracorporeal Shockwave Lithotripsy, usually referred to as ESWL, is not usually used for stones in the mid and lower ureter or for stones causing pain and obstruction.

ESWL is a procedure which breaks kidney stones by focusing sound waves onto the stone. These sound waves are audible and are not ultrasound (which cannot be heard). The sound waves pass from the ESWL machine through the skin and muscles, through the outside of the kidney onto the stone. The energy from the focused sound waves is very high – enough to break many stones.

The procedure is performed in a Melbourne hospital under a general anaesthetic, usually as a day case. The stone position is identified using an ultrasound machine which is attached to the ESWL machine. The stone is then treated with individual “shock waves” each taking about half to one second. A total of 2000 – 3000 shocks are generally used to fragment a stone and this takes 30 – 45 minutes.

What to expect after ESWL

After ESWL, stone fragments need to pass naturally out of the kidney, down the ureter and through the urethra (water-pipe). Usually this passage of fragments does not cause pain as the pieces are small and do not cause any blockage while passing down the ureter.

Following ESWL many patients will see some blood in the urine for a few days and many will notice bruising in the loin with usually only mild discomfort.

It is not generally possible to tell how well the stone has broken up immediately after ESWL and patients require further imaging (often with an ultrasound) to determine whether the calculus has fragmented and all the pieces have passed out

Considerations of ESWL

EWSL is extremely safe. Despite the energy being sufficient to break many stones, the kidneys are very rarely harmed at all. The risk of damaging other structures or organs with ESWL is extremely low.

One of the advantages of ESWL is that patients usually do not require a ureteric stent post treatment. Stents can be irritating and many patients find them uncomfortable. See Ureteric Stent

The biggest disadvantage of ESWL is that some 25% of stones do not break at all or break into large pieces which do not pass out. Occasionally following ESWL a fragment tries to pass down the ureter but gets stuck resulting in obstruction and severe pain called renal colic. This may well require hospitalization and sometimes a procedure to retrieve the fragment with a telescope (ureteroscopy).

If ESWL is only partially successful at eradicating a kidney stone, it may be possible to treat the stone again with ESWL. If a stone is found to be completely resistant to fragmentation with ESWL, other treatment options such as ureteropyeloscopy need to be considered.

Ureteroscopy / Pyeloscopy / Ureteropyeloscopy

This is a procedure that involves inserting a fine telescope through the urethra (water-pipe) into the bladder and then up the ureter into the kidney. When the telescope is inserted only up to the ureter (eg for a stone in the ureter) it is called ureteroscopy. When the procedure involves inserting the telescope all the way up to the kidney, it is called renal pyeloscopy. Ureteropyeloscopy is a general term used to describe either of these operations.

The procedure can be performed using a straight instrument called a rigid ureteroscope, and this is done when access is only needed to the ureter. When access is needed into the kidney, a flexible instrument (flexible ureteroscope or flexible ureterorenoscope) is usually utilised.

Ureteropyeloscopy is performed under a general anaesthetic, usually as a day case or an overnight stay in hospital. A ureteroscope is inserted into the ureter or kidney without the need for an incision. The stone is visualized directly and fragmented into small pieces using a Holmium Laser through a channel in the instrument. This type of laser will break up any stone – there is no stone which is too hard to fragment. The pieces of stone are then grasped with a basket and extracted out of the body, with only very fine pieces or powder left behind – these tiny fragments can easily pass naturally. The procedure usually takes 45 – 120 minutes with longer times required for larger stones.

The Ureteric Stent

Following stone extraction, a stent is usually left in the kidney. This is a hollow, fine soft tube which is placed between the kidney and bladder through the inside of the ureter. The stent allows free passage of urine from the kidney to the bladder without obstruction. A stent is needed after ureteropyeloscopy as the procedure results in bruising and swelling of the ureter that will cause ureter blockage if a stent is not placed.

The stent is usually removed after a few days to a few weeks depending on the particular circumstances. Ureteric stents cannot stay in the body indefinitely (unlike heart/coronary stents) as they will cause further stone formation leading to stent blockage. Removal of a stent is a minor and safe procedure which may be performed under local anaesthetic or with sedation as a day case in hospital. Stents not infrequently cause side effects – see Ureteric Stent.

