An element consists of atoms having the same structure and the same chemically reaction.
See also Magnetic Resonance Spectroscopy, Isomer, Isotope, Helium, and Gadolinium.
Mathematically, an element or member of a set is any one of the separate objects that make up that set. Elements in arrays (parallel arrangement of many identical items) are used in MRI coils.

See also Array Coil, Array Processor, and Array Spatial Sensitivity Encoding Technique.

Eovist® (other brand name Primovist™) is a organ specific MRI contrast agent for the imaging, detection and characterization of liver conditions, including liver tumors, cysts, as well as other malignant and benign lesions. It is a water-soluble ethoxybenzyl derivative of Gd-DTPA. This compound is taken up by the hepatocytes (approximately 30% of the dose goes to the hepatocytes) and is equally excreted renal and biliary in humans. Excretion of Gd-EOB-DTPA in the bile may also permit visualization of both the gall bladder and the bile ducts.
Eovist® brightens the signal of T1 weighted MR images immediately after contrast administration. Dynamic and accumulation phase imaging can also be performed after bolus injection of Eovist®. The hepatocytes uptake will increase the signal intensity of normal liver parenchyma at 10 to 20 minutes after injection. This results in improved lesion-to-liver contrast because malignant tumors (metastases, the majority of hepatocellular carcinomas) do not contain either hepatocytes or their functioning is hampered.

WARNING: Gadolinium-based contrast agents increase the risk for nephrogenic systemic fibrosis (NSF) in patients with acute or chronic severe renal insufficiency (glomerular filtration rate less than 30 mL/min/1.73m²), or acute renal insufficiency of any severity due to the hepato-renal syndrome or in the perioperative liver transplantation period.

See also Drug Development and Approval Process USA, Contrast Medium, Hepatobiliary Contrast Agents, Tumor Specific Agents and Molecular Imaging.

Short name: GN-1140, chemical compound: Gd-DTPA-DeA, central moiety: Gd, phase: II
Gd-DTPA-DeA [Welfide Corp., Osaka, Japan], a paramagnetic MR contrast agent with hepatobiliary excretion is under development for liver imaging. This hydrophilic gadolinium chelate is a derivative of Gd-DTPA.

Short name: Gd-BOPTA, generic name: Gadobenate dimeglumine
A paramagnetic MRI contrast agent (small molecular weight Gd-chelate) with 0.5 and 0.25 molar concentration.
The albumin-mediated relaxation enhancement may result in advantages for Gd-BOPTA over Gd-DTPA and other gadolinium agents in poorly vascularized, small, or lesions with low enhancement and in tumors with high concentrations of albumin. The substance is excreted partly by the kidneys (75-90%), partly by the biliary system (10-25%). The uptake in the liver is about 5% in humans. It is bolus injectable.

See Contrast Agents and MultiHance®.

Short name: (Gd-DTPA)-17, 24 cascade polymer, generic name: Gadomer-17, 24, central moiety: Gd2+, relaxivity: r1=11.9, B0=1.0 T, r2=16.5, Dose: 0.05 mmol/kg
An intravascular macromolecular MRI contrast agent with positive enhancement under development (Bayer Schering Pharma AG) for MR angiography and tumor differentiation. The synthetic dendrimer with large molecular weight (17kD - limits agent to vascular space) is linked to Gadolinium. The renal excretion is slowed to intermediate molecular size. In MRA a longer lasting venous and arterial enhancement was seen with Gadomer-17 due to the particular pharmacokinetics of this agent.

See also Tumor Specific Agents, and Intravascular Contrast Agents.