Radiography contrast agents

Molecular and cellular processes were visualized by X-ray contrast agents long before the term molecular imaging became popular and even before the advent of early CT (Table 1). Because of the above-mentioned limitations in the sensitivity of contrast detection by X-ray radiography, the latter can only visualize high capacity transport mechanisms and the nonspecific uptake of particles by specialized cells. 

Soft, silvery metal whose isolation is difficult. Ytterbium fluoride is added to dental fillings (as X-ray contrast agent). Ytterbium is a constituent of rust-free special steels. Yb2Co13Fe3Mn holds the magnetic world record, but is too expensive for commercial purposes. The element is occasionally applied in nuclear medicine and radiography. It also activates phosphors that convert infrared rays into visible light. 

BaS04 used as contrast agent for radiography and MRI and in bone cements used for the fixation of joint prostheses, Ba inhibits K flux through potassium ion channels Radiation therapy for carcinomas... 

Practically all available iodinated extracellular X-ray contrast agents have been encapsulated into liposomes using different lipids and methods of preparation. Table 1 gives a short and intentionally incomplete overview of some of the approaches. The first liposomal contrast agent preparation that was tested in humans contained diatrizoate [48]. The injected dose was up to 0.5 ml kg k The preparation was effective even in plain radiography where lesions down to 0.8-1.0 cm could be detected in patients. However, adverse events such as fever and hyperthermia, which occurred in 30% of the patients, limited further use. We have incorporated iopromide into MLVs that were prepared from phosphatidyl choline (PC), cholesterol and stearic acid at a molar ratio of 4 5 1 using the ethanol-evaporation technique [44]. The liposomes can be stored freeze-dried and they are reconstituted before use by... 

Adjuncts used in addition to contrast agents in diagnostic radiography, under patient group directions, include laxatives, drugs to relax the bowel, normal saline and topical anaesthesia. 

CH13 CONTRAST AGENTS AND ADJUNCTS TO RADIOGRAPHY Table 13.5 Miscellaneous adjuncts to radiography... 

Loughran, C.F. (1993) Intravenous Urography - injection of contrast agents by radiographers. Clinical Radiography, 47, 368. 

In addition, since 2003, podiatrists, physiotherapists and radiographers have been amongst those health care professionals who are allowed to supply and administer medicines under PGDs. This has proved particularly useful in certain situations. For example PGDs are used for the provision of medicines to counter the side effects of contrast agents used in diagnostic radiography. 

Many organic compounds containing normal iodine ( I) are used as radiopaques (X-ray contrast agents) in the radiography of the area where each is... 

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