Drug – bio-affecting and body treating compositions – Radionuclide or intended radionuclide containing; adjuvant... – Molecular bilayer structure
Patent
1993-11-24
1994-11-22
Hollinden, Gary E.
Drug, bio-affecting and body treating compositions
Radionuclide or intended radionuclide containing; adjuvant...
Molecular bilayer structure
424 5, 424 9, 424722, 514576, 514922, A61B 5055, A61K 4904
Patent
active
053667220
DESCRIPTION:
BRIEF SUMMARY
This invention relates to contrast media, in particular non-ionic X-ray contrast media.
Contrast media may be administered in medical imaging procedures, for example X-ray, magnetic resonance and ultrasound imaging, to enhance the image contrast in images of a subject, generally a human or non-human animal body. The resulting enhanced contrast enables different organs, tissue types or body compartments to be more clearly observed or identified. In X-ray imaging the contrast media function by modifying the X-ray absorption characteristics of the body sites in which they distribute; magnetic resonance contrast media generally function by modifying the characteristic relaxation times T.sub.1 and T.sub.2 of the nuclei, generally water protons, from the resonance signals of which the images are generated; and ultrasound contrast media function by modifying the speed of sound or density in the body sites into which they distribute.
Clearly however the utility of a material as a contrast medium is governed to a large extent by its toxicity and any other adverse effects it may have on the subject to which it is administered. Since such media are conventionally used for diagnostic purposes rather than to achieve a direct therapeutic effect, when developing new contrast media there is a general desire to develop media having as little as possible an effect on the various biological mechanisms of the cells or the body as this will generally lead to lower animal toxicity and lower adverse clinical effects.
The toxicity and adverse effects of a contrast medium are contributed to by the components of the medium, e.g. the solvent or carrier as well as the contrast agent and its components (e.g. ions where it is ionic) and metabolites.
The following major contributing factors to contrast media toxicity and adverse effects have been identified:
Thus in coronary angiography, for example, injection into the circulatory system of contrast media has been associated with several serious effects on cardiac function, efforts sufficiently severe as to place limitations on the use in angiography of certain contrast media.
In this procedure, for a short period of time a bolus of contrast medium rather than blood flows through the circulatory system and differences in the chemical and physicochemical nature of the contrast medium and the blood that it temporarily replaces can give rise to undesirable effects, e.g. arrhythmias, QT-prolongation, and, especially, occurrence of ventricular fibrillation and reduction in cardiac contractile force.
Contrast media generally fall into two groups, the so-called ionic and non-ionic contrast media. In these the contrast agent, in solution, is respectively in ionic form or in molecular or particulate form.
Most conventional X-ray contrast media contain as the contrast agent an iodine containing material. (Iodine which has a relatively high atomic weight accordingly has a relatively large cross-section to X-rays).
Thus the contrast medium used in angiography may have an iodine concentration as high as 250-450 mg I/ml and at that concentration range ionic contrast agents of ratio 1.5 (such as diatrizoate, iothalamate, ioxithalamate, iodamide and metrizoate) have an osmolality 5 to 9 times that of normal human plasma, ionic contrast agents of ratio 3 (e.g. ioxaglate) or non-ionic contrast agents of ratio 3 (e.g. metrizamide, iopromide, iopentol, iopamidol and iohexol) have an osmolality about a half as large, and non-ionic contrast agents of ratio 6 (e.g. iotrolan and iodixanol) have an osmolality about quarter that of the ratio 1.5 ionic contrast agents at the same iodine concentration. Ratio 6 non-ionic contrast agents may even be used at iodine concentrations where they are hypotonic so that normal plasma ions and other conventional osmoactive agents may be added to produce isotonicity with normal plasma. By "ratio 3" in the above paragraph it is meant that the ratio of iodine atoms to contrast agent particles (i.e. ions or molecules) is 3. Ratio 1.5 ionic and ratio 3 non-ionic contrast agents ge
REFERENCES:
patent: 4283381 (1981-08-01), Speck et al.
patent: 4364921 (1982-12-01), Speck et al.
patent: 4426371 (1984-01-01), Pfeiffer et al.
patent: 4649050 (1987-03-01), Veech
patent: 4663166 (1987-05-01), Veech
patent: 4963344 (1990-10-01), Gries et al.
patent: 5011925 (1991-04-01), Rajagopalan et al.
Almen et al., Acta Radiologica Diagnosis, 17 (1976), 439-448.
Morris, Investigative Radiology, 23, 205-208, 1988.
Ralston, Investigative Radiology, 23, S140-143, 1988.
Zucker, Investigative Radiology, 23, S340-345, 1988.
Simon et al., AJR, 114, 810-816, 1972.
Piao et al., Investigative Radiology, 23, 466-470, 1988.
Kozeny et al., Am. Heart J., 109, 290 (1984).
Almen Torsten
B.ANG..ANG.th Laars
Oksendal Audun
Hollinden Gary E.
Nycomed Imaging AS
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