MR method for exciting the nuclear magnetization in a limited volume
US6512941B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 22, 2000 |
| Grant date | Jan 28, 2003 |
| Priority date | — |
| Expiry date | Feb 12, 2021 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61B5/055
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The invention relates to a method of and a device for exciting the nuclear magnetization in a limited volume of an object to be examined, utilizing a microcoil (L) which is present in the volume and is attached, for example, to an interventional instrument during the formation of a magnetic resonance image of the object to be examined. The excitation of the nuclear magnetization is performed by at least one RF pulse whose frequency spectrum does not overlap the range of the spin resonance spectrum, so that no nuclear magnetization is excited outside the close range of the microcoil in the object to be examined. The microcoil, however, is provided with an active or passive circuit (for example, it is wired together with at least one capacitance (C) and a non-linear component (D1, D2) so as to form a non-linear resonant circuit) which locally generates an RF signal from the RF pulse. The RF signal overlaps the spin resonance frequency and causes excitation of the nuclear magnetization exclusively in the close range of the microcoil. After measurement and appropriate signal processing, this nuclear magnetization is used either to determine the position of the microcoil for reproductio…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.