Cr-HIDA (Chromium diethyl HIDA meglumine) is a substance with paramagnetic characteristics that has been tested in animals for the use as a hepatobiliary MRI contrast agent.

See also Hepatobiliary Contrast Agents, Paramagnetic Substance, Paramagnetism.

(Dy) The Dysprosium chelates are analogs of the extracellular gadolinium chelates, with substitution of the dysprosium ion for the gadolinium ion and offers advantages in application on first pass studies. The use of a dysprosium-based contrast agent (Dy-type) instead of a gadolinium-type (Gd-type) is an alternative in cases of a disrupted blood brain barrier. Because of its much smaller T1 enhancement, this contrast agent should give more accurate perfusion calculations in brain MRI.

Short name: ECIII-60, central moiety: Gd3+
A non-porphyrin paramagnetic chelate with capabilities as a multipurpose T1-relaxivity necrosis avid MRI contrast agent.

See also Necrosis Avid Contrast Agent.

Short name: ECIV-7, central moiety: Gd3+
A non-porphyrin paramagnetic chelate with capabilities as a multipurpose T1-relaxivity necrosis avid MRI contrast agent.

See also Necrosis Avid Contrast Agent.

EP-2104R is a molecularly targeted MRI contrast agent for high resolution blood clot imaging within half an hour of injection. This gadolinium based small peptide has high affinity and specificity for human fibrin.
The thrombus agent is a new class of contrast medium for the diagnostic of, e.g. deep venous thrombosis, carotid artery blood clots, coronary artery blood clots and pulmonary embolism. Fibrin is an excellent target for a molecular imaging contrast agent, since it is present in arterial and venous clots at high concentrations (20-100 μM), and is a target for fibrinolytic therapy.
Due to financial problems, the developer EPIX Pharmaceuticals, Inc. had to shut down all operations. As a consequence, the development of EP-2104R is discontinued.