Investigation of mouse conductance catheter position deviation effects on volume measurements by finite element models

The conductance catheter system is used to measure the instantaneous ventricular conductance, and real-time ventricular volumes is then determined by converting the measured conductance to volume. In fact, two different conductance-to-volume conversion equations for conductance catheters have been proposed, the Baan´s classic equation and Wei´s nonlinear equation. The accuracy of this volume estimation method is limited by several factors, such as the deviation of the catheter position inside the ventricle. The effects of the mouse catheter radial and longitudinal position deviations on the measured conductance are investigated with finite element models. Moreover, the capacities of the two conversion equations to calibrate the error induced by the catheter position variation are evaluated and compared. According to the simulation results, the error-calibrated capacity of the nonlinear conversion equation is better.