Gynecologic electrical impedance tomograph

Abstract

Electrical impedance tomography extends to the new and new areas of the medical diagnostics: lungs, breast, prostate, etc. The feedback from the doctors who use our breast EIT diagnostic system has induced us to develop the 3D electrical impedance imaging device for diagnostics of the cervix of the uterus-gynecologic impedance tomograph (GIT). The device uses the same measuring approach as the breast imaging system: 2D flat array of the electrodes arranged on the probe with handle is placed against the body. Each of the 32 electrodes of the array is connected in turn to the current source while the rest electrodes acquire the potentials on the surface. The current flows through the electrode of the array and returns through the remote electrode placed on the patient's limb. The voltages are measured relative to another remote electrode. The 3D backprojection along equipotential surfaces is used to reconstruct conductivity distribution up to approximately 1 cm in depth. Small number of electrodes enables us to implement real time imaging with a few frames per sec. rate. The device is under initial testing and evaluation of the imaging capabilities and suitability of usage.

An electrical impedance tomography system for gynecological application GIT with a tiny electrode array

“…The smaller the EIT tomography system, the harder it is to connect electrodes and electronics. During the development of the system, we started with the former presented prototype (Korjenevsky et al 2010) with wires and external electronics, made several attempts to connect the electrode array to measuring electronics under the conditions with lack of space by different ways and then came up with a new prototype that will be discussed in the paper. Let us introduce the list of advantages and disadvantages which were found during the development.…”

“…The first prototype (Korjenevsky et al 2010) used wires to connect the electrode array to measuring electronics. The advantages (+) and disadvantages (-) are listed as follows.…”

“…It is a robust, fast, well-working real signal-to-noise condition algorithm, which provides static visualization and we have positive experience of its use for commercial, clinical application of the multifrequency EIT system MEM (Cherepenin et al 2002). The first version of the GIT prototype was proposed in our previous publication (Korjenevsky et al 2010).…”

Modified weighted back-projection algorithm (MWBP) for 3D electrical impedance mammography systems with the planar electrode array

“…The system scans the breast in two frequencies; 10 KHz and 50 KHz which can be used in fdEIM (frequency-difference EIM) in addition to static EIM using a reference set. In [30,31], the authors have used WBP algorithm to design a 3D EIT system with an small electrode array appropriate for gynecological applications.…”