Abstract: In the NMR imaging of a subject comprising administering to such subject a composition containing an image-modifying effective amount of an image enhancer, permitting the enhancer to move through the subject, and after a time interval taking an NMR image of the subject, the improvement which comprises employing as said enhancer a complex of a paramagnetic polyvalent metal and a partial amide and/or ester of diethylenetriaminepentaacetic acid. The complexes are new.

Abstract: Radioactive metal ion chelates of N,N'-bis-(pyridoxal-5-phosphate)-alkylenediamine-N,N'-diacetic acids, N,N'-bis-(pyridoxal-5-phosphate)-1,2-cycloalkylenediamine-N,N'-diacetic acids, and N,N'-bis-(pyridoxal-5-phosphate)-1,2-arylenediamine-N,N'-diacetic acids, the corresponding monophosphate compounds and monoacetic acid compounds, and their salts and esters form stable, highly soluble chelates with paramagnetic metal ions, and are highly effective agents for radiopharmaceutical imaging. Preferred contrast agents are radioactive metal ion such as technetium-99m and indium-111 ion chelates of N,N'-bis-(pyridoxal-5-phosphate)ethylenediamine-N,N'-diacetic acid, N,N'-bis-(pyridoxal-5-phosphate)trans-1,2-cyclohexylene-diamine-N,N'-diace tic acid, N,N'-bis-(pyridoxal-5-phosphate)trans-1,2-arylenediamine-N,N'-diacetic acid, and the soluble calcium salts thereof.

Abstract: In the NMR imaging of a subject comprising administering to such subject a composition containing an image-modifying effective amount of an image enhancer, permitting the enhancer to move through the subject, and after a time interval taking an NMR image of the subject, the improvement which comprises employing as said enhancer a complex of an oxamine and a polyvalent paramagnetic metal, e.g. ferrioxamine. Novel complexes of trihydroxamic acids, optionally N-acylated, with polyvalent metals other than iron, are also described.

Abstract: Homologs of Diester-DTPA-Paramagnetic compounds (such as dimethyl acetyl diethylene triamine triacetic acid) provide excellent contrast agents for magnetic resonance imaging (MRI). The magnetic dipole generated by the unpaired electron within the paramagnetic (PM) atom, causes a local reduction in the bulk magnetic field of the MRI system. The resulting shorting of the T1 (spin lattice) relaxation time in the local hydrogen protons within the area of interest, causes an intense "free induction signal" and a corresponding modulation in the collected scanning data. The tissue or organ of interest appears on the MRI display highlighted in white. Background tissue is displayed as darker or lower intensity greys. The ester homologs replace two carboxylic acids to form functional ester groups on the DTPA chelator. The homologs cause the Diester-DTPA-PM contrast agents to go into solution readily, and promotes organ selectivity.

Abstract: Homologs of Diamide-DTPA-Paramagnetic compounds (such as diamido acetyl diethylene triamine triacetic acid) provide excellent contrast agents for magnetic resonance (MR) imaging. The magnetic dipole generated by the unpaired electron within the paramagnetic (PM) atom, causes a local reduction in the bulk magnetic field of the MR system. The resulting shorting of the T1 (spin lattice) relaxation time in the local hydrogen protons within the area of interest, causes an intense "free induction signal" and a corresponding modulation in the collected scanning data. The tissue or organ of interest appears on the MR display highlighted in white. Background tissue is displayed as darker or lower intensity greys. A surface highlighted image of the small and large intestine may be obtained by venous injection of the diamide contrast agent. The contrast agent is formed by replacing two carboxylic acids on the DTPA chelator with functional amide groups.

Abstract: The Ferrioxamine (FOM) family of chelates and amide homologs thereof provide excellent contrast agents for magnetic resonance (MR) imaging. The magnetic dipole generated by unpaired electrons within the paramagnetic Fe(III) atoms, cause a local reduction in the bulk magnetic field Bz of the MR system. The resulting shorting of the T1 (spin lattice) relaxation time in the local hydrogen protons within the area of interest, causes an intense "free induction signal" and a corresponding modulation in the collected scanning data. The contrast agent within the tissue or organ of interest causes the tissue to appear on the MR display as a high intensity or white area. Background tissue is displayed as darker or lower intensity greys.FOM does not penetrate the blood-brain-barrier under normal circumstances; and is therefore useful in detecting the extravasation of arterial blood in the extravascular space during cerebral hemorrhaging and in the endema fluid surrounding tumors.