The Possibility for Iodine Concentration Determination in a Phantom with Known Titers of an Iodine-Containing Contrast Agent, by Using Dual-Energy Computed Tomography

Objective : to study the capabilities of single-source dual-energy computed tomography (DECT) in quantifying the concentration of iodine in solutions. Material and methods . Single-source DECT was performed using a phantom containing a set of 5 tubes with a different titer of the iodine-containing contrast agent Iopamidol. Further, the obtained images were used to construct iodine maps; and the concentration of iodine was measured within the volume of the titrated contrast agent. Results. Despite a high correlation between the measured iodine concentration in solution with the true concentration (Pearson's correlation coefficient r = 0.98; p < 0.01), there is a measurement error that was 4.8 to 23% at different dilutions. Conclusion. Signal-source rapid voltage switching DECT does not allow precise measurements of the true concentration of iodine in solution. To eliminate measurement errors in further in vivo studies using singlesource DECT, it may be that attention must be paid to the measurement of normalized iodine concentration.