BEST KIDNEY STONES TREATMENT : Do You Really Need It?

 A noninvasive ultrasound technique is capable of quickly pulverizing kidney stones, an early study shows—in what researchers call the first step toward a simpler, anesthesia-free treatment for the painful problem.

The study reports on the first 19 patients who've had kidney stones treated with the ultrasound "bursts

So far, it's been able to complete, or nearly completely, break up stones within 10 minutes.

Much more research lies ahead, but experts not involved in the study called the early results "exciting.

If it pans out, they said, the ultrasound technique could make noninvasive treatment for kidney stones more readily available to patients.

Kidney stones are common, affecting about 10% of people at some point, according to the National Kidney Foundation.

Often, a stone can be passed in the urine without too much agony. 

In other cases—such as when a larger stone is causing a blockage or unbearable pain—treatment is necessary.

Right now, many kidney stones can be treated with a procedure called shock wave lithotripsy. 

It delivers high-energy sound waves through the skin to break the stone into tiny fragments that can then be passed.

But there are downsides, said Dr. Mathew Sorenson, of the University of Washington School of Medicine in Seattle, one of the researchers on the new work.

Shock wave therapy can be painful, so it's typically done in the operating room, with patients under anesthesia, in the United States.

Sorenson and his colleagues have been developing an alternative approach called burst wave lithotripsy. 

They say it has the potential to blast kidney stones in a shorter amount of time, and possibly without anesthesia.

The ultimate goal, the researchers said, is to perform the procedure on fully awake patients, 

during an office visit with a urologist—or even in the emergency room when patients arrive in severe pain.

Unlike shock wave therapy, the burst wave approach uses "short harmonic bursts" of ultrasound energy, according to the research team. Previous research has suggested it can break up stones more quickly, and with less pain, than shock waves.

In the new study, the researchers tested the burst wave technique in 19 patients who were undergoing kidney stone treatment with a procedure called ureteroscopy. It involves threading a thin scope through the urethra, up to the location of the kidney stone; instruments are used to either snare the stone or break it into fragments that can be removed.

Because ureteroscopy requires anesthesia, the study patients were under when the ultrasound bursts were applied, for up to 10 minutes.

Overall, the researchers found, that was enough to fragment 21 of 23 stones. Half of the stones had at least 90% of their volume pulverized to pieces of no more than 2 millimeters (mm). And nine stones (39%) were completely broken down to that degree.

The findings were published recently in The Journal of Urology.

Two urologists who were not involved in the study called that effectiveness impressive, considering the short duration of treatment (which was chosen to limit patients' time under anesthesia).

Kidney stones broken down to 2 mm or less should be relatively easy to pass, said Dr. Mantu Gupta, director of the Kidney Stone Center at Mount Sinai, in New York City.

Gupta noted that the study did not test the hoped-for, real-world scenario: Using the technique without anesthesia. But previous work by the team has indicated patients can tolerate it.

"This is very exciting," Gupta said, adding that the safety data so far looks good, too.

Some patients showed mild bleeding, with small amounts of blood in the urine.

Dr. William Roberts, a professor of urology at the University of Michigan, also described the work as exciting.

"This certainly looks as safe, or safer than, shock wave lithotripsy," he said.

Whether burst waves could be more effective is unclear, but Roberts said that if the procedure can be done in the urologist's office, that would be a big advantage.

None of that means the technology would help everyone with kidney stones. Roberts noted that while 19 patients were treated, a similar number entered the study but could not receive the ultrasound treatment: Some had stones that were too deep, for instance, or were obstructed by a rib or the bowel.

Still, Roberts said, even if only certain patients could have the procedure, its potential to be "more accessible" would be a boon.

But Dr. Joseph Vassalotti, chief medical officer of the National Kidney Foundation, said that while the procedure is "promising," most of the study patients were of normal body mass index (BMI), which makes breaking up stones with shock wave therapy easier.

"Low enrollment of obese patients is important not only because obesity is common in the U.S., but also because obesity is a technical limitation to performance of [ultrasound burst and shock wave therapy]," Vassalotti said.

Since earlier work suggests the burst wave approach is tolerable, patients might not need pain medication afterward to deal with the procedure itself, Roberts said—though they might need a pain reliever like acetaminophen (Tylenol) if passing the fragments proves uncomfortable.

The study team said it has begun studies to test the approach in patients who arrive in the emergency department with kidney stone pain. The technology has also been licensed to SonoMotion Inc., which is developing a commercial version and conducting its clinical trials.

More information: The Urology Care Foundation has a patient guide on kidney stones.

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02

Hydrogel is designed to remove every bit of those "blasted" kidney stones

Although some kidney stones can be treated with medication, larger ones are often broken up with an endoscopic laser. A new hydrogel is now claimed to be capable of removing even the smallest of the resulting fragments, instead of leaving them to possibly cause more problems.

Currently, in a procedure known as laser lithotripsy, a long thin endoscopic tube is inserted into the urethra, up to the point where the kidney stone is present. Guided by a fiber optic camera within that tube, a surgeon then utilizes an integrated laser to break the stone up into multiple pieces.

The larger of those pieces can be manually retrieved via a tiny extendable grasping tool, but the smaller ones are typically just left in place, in hopes that they will be naturally passed in the urine. Unfortunately, passing them may be painful, plus there's the chance that they could become problematically larger before they're able to be passed.

