Few people know that right in the centre of Brno is a place that is unique at least in the scale of Central Europe. It is located directly on the premises of the St. Anne´s University Hospital in Brno and it is an almost perfect Faraday cage, therefore a workplace that has the maximum possible shielding from electromagnetic waves located all around us. This special laboratory is located under the building of the International Clinical Research Center of St. Anne’s University Hospital Brno (FNUSA-ICRC) and was designed for the research of very sensitive signals generated by the human body, especially for the research of brain diseases and cardiovascular diseases.
The brain generates a very weak electrical activity, which is sensed from electrodes placed on the head and, in some cases, from electrodes inserted directly into brain tissue. Minimal interference with the sensed electrical activity of the brain by unwanted signals from the environment is very important both for clinical diagnostics and especially in the field of research. Recently, for example, it has been shown that pathological high-frequency activity can be found in well-sensed electrical activity of the brain, which can be used for better diagnosis in patients with epilepsy and, for example, for more accurate localization of epileptogenic pathological bearings. “Thanks to high-quality Faraday cages, we are able to locate the epileptic focus in the brain of patients with uncontrolled epilepsy significantly more accurately. We use a significantly better signal-to-noise ratio, which the Faraday cage provides us when sensing the electrical activity of the brain, and thus allows us to evaluate some modern electrophysiological phenomena, such as high-frequency oscillations. The surgery of a patient with epilepsy can thus be faster, more accurate, and ultimately more successful, “said Professor Milan Brázdil, head of the 1st neurological clinic of FNUSA.
In terms of electromagnetic waves, a clean environment together with a quality device for sensing the electrical activity of the brain plays a very important role. “Initially, we also used this room to measure the ECG signal that is generated by heart activity. We have found that part of the ECG signal contains high-frequency components that can be used for a very simple but accurate description of the electrical activation of the heart chambers. This finding enables more accurate diagnosis of patients in need of a special pacemaker, “said Pavel Leinveber, head of the FNUSA-ICRC Biomedical Engineering research team. Scientists from the Institute of Instrumentation of the Academy of Sciences of the Czech Republic, FNUSA-ICRC, the cardiology clinic of our hospital and the M&I company from Prague obtained an american patent for this technology for a more accurate diagnosis of heart disease.
The requirements of scientists for the best possible shading had to be taken into account during the construction of the building itself. At a depth of ten meters below the ground, a concrete base plate was created, however, because the groundwater level in these places is only a meter below the ground, water had to be permanently pumped out to prevent the container from moving. Only when the building itself had three floors, the load was sufficient and it was possible to complete the monolith. “This is a maintenance-free passive Faraday cage, there is no active elimination of interference. The walls are made of Mu-metal, an alloy with a high nickel content, which has an extremely high resistance to electromagnetic waves, ”explained Leinveber. The condition of a functional Faraday cage is also a quality grounding, which is formed by a system of four, interconnected ten-meter rods. “We will not find a place with such shielding of electromagnetic phenomena anywhere in the world in natural conditions. When we measured the area ten meters underground outside Faraday’s cage, whenever a tram passed around the hospital, it immediately affected the electromagnetic interference, “Leinveber explained.
At present, the premises are still used for research purposes, however, it is possible to find free capacity for other entities that would be interested in this unique workplace. “Apart from research teams from other institutions, there is great potential for companies involved in the development of measuring technology, for example. We would like to simply know that there are such unique spaces and it is possible to use them by agreement, “added Roman Polák from the FNUSA-ICRC Technology Transfer Department.