| 摘要 |
Non-invasive therapeutic treatment and/or quantitative evaluation of bone tissue are performed in vivo, by subjecting bone to an ultrasonic acoustic signal pulse of finite duration, and involving a composite sine-wave signal consisting of plural discrete frequencies that are spaced in the ultrasonic region to approximately 2 MHz; the excitation signal is repeated substantially in the range 1 to 1000 Hz. In a quantitative evaluation, the composite sine-wave signal is supplied to one of two transducers on opposite sides of the bone, and the signal received by the other transducer is processed (a) to sequentially average the most recently received given number of successive signals to obtain an averaged per-pulse signal and (b) to produce a Fourier transform of the averaged per-pulse bone-transmitted signal. In a separate operation not involving the bone, the same transducers are subjected to the same excitation, reception and processing, wherein the transducers are exposed to a medium of known acoustic properties and path length, all to the end of producing a reference Fourier transform which is processed with the Fourier transform of the bone-transmitted signal, to yield an evaluation or measurement. In a therapeutic treatment, the transducer supplied by the composite sine-wave signal is thus supplied for a period or periods of time, and with a magnitude, as may be prescribed by the physician for a given patient. |
