Intravenous contrast agents used in MRI are distributed in the extracellular spaces of the body before being excreted. In this sense they are similar to iodinated X-ray contrast media. However, contrast agents used for MRI are quite different from conventional radiographic contrast media in structure and function and there is no known cross sensitivity between these types of contrast agents. Common MRI contrast agents use metal ions (e.g., gadolinium or manganese) complexed with organic molecules.
Gd-DTPA, an ionic linear molecule complex (gadopentetate dimeglumine) was the first marketed MRI contrast agent. Although the osmolality of this substances can be relatively high (up to 1940 mOsm/kg H2O) compared with plasma, adverse reactions and side effects are very rare. The used doses are smaller compared with radiographic contrast media.

See also Nonionic Intravenous Contrast Agents, Dotarem®, and Magnevist®.

The magnetic isocenter is the center point of a magnetic field, the origin of the coordinate system (x, y, z) = (0, 0 ,0). In case of a cylindrical bore magnet type, the magnetic isocenter is at the center of the bore.

A microscopic group of spins, which resonate at the same frequency. The spin precesses around a circle in the xy-plane and the net magnetization is the length, amplitude or magnitude of the magnetization vector Mxy: the quantity normally represented on a pixel-by-pixel basis in a MR image (thus amplitude or magnitude image).

ISOL Technology participated in the pioneering the Korea's MRI development since the early 1980's. In spite of the rapidly changing business environment, and severe competition in the overall medical market, ISOL Technology has grown steadily each year and has established itself as a major provider of Magnetic Resonance(MR) Imaging Systems in Korea.
ISOL Technology also has the largest market share of the domestic bone densitometry equipment sales and is currently in the early stages of development of the 61 channel MCG (Magnetocardiography) system with the R and D funds from the Korean Ministry of Commerce, Industry and Energy.

MRI Scanners:

0.35T to 0.5T:
1.5T:
3T:

Isomers are molecules with the same chemical formula and often with the same kinds of bonds between atoms, but in which the atoms are arranged differently.

See also Isotope.