The brain tissue is provided with a tight endothelial layer on vessels that acts as a filter for substances that reach the brain through the blood stream. This filter is called the blood brain barrier.
The blood brain barrier is responsible for the absence of contrast agent enhancement in normal brain tissue after administration of the iodinated or paramagnetic contrast media used in brain MRI and computed tomography (CT) diagnostic. The absence of contrast uptake in normal tissue provides the basis for differentiation from pathological brain tissue, which is conversely characterized by a disruption of the blood brain barrier.

See also Contrast Enhanced MRI, MRI Safety, Adverse Reaction.

The company is a member of the Bracco Group, a highly innovative healthcare group and world leader in global integrated solutions for the diagnostic medical imaging field. The Bracco Group is headquartered in Milan, Italy. Its North American operations consist of Bracco Diagnostics and Bracco Research USA, both located in Princeton, New Jersey. Bracco Diagnostics is one of the fastest growing developers and marketers of diagnostic pharmaceuticals in North America, with products for various imaging applications, including Isovue® (iopamidol - X-ray contrast agent), ProHance® (gadoteridol - MRI contrast agent), SonoVue® (ultrasound contrast agent) and nuclear medicine products.
Gadoteridol has been available in Europe and the USA for several years. Holder of the Marketing Authorization: Bracco International B.V. - Strawinskylaan 3051 - 1077 ZX Amsterdam The Netherlands. (Contact: Kirk Deeter, Phone: +NL-303-838-8708)

MRI Contrast Agents:

Short name: CMC 001, central moiety: Mn2+
CMC 001 is an orally administered MRI contrast agent in development for enhancement of the liver, bile ducts and gastrointestinal tract. Applications are screening of liver tumors/metastases, imaging of the biliary tract and it could be suitable for liver function studies by following the metabolism and excretion of manganese in the liver cells. Several advantages like better images, higher safety, lower costs and less inconvenience for the patient can be expected.
Animal experiments and clinical studies in humans Phase I and Phase II A, have shown excellent contrast enhancing properties with only minimal adverse effects. CMC 001 is under development by the Medicon Valley based CMC Contrast AB to receive a cost effective, safe and highly diagnostic MR contrast medium for abdominal MR imaging. Clinical studies in Phase III are started.

Some dyamides are under preclinical development as intravascular MRI contrast agents for blood flow perfusion.

Short name: Dy-DTPA-BMA, generic name: Sprodyamide, central moiety: Dy2+, contrast effect: T2*enhanced, relaxivity: r1=3.4, r2=3.8, B0=0.47,

Short name: Dy-DTPA, central moiety: Dy2+, contrast effect: T2*enhanced,

Short name: Albumin-(Dy-DTPA)x, central moiety: Dy2+, contrast effect: T2*enhanced.

The contrast agents are either renal or hepatically excreted media, which stay in the intravascular/extracellular tissue compartment. The enhancement in the blood continues for as long as the contrast agent remains in the blood stream.
E.g. Dotarem®, Magnevist®, Omniscan®, ProHance®.

See Contrast Medium, Contrast Agents and Blood Pool Agents.