Electromagnetic bone-assessment apparatus and method
US5782763A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 1, 1997 |
| Grant date | Jul 21, 1998 |
| Priority date | — |
| Expiry date | Jul 1, 2017 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61B5/7264
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
Non-invasive quantitative in-vivo electromagnetic evaluation of bone is performed by subjecting bone to an electrical excitation wave-form supplied to a pair of electrodes on opposite sides of a bony member, and involving a repetitive finite duration signal consisting of plural frequencies that are in the range 0 Hz-200 MHz. Signal-processing of a bone-current response signal and a bone-voltage response signal is operative to sequentially average the most recently received given number of successive bone-current and bone-voltage response signals to obtain an averaged per-pulse bone-current signal and an averaged per-pulse bone-voltage signal, and to produce their associated Fourier transforms. These Fourier transforms are further processed to obtain the frequency-dependent bone-admittance function. In a separate operation, the same electrodes respond to the same excitation signal via a medium of known electromagnetic properties and path length to establish a reference-voltage signal and reference-current signal, which are processed to produce their associated Fourier transforms. These two Fourier transforms are further processed to produce a frequency-dependent reference-admittance…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.