Y.A. Zakharchenko1, G.E. Plytkevich2, A.N. Tikhomirov3, N.V. Kalmykov4

1,2,3,4 FSAEI HE "Bauman Moscow State Technical University" (Moscow, Russia), (Russia)

3 Petrovsky National Research Center of Surgery (Russia)

1 ya_zakharchenko@mail.ru

Classical electroimpedance tomography of the lungs makes it possible to visualize changes in the resistivity of tissues in a section of the chest. The use of the differential approach is due to the linearization of the inverse tomography problem, which makes it possible to solve it in real time. The downside of this approach is that the absolute values of resistivity remain unknown. In addition, with a significant change in the resistivity of tissues, for example, during breathing or during heart movement, the assessment of the change in resistivity may also undergo nonlinear distortions.

The purpose of the work: estimation of the error in determining the resistivity of tissues in the area of the lungs, heart chambers and soft tissues when the resistivity of the lungs changes in the range from the functional residual volume to the vital capacity of the lungs.

The largest relative change in the coefficients of the reconstruction matrix is observed for the lungs themselves. For half of the leads, the change was more than 95%. For the soft tissues and chambers of the heart, the median relative change was 34.6% and 20.4%, respectively.

The results show that in electroimpedance tomography tasks that require quantitative compliance with resistivity estimates, such as monitoring ventilation or lung perfusion, it is necessary to take into account the non-linearity of the inverse tomography problem.

Zakharchenko Y.A., Plytkevich G.E., Tikhomirov A.N., Kalmykov N.V. Decomposition of surface thoracic impedance to partial impedances of internal tissues // Biomedical Radioelectronics. 2026. V. 29. № 6. P. 39−43. DOI: https://doi.org/10.18127/j15604136-202606-08

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