Implantable marker with a leadless signal transmitter compatible for use in magnetic resonance devices
US7289839B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 30, 2002 |
| Grant date | Oct 30, 2007 |
| Priority date | — |
| Expiry date | May 10, 2025 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49194
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A leadless marker for localizing the position of a target within a patient. In one embodiment, the marker includes a casing, a resonating circuit, and a ferromagnetic element. The casing is configured to be positioned at a selected location relative to a target site in the patient; the casing, for example, can be configured to be permanently or semi-permanently implanted into the patient. The resonating circuit has an inductor within the casing comprising a plurality of windings of a conductor, but it does not have external electrical lead lines extending through the casing. The ferromagnetic element is at least partially within the inductor. The ferromagnetic element has a volume such that when the marker is in an imaging magnetic field having a field strength of 1.5 T and a gradient of 3 T/m, then the force exerted on the marker by the imaging magnetic field is not greater than gravitational force exerted on the marker.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.