N,N -Bis(2,3-dihydroxypropyl)-5-[N-(2-hydroxyethyl)-glycolamidol]-2,4,6-triiodoisopht halamide

Article Details

Citation
Copy to clipboard

Cheng KT

N,N -Bis(2,3-dihydroxypropyl)-5-[N-(2-hydroxyethyl)-glycolamidol]-2,4,6-triiodoisopht halamide

.

PubMed ID
20641970 [ View in PubMed
]
Abstract

N,N -bis(2,3-dihydroxypropy)-5-[N-(2-hydroxyethyl)-glycolamidol]-2,4,6-triiodoisophth alamide (ioversol) is a nonionic X-ray contrast agent used to aid the radiographic visualization of blood vessels, heart, head, and body (1). Ioversol is approved by the United States Food and Drug Administration for contrast enhancement in peripheral and coronary arteriography and left ventriculography and for computed tomographic (CT) imaging of the head and body (2). X-Ray imaging (planar and tomographic) techniques depend on tissue density differences which provide the image contrast produced by X-ray attenuation between the area of interest and surrounding tissues (3, 4). Contrast enhancement (opacification) with use of contrast agents increases the degree of contrast and improves the differentiation of pathological processes from normal tissues. Because iodine, an element of high atomic density, casuses high attenuation of X-rays within the diagnostic energy spectrum, water-soluble and reasonably safe iodinated contrast agents in intravenous injectable forms have been developed for clinical applications (5, 6). Water-soluble, intravenous X-ray contrast agents are generally organic iodine compounds that contain one or more tri-iodinated benzene rings (7, 8). When injected intravenously, they are largely distributed in the extracellular fluid space and excreted unchanged by the kidneys (9). Contrast enhancement of a region of interest depends on the route of administration, delivery of the agent to the area by blood flow, and the final iodine concentration in the region. There are two basic types of these compounds: ionic and nonionic agents. The first monomeric ionic compound in the form of the 2,4,6-triiodobenzene acetrizoic acid, was synthesized by Wallingford (5). Most ionic contrast agents are derived from the basic structures of 3,5-diamino-2,4,6-triiodobenzoic acid, 5-amino-2,4,5-triiodoisophthalic acid, or 2,4,6-tri-iodobenzene-1,3,5-tricarbonic acid. In addition to developing monoacidic ionic dimers, nonionic compounds have also been developed to improve the tolerability of these agents in patients. The basic strategy of developing nonionic agents is to eliminate the electrical charges in the structure, which will lead to a reduction in osmolality of the compound. Because osmolality is related to the number of particles in solution, the challenge is to reduce the number of particles and maintain the iodine concentration (10). This was generally achieved by conversion of the carboxyl groups to hydroxyalkylamide groups (11). Further improvement was made by replacing the amino sugar with aminoalcohols to produce heat-stable hydroxyalkylamides to allow product sterilization (12). Ioversol is a monomeric nonionic, tri-iodinated contrast agent that is characterized by relatively high hydrophilicity (13). Bonnemain et al. (14) discussed the concept of evenly distributed facial hydrophilicity, which led to the high hydrophilicity (log P octanol/water = -2.98) of ioversol. The current commercial formulations contain iodine concentrations of 160, 240, 300, 320 and 350 mg of iodine/ml (mg I/ml) with corresponding osmolality values (mOsm/g water) of 355, 502, 651, 702, and 792, respectively (2). The corresponding viscosity values (cps at 37 masculineC) are 1.9, 3.0, 5.5, 5.8, and 9.0, respectively.

DrugBank Data that Cites this Article

Drugs