New Kidney Stone Treatment Clears Fragments In One Go

In a North American first, an exciting evolution in the treatment for kidney stones has debuted at St. Joseph’s Health Care London (St. Joseph’s) that offers the possibility of completely clearing stone fragments in a single procedure and significantly decreasing the risk of recurrence.

Using a flexible ureteral access tube (sheath) as part of standard ureteroscopy and laser lithotripsy, stone fragments broken up by the laser are suctioned out of the kidney during the procedure. This eliminates the need for patients to pass the fragments on their own in the days and weeks after treatment, which can be painful and may not result in all fragments passing, leading to a recurrence of stones.

Until now, this flexible ureteral access sheath, made by Vathin Medical, has only been used in China.

“The ureteral access sheath is a unique material and lined with overlapping scales that make it very flexible, allowing us to access difficult-to-reach caves and pockets of the kidney, even in patients with complex kidney anatomy,” explains St. Joseph’s urologist Dr. John Denstedt, a renown surgical innovator in the treatment of kidney stones. “Together with enhanced suction, the sheath dramatically increases the likelihood of patients being completely free of stones without having to pass the fragments after treatment.”

About 12 per cent of men and 10 per cent of women experience kidney stones, clusters of crystals that form from minerals and other substances in the kidneys that can result in severe pain. Due to diet and lifestyle, research shows the prevalence of kidney stones is on the rise.

Standard treatment for kidney stones involves inserting a ureteroscope – a long, narrow telescope-type device - through the urethra (the tube that drains urine) and bladder into the kidney.  Using this ureteroscope, the surgeon can see, inspect and treat problems of the ureter and kidney, such as kidney stones. For larger kidney stones, ureteroscopy is commonly used with laser lithotripsy in which a laser is used to break up the stones from inside the body.

When stones are more than two centimetres in size – a toonie or bigger - the kidney is accessed through an incision in the patient’s back.

“The new ureteral access sheath may allow the removal of stones up to three centimetres or larger using the less invasive ureteroscopy and laser procedure in a single treatment, says Denstedt. “This is a remarkable advancement and a great example of surgical innovation supported by St. Joseph’s.”

About 600 patients undergo ureteroscopy and laser lithotripsy at St. Joseph’s each year and Denstedt expects many of those individuals to be eligible for the new procedure as part of a clinical trial.

“Kidney stones are the most common issue that urologists look after and ureteroscopy is the most common procedure urologists use,” says Denstedt. “When you can break new ground like this with tremendous potential to improve outcomes, it’s very exciting for the surgical team, the organization and for patients everywhere.”

Bringing the Vathin flexible ureteral access sheath to North America is the latest of many firsts over several decades by the Urology Centre at St. Joseph’s in treating kidney stones.

In 1990, St. Joseph's became the second hospital in Ontario to offer shock wave lithotripsy, a non-invasive way to break up kidney stones from outside the body that combines X-ray to target the stone and a lithotripsy machine to break it up.  The service quickly became the busiest in the world before ureteroscopy became the standard of care. St. Joseph’s continues to house one of only two lithotripsy machines in the province, which is used to treat about 500 patients a year with kidney stones. Shock wave lithotripsy is most suitable for smaller stones in the kidney visible on X-ray.

In 1993, St. Joseph's urologists were the first to treat a human for kidney stones using a holmium laser, a treatment now used around the world.

Since that time, Denstedt and his colleagues have continued to make waves - literally and figuratively - in the care of patients with kidney stones.