This fun ultrasound device shatters tumors remotely

In the past few months, the fight against cancer has made some big strides, and this ultrasound machine is one of them.

Although cancer has been documented in the scientific literature for years, it remains a major public health problem. But in recent years we have seen a significant acceleration of research in this area. Between pathways related to AI, cutting-edge robotic approaches, or the development of next-generation diagnostic solutions, the horizon is beginning to clear for both detection and treatment.

And today American researchers prove it again. Scientists from the University of Michigan presented a very beautiful work in which they managed to remotely “crush” tumors in mice.

The concept is not new; Today, almost half of cancer cases are treated with non-invasive techniques. Doctors often use X-rays, which, at low doses, are at the heart of a well-known medical imaging technique that allows you to explore the inside of the body.

In high doses, however, they are also particularly harmful to the cells. A property that requires careful handling of them, but which also allows them to be “weaponized” to damage a tumor or even kill it completely. We then speak of radiotherapy.

It’s an approach often used in addition to other techniques, such as chemotherapy or immunotherapy. It is of great clinical interest as it is more targeted than the latter and is therefore often less traumatic to the rest of the body.

But despite its benefits, radiation therapy is still relatively dangerous for healthy tissue. The goal of many researchers is therefore to develop a non-invasive technique with comparable effectiveness, but capable of targeting cancer cells while limiting collateral damage.

Ultra controlled mini detonations

In this case, University of Michigan researchers followed the ultrasound trail; this is called “histotripsy”. It’s an idea that has been explored many times before, as in these works from 2019. But they were often relatively abstract works; This time, they developed a working device prototype that could soon be incorporated into treatment protocols.

Positioned exactly outside the body, the device can bombard a tumor with ultrasound. Note, however, that this is not thermal destruction, but mechanical; In other words, it’s not about “cooking” the tumor, it’s about crushing it without even touching it.

The researchers play with the physical principle of cavitation. It is a complex phenomenon that plays a very important role in fluid mechanics. In short, the concept is based on a pressure difference. When the pressure of a liquid falls below a certain threshold at a certain point, a bubble forms and eventually implodes, creating a sometimes violent pressure wave.

For example, we can name mantis shrimp or pistol shrimp, both of which use this principle to hunt. They have an overdeveloped appendage that allows them to create extreme cavitation. This creates a bubble that has absolutely insane pressure and temperature; the detonation can reach 220 db and the bubble can heat up to 4800°C (!) for a split second! The impact is so intense that it can shatter incredibly hard grenades with a single impact, even killing prey instantly.

© Worlikar et. Section.

A safe, effective approach with few side effects

Numbers that say a lot about the destructive potential of well-controlled cavitation. The researchers therefore designed a device capable of creating a small cavitation; in this case they can achieve an accuracy of the order of a millimeter. This concept allows them to remotely “crush” cancer cells without damaging the remaining tissue.

The overall strategy is exactly the same as with radiation therapy; This technique can be self-sufficient, but it is above all about Rough up the tumor as much as possible to set the stage to other treatments. And the first results were quite impressive.

The team claims their device decimated up to 75% of cancerous tissue in rats with liver cancer. So it’s not a total eradication. But with a result that is largely sufficient for Improving the vital prognosis.Even if we don’t target the entire tumor, we can still force it to regress and reduce the risk of metastasis‘ explains bioengineering professor Zhen Xu.

© Marcin Szczepanski, Michigan Engineering

Of course, it’s still just rodents. In addition, this device has so far only been tested in connection with liver cancer. So it will be important to validate the concept in humans First. It must then be checked whether it can also be used for other types of cancer.

But for now all signals are green; the technological foundations are already in place. And this experience has shown that ultrasound-based therapy can be well deserved to integrate the arsenal of oncologists in the near future. Based on these encouraging results, the team will now propose to integrate their device into various clinical trials.

If these tests are conclusive, this technique could then be democratized; it would then offer an alternative or complementary treatment pathway to facilitate labor in a safe, effective manner and with minimal side effects.

The text of the study can be found here.

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