Influence of Iodinated Magnetic Resonance Contrast Media and Isotope 99mTc on Changes of Computed Tomography Number

The purpose of the study was to identify how isotope and magnetic resonance imaging (MRI) contrast media impact on noise to computed tomography (CT) examination. For the study, divide the phantoms to two groups: 1) saline, saline + different kinds of contrast agent without Tc-99m administration; 2) Tc-99m administration: saline, saline + different kinds of contrast agent with Tc-99m administration. CT contrast agent was used for Iopamidol (R) and Dotarem. And MRI contrast agent was used for Primovist (R) and Gadovist (R). To obtain an image, we used CT scanner. With an obtained image, we set the 1 cm(2) region of interest in the middle of bottle to measure the noise and CT number. As a result, there was no difference in CT number before and after inserting 99mTc into all contrast media including Normal Saline. However, when it comes to Noise, there was a difference before and after inserting Tc-99m into every contrast media except MRI contrast media such as Primovist (R) and Gadovist (R).