UW Health clinical trial examines new way of eliminating kidney stones

MADISON, Wis. – Kidney stones have been a painful reality for Ed Feiteira, who lives in Stoughton.

When the stones would form, it would feel like back pain, but then eventually move down below his waist. He would usually pass the stones in his urine, but once a larger stone caused pain so severe, he had to go the emergency room, he said.

“When you have a pain deep inside and you don't know what it is, it’s scary and it doubles you over,” Feiteira said.

Kidney stones form when calcium and other chemicals in urine become too concentrated and crystalize. They can block the flow of urine and become very painful. If stones become lodged in the urinary tract or kidney, surgery can be required to remove them.

In late 2023, a twist of fate led to the discovery of a large kidney stone that wouldn’t pass on its own. Feiteira, who works as a mechanic on exotic sports cars and rare automobiles at Autohandler in Fitchburg, was having significant pain from an issue with his upper leg.

During an X-ray on his hip, his care team noticed a 2-centimeter kidney stone had formed. It was too big to pass through his urinary tract, so it was sitting in his kidney and would require surgery.

“It didn’t cause any pain,” he said. “I had no idea it was there.”

Traditionally, urologists eliminate large stones by making an incision in the back, entering the urinary tract and pulverizing the stones before sucking them out — somewhat like how a dentist might remove excess water and toothpaste during a dental visit. The procedure requires a team of people to operate the equipment to break up the stone and clear out the resulting particles.

Through his urologist, Dr. Margaret Knoedler, endourologist, UW Health, and assistant professor of urology, University of Wisconsin School of Medicine and Public Health, Feiteira was given another option — a clinical trial using flexible robotic technology called the MONARCH Platform for Urology, a Johnson & Johnson MedTech product.

UW Health is one of the first sites in the country to use the new technology, which is essentially the same procedure historically used to remove large stones but guided by a robotically assisted device controlled by the urologist. The urologist holds the device controller and guides the scope and catheter on a screen, while the robotic platform helps the urologist navigate the procedure by allowing for more precise movements as well as potential for less radiation exposure and fewer needle sticks.

Following an initial study at the University of California-Irvine, a 60-person, post-market clinical trial was launched in January with the UW School of Medicine and Public Health as the first of three sites for the larger trial.

Knoedler and her research team are participating in the trial of the MONARCH Platform for Urology to see if it can break up the stones more thoroughly and remove more of the stones and the resulting dust than the traditional non-robotically assisted technique.

The findings of this study will also support additional research and development efforts. The trial is open to people 22 years old and older who have a kidney stone equal to or greater than 1 centimeter and who are eligible for traditional percutaneous nephrolithotomy.

“Our goal is to find a better way for patients to be stone-free and remain that way,” Knoedler said. “We want to know, will the patient have any stones left after this procedure?”

To determine this, patients come back to meet with Knoedler’s team 30 days after the procedure to discover if any stones are present. Patients are also monitored for 90 days for any other adverse reactions to the procedure.

Feiteira is now about two months removed from his procedure and is clinically free of stones, and while he is happy with the result, there was more to being part of the trial, he said.

Growing up, Feiteira witnessed firsthand how challenging the recovery process was for traditional kidney stone treatment. His dad also had kidney stones and they would cause him severe pain, Feiteira said. He recalled the massive scar on his dad’s abdomen and the long hospital stay and recovery he went through to get the kidney stones removed.

Now, thanks to the clinical trial, Feiteira was home from the hospital the day after his surgery and has a very small scar on his back. So, being part of a clinical trial to potentially advance kidney stone treatment even further was an easy decision, he said.

“It's all part of trying something new. Does it work better? Because, if it does, it will be easier for other people,” he said. “Anything that makes it quicker and easier is a good thing.”