Diamide-DTPA-paramagnetic contrast agents for MR imaging
US4687659A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 13, 1984 |
| Grant date | Aug 18, 1987 |
| Priority date | — |
| Expiry date | Nov 13, 2004 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T436/24
- WIPO fieldPharmaceuticals
- WIPO sectorChemistry
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. The homologs enable the Diamide-DTPA-PM contrast agents to go into solution readily, and promote organ selectivity.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.