Calibration Capacity of the Conductance-to-Volume Conversion Equations for the Mouse Conductance Catheter Measurement System

The conductance catheter system is used to measure instantaneous ventricular conductance, and real-time ventricular volume is then determined by converting the measured conductance to volume. Two conductance-to-volume conversion equations for the conductance catheter system have been proposed: Baan´s linear equation and Wei´s nonlinear equation. In fact, the accuracy of this volume estimation method is limited by several factors, such as the catheter position deviation. The effects of the mouse catheter position deviations on the volume-conductance relationships are investigated with cylindrical finite-element models and mouse left ventricular models. The accuracy and calibration capacity of the two conversion equations for estimating volume are evaluated and compared. According to the comparison results, the performance of the nonlinear conversion equation is better.