TSU receives a patent for a frostbite treatment device

29 October 2019

TSU radiophysicists have improved their method of treating frostbitten limbs using weak microwave radiation and improved their setup, and have received a new patent for it. The scientists have made microwave radiation more uniform so that the overchilled limb warms up evenly. They also suggested that simultaneously with microwave heating, the upper layer of the skin be forced to cool, so that the deep vessels are revealed first and only then the superficial ones. This technique helps avoid amputation.

The method and device for treating frostbitten limbs are being developed by a team of scientists led by Professor Grigory Dunaevsky at the Department of Radio Electronics of the Faculty of Radiophysics and the Laboratory of Electronics at the Siberian Institute of Physics and Technology. The supervising doctor is Professor Evgeny Gavrilin, Doctor of Medical Science. At the moment, this is the only device in the world designed to treat deep frostbite.

The scientists have proposed limb warming with a weak microwave field. As a rule, during frostbite, people begin to intensively warm the limb, and the vessels closest to the skin surface open quickly, begin to promote blood and lymph, and the vessels inside are frozen. There is a rupture of blood vessels, necrosis, and often amputation. Weak microwave radiation is able to quickly warm the overchilled limb to its full depth, which avoids that sad consequence. However, warming up the entire limb at the same time was not easy, because the radiation in the microwave chamber is inhomogeneous - at one point it is stronger, at another it is weaker. Radiophysicists have solved this problem using mathematical modeling.

- When you heat a cutlet in a home microwave, the cutlet spins. If you do not twist it, then it will overheat in some place, and in another place it will remain unheated - this is due to the heterogeneity of the microwave field. In our case, the fields are used hundreds of times weaker, but the problem of heterogeneity persists, - explains Grigory Dunaevsky. - A person with a frostbitten limb cannot be twisted, so we are looking for ways to make the field itself change its picture so that the heating is uniform. Using mathematical modeling, we were able to analyze the field distribution in various modes and propose a technical solution to make the field more uniform.

As a result,  scientists have significantly modernized the installation for the treatment of overchilled limbs. To the microwave chamber, which carries out heating, and a flexible sleeve that isolates the patient and staff from radiation, radiophysicists introduced rotating re-emitters, which destroy stationary field inhomogeneities and provide more uniform heating. They also added a cooling system for the upper layer of the skin.

Microwave radiation is attenuated when it penetrates the limbs. And we need to open the deep vessels first, and leave the outer ones unaffected. We achieve this by cooling the outer layer, microwave heating, and of course drug therapy, intensive warming from the inside. Yes, we cool the limb affected by the cold so that all layers slowly and carefully become defrosted, moreover sequentially, starting from the deepest, and not vice versa, - said Grigory Dunaevsky.

The scientists have already received the fifth patent as part of their project. The first four defended the proposed method of treating frostbite with microwave fields and the first versions of devices that implement this method.