Computer Simulation Based on the Electric Dipole Model: Analysis of the Factors Affecting the Amplitude and the Waveform of the Cat Colon Electrical Control Activity

The effects of electrode placement and inter-electrode distance on the cutaneous and endoluminal recordings of the electrical control activity ECA have not yet been studied adequately. We quantitatively examined the effects due to the probe placement and the inter-electrode distance on the ECA of the transverse cat colon by simulation, whether for cutaneuos probes or for floating endoluminal probes, with the following aims: to shed light on the optimal electrode configuration and to propose standardization of the procedure for recording colonic electrical activity. We applied our previously described modelling methodology to simulate the ECA generation. The simulation model was based on the electric dipole. The computer simulation clearly indicated that the electrode placement and the inter-electrode distance have a substantial impact on the cutaneous ECA recordings. In fact, the simulation indicated that for the cutaneous probe: the smallest possible distance between the probe and the orthogonal projection of the distal border of the transverse colon enhancing the ECA amplitude is 4 cm, and the optimal inter-electrode distance is 4 cm. Regarding the endoluminal probe, the computer simulation indicated that the distance of the electrodes from the axis of the transverse colon and the inter-electrode distance have an evident effect on the ECA amplitude and waveform whereas the distance between the probe and the distal border of the transverse colon has no appreciable effect.