Drug – bio-affecting and body treating compositions – Radionuclide or intended radionuclide containing; adjuvant... – Molecular bilayer structure
Patent
1992-11-06
1994-07-12
Hollinden, Gary
Drug, bio-affecting and body treating compositions
Radionuclide or intended radionuclide containing; adjuvant...
Molecular bilayer structure
424 4, 514974, A61K 4904
Patent
active
053286804
DESCRIPTION:
BRIEF SUMMARY
This invention relates to contrast media, especially to X-ray contrast media and more especially so-called non-ionic contrast media.
Contrast media generally fall into two groups, the so-called ionic and non-ionic contrast media. In these the contrast agent, in a carrier fluid, is respectively in ionic form or in molecular or particulate form.
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 into 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 the 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 of contrast media into the circulatory system has been associated with several serious effects on cardiac function, effects 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, reduction in cardiac contractile force and occurrence of ventricular fibrillation. There have been many investigations into these negative effects on cardiac function of infusion of contrast media into the circulatory system, e.g. during angiography, and means for reducing or eliminating these effects have been widely sought.
By way of reassurance it should be noted that modern low osmolar non-ionic contrast media do not generally present significant toxic or adverse effects and are thus fully suitable for most patients. There is however a particular desire for even more physiologically balanced contrast media for use when there is a possibility of prolonged exposure of tissue to the contrast media, e.g. where pools of contrast media may form for example as a result of stenosis, wedging of a catheter, occlusion due to PTCA (percutaneous transluminal coronary angioplasty) intervention.
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
REFERENCES:
patent: 1858142 (1932-05-01), Elizey
patent: 3175952 (1965-03-01), Bird
patent: 3325370 (1967-06-01), Holtermann et al.
patent: 3347746 (1967-10-01), Holtermann et al.
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.
Morris, Investigative Radiology, 23, Mar. 1988, 205-208.
Zucker et al., Investigative Radiology, 23, Suppl. 2, Nov. 1988, S340-S345.
Ralston et al., Investigative Radiology, 23, Suppl. 1, Sep. 1988, S140-143.
Almen, Acta Radiologica Diagnosis, 17, 1976, 439-448.
Piao et al., Investigative Radiology, 23, Jun. 1988, 466-470.
Simon et al., AJR, 144:810-816, 1972.
Tragardh et al., Investigative Radiology, 10, 3, 1975, 231-238.
Morris, Investigative Radiology, 23, Suppl. 1, Sep. 1988, S137-S-139.
Kozeny et al., Am. Heart Journal, 109:290, 1984.
Almen Torsten
Baath Lars
Jynge Per
Oksendal Audun N.
Hollinden Gary
Nycomed Imaging AS
LandOfFree
Contrast media comprising a non-ionic contrast agent with low le does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Contrast media comprising a non-ionic contrast agent with low le, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Contrast media comprising a non-ionic contrast agent with low le will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-394541