Tracking system to monitor the position of a device using multiplexed magnetic resonance detection
US5353795A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 10, 1992 |
| Grant date | Oct 11, 1994 |
| Priority date | — |
| Expiry date | Dec 10, 2012 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R33/5617
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A tracking system employs magnetic resonance signals to monitor the position of a device such as a catheter within a subject. The device has a receiver coil which is sensitive to magnetic resonance signals generated in the subject. These signals are detected in the presence of magnetic field gradients and thus have frequencies which are substantially proportional to the location of the coil along the direction of the applied gradient. Signals are detected responsive to applied magnetic gradients to determine the position of the device in several dimensions. Sensitivity of the measured position to resonance offset conditions such as transmitter frequency misadjustment, chemical shift and the like is minimized by repeating the process a plurality of times with selected amplitudes and polarities for the applied magnetic field gradient. Linear combinations of the data acquired responsive to the different applied magnetic field gradients are computed to determine the position of the device in three orthogonal dimensions. The position of the device as determined by the tracking system is superimposed upon independently acquired medical diagnostic images.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.