Seeking a more effective alternative, scientists at German startup Purenum – which is a spinoff of the Fraunhofer Institute for Manufacturing Technology and Advanced Materials – developed the two-part hydrogel. Here's how it works …

After a stone has been laser-broken and the larger fragments have been removed in the usual manner, a doctor endoscopically dispenses a proprietary blue-dyed liquid that flows around the remaining smaller fragments. A yellow-dyed catalyst liquid is then added, which causes the blue liquid to form into a continuous piece of elastic gel that encompasses all the fragments.

A piece of the hydrogel with encapsulated kidney stone fragments, following removal from the kidney

Plenum GmbH

That gel can then be endoscopically grasped and pulled out of the body, through the urethra. In the lab, it's possible to subsequently dissolve the gel, releasing the stone fragments for analysis.

Following the completion of clinical trials, it is hoped that the hydrogel should be launched in the German market in the second quarter of this year, under the trade name mediNiK-basic.

Sources: Fraunhofer, Plenum

03

Removing the smallest of kidney stone fragments during endoscopy using a hydrogel

Kidney stones are often removed via an endoscopic procedure. If a stone is too large, the urologists break it into pieces using a laser. The larger pieces can be removed with a grasping instrument, but this is not possible for the smaller fragments - instead, they remain in the kidney in the hope that they will leave the body naturally. In the future, doctors will be able to remove even the smallest of stone fragments from the kidney during endoscopy using a hydrogel. This biocompatible 2-component system was developed by Purenum GmbH, a spin-off of the Fraunhofer Institute for Manufacturing Technology and Advanced Materials IFAM.

Kidney stones are a common condition around the world. According to the German health insurance company AOK, ten percent of Germans will experience a kidney stone at some point in their lives. The size of the stones varies - at their worst, they can be as large as a walnut. The risk factors that can lead to the formation of a kidney stone include an unbalanced diet, a lack of exercise, and insufficient fluid intake. Kidney stones can be treated with medication or with minimally invasive therapies; as the technical possibilities continue to evolve, urologists are opting more and more frequently for endoscopic procedures. The endoscope is inserted into the kidney via the urinary tract to locate the stones and remove them in a targeted manner. If the kidney stone is larger than five millimeters - i.e., larger than the natural urinary tract - it must be broken into pieces using a laser. These pieces vary in size: The larger ones can be removed with a grasping instrument, but the smaller ones are too tiny to be grasped. Within a few months, the fragments that remain in the kidney can grow into a large stone and cause complications once again.

Plenum GmbH decided to tackle this problem. Manfred Peschka and Prof. Ingo Grunwald founded the company as a spin-off of Fraunhofer IFAM in Bremen back in December 2017. By participating in the GO-Bio funding program for biotechnology startups offered by the German Federal Ministry of Education and Research (BMBF), they were able to secure the funding they needed to launch their company successfully.

Biocompatible hydrogel encapsulates kidney stone fragments in seconds

The product that the two researchers have developed to combat the tiny stone fragments is a hydrogel made from biocompatible materials. 

It consists of two liquid components that have been dyed blue and yellow to ensure a good color contrast. 

This allows the surgeon to control dispensing in an extremely precise manner. 

The blue component is applied first, then flows around and wets the stone fragments. Following this, 

the yellow component is added. Application is extremely straightforward as the two components do not need to be mixed. 

Within a few seconds, the addition of the yellow component produces a gel that is solid enough to hold the small stone fragments inside. 

It is also elastic enough to be grasped with a grasping instrument and pulled through narrow channels (such as an endoscope). 

This makes it easy for the surgeon to pull the gel containing the stone fragments out of the kidney via the endoscope. 

After the operation, it can be dissolved easily to analyze the stones. 

"We intend to launch the gel on the German market in the second quarter of this year under the name mediNiK®-basic," explains Manfred Peschka, CEO of Purenum GmbH.

100% stone removal possible with mediNiK®

The term "stone-free" is not precisely defined - there are various definitions. 

And there have not been any systematic studies conducted among patients to provide information about the size of the stones retrieved during operations."

Prof. Ingo Grunwald, CTO at Plenum

He continues: "To that end, we are currently conducting a study at five different locations. 

Once it has been completed, this study will underpin our promise that.

with mediNiK®, we can remove more small stone fragments than would be possible without the use of our hydrogel.

The product is also attracting international interest, with Purenum GmbH receiving inquiries from all over the world.

There are no comparable products out there at the moment - mediNiK® is a world first in the field of urology," says Prof. 

Ingo Grunwald, a biologist. His colleague Manfred Peschka adds: 

"Our success is due in no small part to Fraunhofer IFAM. Without the exceptional support of Institute Director Prof. Bernd Mayer, Purenum GmbH would not exist."

Adhesive to replace screws and plates

Plenum GmbH's research activities extend beyond mediNiK®: 

In the BMBF-funded "media glue" project, the two researchers and their colleagues are looking at adhesive formulations that could be suitable for bonding bone fragments. Complicated bone fractures around joints result in small bone fragments that cannot currently be fixed. The vision behind this research project is that one day, it will be possible to incorporate these small fragments into the healing process as well. The aim is to restore full movement of the joint once the fracture has healed completely. Looking further ahead, there is even the possibility of using an adhesive on large bones as a replacement for plates, screws, and nails. This would eliminate the need to carry out a second operation to remove the osteosynthesis material. The two founders agree that this still belongs in the realm of science fiction for now, but quickly add: "If you want to achieve something, you have to set yourself ambitious goals and accept that you might fail. We're.