Rapid-scan NMR angiography
US4800889A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 6, 1987 |
| Grant date | Jan 31, 1989 |
| Priority date | — |
| Expiry date | Apr 6, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R33/563
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method for providing a nuclear magnetic resonance (NMR) angiographic image substantially only of moving spins associated with fluid flow in a living organism sample having a cardiac cycle at a cardiac rate, and immersed in a main static magnetic field, commences by nutating the spins by a preselected amount .alpha. less than 90.degree., in the initial part of each of a pair of imaging sequences. The repetition time interval T.sub.R between sequential nutations occurs at a rate greater than the cardiac rate. After each nutation, a pair of alternating-polarity flow-encoding signal pulses are generated in a first magnetic field gradient impressed upon the sample, with each of the flow-encoding pulses in the first sequence of each pair having a polarity opposite to the polarity of the like-positioned flow-encoding pulse in the second sequence of each pair. The NMR response echo signal is acquired and the difference in the data from the pair of sequences is used to display at least one projection angiographic image.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.