MRI Contrast Agent
MRI contrast agents are a group of contrast media used to improve the visibility of internal body structures in magnetic resonance imaging (MRI). The most commonly used compounds for contrast enhancement are gadolinium-based. MRI contrast agents alter the relaxation times of atoms within body tissues where they are present after oral or intravenous administration. In MRI scanners sections of the body are exposed to a very strong magnetic field, a radiofrequency pulse is applied causing some atoms (including those in contrast agents) to spin and then relax after the pulse stops. This relaxation emits energy which is detected by the scanner and is mathematically converted into an image. The MRI image can be weighted in different ways giving a higher or lower signal.
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