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Electromagnetic Tomography (EMT) measurement systems with low power consumption, high performance in terms of measurement accuracy and the capability of handling numerous antennas are needed for widely applied EMT. A highly modular approach for such a system is described in this paper. The shown concept allows to measure the required S-parameters, as needed for imaging of attenuative test objects, on any number of antennas simultaneously. This reduces total measurement time, without degradation of measurement accuracy. The presented concept has been realized as a prototype for 32 antennas and experimentally verified using a measurement chamber.

Statistics show, that stroke is one of the main causes of death worldwide, and reliable and fast diagnosis is key to recovery. Modern medical imaging devices provide intricate detail, but lack portability and are in some cases invasive. This paper presents a multiport vector network analyzer (MPVNA) measurement system for electromagnetic tomography (EMT) — an alternative medical imaging technique that complements more established methods. The portability of the system allows stroke to be detected very soon after occurrence. The architecture of the MPVNA enables parallelization of hundreds of measurements, which supports realtime operation without compromising measurement performance. Given the high attenuation caused by the human head and the limited signal power allowed in medical applications, the system is designed to measure signals at power levels as low as −150 dBm.

Imaging modalities based on electromagnetic tomography (EMT) have become a field of increasing interest and research in recent years. EMTensor GmbH is focused on the application of EMT technology to detect and identify stroke in human brain. In this work, first imaging results based on a 3D reconstruction of a human head phantom featuring a hemorrhagic stroke model are presented. The results have been obtained with the second generation of EMTensor brain scanner, which uses a spherical chamber topology and 177 ceramic loaded waveguide antennas. This investigation illustrates the ability of EMTensor technology to reconstruct relatively large and highly shielded 3D objects together with small contrast inhomogenities placed inside.

Electromagnetic Tomography (EMT) is a novel imaging modality with clinically viable potentials, being capable for fast functional imaging. The technology, when matured, might present an effective supplement to current imaging technologies for an assessment of functionality of brain tissue with unique time resolution in a range of dozens of msec together with decent spatial resolution. We have re-designed EMT imaging technology towards brain imaging and developed novel EMT scanner for human brain imaging. The scanner was used in initial clinical studies for diagnostic of stroke. First EMT tomographic human brain imaging results are presented here.