Success Rate

There is little need for patients to be concerned about this procedure, particularly as Kidney Stone Melbourne Urologist Mr Uri Hanegbi is extremely experienced at treating kidney stones. Ureteropyeloscopy has a very high success rate at treating ureteric and renal stones, with much higher chances of success compared with Extracorporial Shockwave Lithotripsy (ESWL). Sometimes it is not possible to gain access to the stone with ureteropyeloscopy because the ureter is too narrow to fit the telescope (some people have very narrow ureters). In this circumstance, a stent is inserted into the kidney and the stone is not treated initially. The stent is much narrower than the telescope and it is nearly always possible to insert a stent even if the ureter is narrow. In this circumstance, the stent will gradually stretch the ureter over a period of a couple of weeks and at the time of stent removal, it is frequently much easier to insert the ureteroscope up to the stone in order to treat it.

In other words, ureteropyeloscopy nearly always requires two procedures. Usually, the first to treat the stone and the second to remove the stent; but at other times, to first insert a stent and then later to treat the stone at the time of stent removal. Patients with larger, more complex or difficult to access stones may even require a third procedure to achieve stone clearance.

Safety

Ureteropyeloscopy is a very safe procedure as no incision is performed and the body’s natural urinary channels are used to gain access to the stone. The risk of damaging the urinary system is very low. Ureter injury may occur if the ureter is tight or the stone very stuck in the ureter, but injuries to the ureter tend to heal themselves very well, without the need for surgical repair. Very rarely, a ureter may be damaged severely and this may require an open operation to repair the injury – this is extremely uncommon. Although the laser used to treat renal calculi is very powerful, it does not tend to damage the kidney as the laser only has a penetration of 0.4mm! Furthermore, the stone can be seen clearly and is fragmented under direct vision to make sure no other structures are damaged.

Side Effects

The side effects of ureteropyeloscopy tend to be mild. Loin pain is usually minor and many patients can therefore go home on the day of surgery. Visible blood in the urine is common and not a concern – this may continue until the stent is removed. Many patients will experience side effects from the presence of the ureteric stent. The risk of infection is low and the risk of damage to the urinary system is very low. Historically, there were reports of some patients developing a narrowing in their ureter following ureteroscopy due to formation of scar tissue – this is called a ureteric stricture. Now that surgical techniques and instruments have improved, this is a very rare complication.

Percutaneous Nephrolitholtomy (PCNL)

This procedure involves making a hole through the skin, through the muscles and through the outside portion of the kidney in order to gain access to the inside of the kidney where stones are located. The procedure is performed under a general anaesthetic and takes 1-3 hours. X rays are taken at the time of the operation to guide access into the kidney. A telescope is used to inspect the inside of the kidney to find the stone or stones and under direct vision the stones are fragmented and the pieces removed.

A nephrostomy tube is left in the kidney through the puncture in the skin to facilitate drainage of blood, urine and stone fragments for a day or two. Patients are generally hospitalized for 2-4 days.

PCNL is generally used for larger kidney stones (greater than 20 mm) and most staghorn calculi. It was previously used for 10-20 mm kidney stones but this is becoming rarer as these type of calculi are more often treated now using ureteropyeloscopy.

The advantage of PCNL is that it has a high likelihood of eradication even extensive kidney stone disease with a single operation.

The disadvantage of PCNL is that because a hole is needed through the kidney, there is a risk of bleeding which is sometimes very serious. Bleeding may require further a blood transfusion or intervention to control the blood loss and rarely results in a need to remove the entire kidney. There is also a small risk of damaging other structures around the kidney such as the spleen, liver, bowel, lung or large blood vessels. There is a risk of serious infection and patients may require intravenous antibiotics prior to or after a PCNL.

Open and Laparoscopic Renal Stone Surgery

Surgery for stones in the ureters or kidneys was frequently performed with a large incision in the skin some 40 years ago, before the invention of ureteroscopy and Extracorporeal Shockwave Lithotripsy (ESWL). Now open stone surgery is extremely rare as nearly all stones can be treated with less invasive techniques.

Very rarely, it is not possible to gain access to a stone with ureteroscopy or PCNL and the stone cannot be fragmented with ESWL. In this circumstance, surgery can be performed with either a large skin incision or a few smaller incisions using laparoscopy. This is necessary in less than 1 in 1000 cases.

Some patients who require laparoscopic kidney surgery to repair a blockage in the system between the kidney and ureter, can also have their kidney stones removed with the laparoscopic instruments.

Open and laparoscopic surgery are more invasive and are therefore associated with longer lengths of stay in hospital. There is a higher risk of all complications including bleeding, infection and wound hernia, and therefore, this type of operation would only be considered if all other options have been exhausted.