Noninvasive room temperature instrument to measure magnetic susceptibility variations in body tissue
US6208884A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 18, 1998 |
| Grant date | Mar 27, 2001 |
| Priority date | — |
| Expiry date | Aug 18, 2018 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61B5/05
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A probe instrument using room-temperature sensor(s) that can measure magnetic susceptibilities variations. The instrument has sufficient resolution to monitor paramagnetic materials in a human body, and preferably iron in a human liver by noninvasively examining patients with iron-overload diseases. The instrument includes room temperature magnetic sensors, and detects the sample, that is the tissue response to an alternating current field applied by an applied field coil. The sensors that can be used include magnetoresistive, fluxgate and magnetoinductive sensors. The applied field coil dimensions are chosen so that the applied field is optimized for maximum response from the liver while minimizing the effects due to the overlying abdominal tissue and at the same time not unduly increasing the sensitivity of the instrument to the lung. To minimize noise introduced in the sensor due to fluctuations in the applied field, the applied field is canceled at the position of the sensor, i.e. the real and imaginary parts of the applied field are canceled. To overcome variations in the sensor output due to fluctuations in the applied field, change in the ambient temperature and mechanical r…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.