US5143069A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Diagnostic method of monitoring skeletal defect by in vivo acoustic measurement of mechanical strength using correlation and spectral analysis
Assignee: Orthosonics Inc
•
Filing: 1990-08-03
•
Granted: 1992-09-01
•
Expires: 2010-08-03
Abstract
Abstract A diagnostic method for determining in vivo mechanical strength and structural integrity of hard tissues such as bones, in a non-invasive and non-dramatic manner. The method separates ultrasound energy affected by surrounding soft tissues, and thus permits unbiased determination of ultrasound parameters that represent the hard tissues. The mechanical strength of hard tissues is then determined on the basis of the ultrasound parameters, including the amount of energy propagated, the velocity of the ultrasound and the degree of dispersion together with the characteristic response of the hard tissues.
Inventors
- 👤 Seo J. Kwon
- 👤 J. Lawrence Katz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 08:21
CPC Classifications
G; G01; G01H; G01H5/00; A; A61; A61B; A61B8/00; A61B8/08; A61B8/0875; G01N; G01N29/00; G01N29/04; G01N29/11; G01N29/34; G01N29/348
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
158 words
A method of measuring in vivo mechanical strength and structural integrity of hard tissues in a body having tissues, soft tissues and skin, comprising the steps of: (a) mounting spaced apart ultrasound transducers over the skin and propagating an ultrasound signal from one of said transducers along the hard tissues and surrounding soft tissues; (b) establishing a fixed reference signal for the ultrasound transducers; (c) receiving the propagated ultrasound signal at another of said transducers; (d) sorting the received propagated ultrasound signal according to a relative propagation delay time by correlating the received ultrasound signal with the fixed reference signal; (e) determining a velocity, a propagation energy and a degree of dispersion of the ultrasound signal propagated along the hard tissues and the surrounding soft tissues based upon the propagated ultrasound sorting of step (d); and (f) relating the velocity, propagated energy and degree of dispersion to the mechanical strength and the structural integrity of the hard tissues.
Claim 2
Independent Claim
158 words
A method of measuring in vivo mechanical strength and structural integrity of hard tissues in a body having tissues, soft tissues and skin, comprising the steps of: (a) mounting spaced apart ultrasound transducers over the skin and propagating an ultrasound signal from one of said transducers along the hard tissues and surrounding soft tissues; (b) establishing a fixed reference signal for the ultrasound transducers; (c) receiving the propagated ultrasound signal at another of said transducers; (d) sorting the received propagated ultrasound signal according to a relative propagation delay time by correlating the received ultrasound signal with the fixed reference signal; (e) determining a velocity, a propagation energy and a degree of dispersion of the ultrasound signal propagated along the hard tissues and the surrounding soft tissues based upon the propagated ultrasound sorting of step (d); and (f) relating the velocity, propagated energy and degree of dispersion to the mechanical strength and the structural integrity of the hard tissues.
Claim 3
Dependent Claim
30 words
A method according to claim 1, further comprising the step of: establishing an additional reference signal by monitoring the ultrasound signal propagated through a normal part of the hard tissues.
Claim 4
Dependent Claim
36 words
A method as claimed in claim 1, wherein step (d) comprises the substep of sorting the received propagated ultrasound signal propagated along the hard tissues and the received propagated ultrasound signal propagated along the soft tissues.
Claim 5
Independent Claim
184 words
A method of measuring mechanical strength and structural integrity of hard tissues in a body having hard tissues and soft tissues, said method comprising the steps of: (a) placing an ultrasound transmitter and a first ultrasound receiver over the body with a first distance therebetween; (b) placing a second ultrasound receiver over the body at a second distance less than the first distance from the ultrasound transmitter; (c) transmitting ultrasound into the body so as to propagate the transmitted ultrasound along the hard tissues and along the soft tissues; (d) generating a fixed reference signal by joining the ultrasound transmitter to one of the first and second ultrasound receivers; (e) receiving ultrasound propagated along the hard tissues and along the soft tissues at the first ultrasound receiver and at the second ultrasound receiver; (f) autocorrelating the received ultrasound signals and cross-correlating the received ultrasound signals with said fixed reference signal; (g) extracting the correlated received ultrasound propagated through the hard tissue from the correlated signals; and (h) obtaining the approximated frequency response and characteristic response of the hard tissues based upon the extracted ultrasound.
Claim 6
Independent Claim
184 words
A method of measuring mechanical strength and structural integrity of hard tissues in a body having hard tissues and soft tissues, said method comprising the steps of: (a) placing an ultrasound transmitter and a first ultrasound receiver over the body with a first distance therebetween; (b) placing a second ultrasound receiver over the body at a second distance less than the first distance from the ultrasound transmitter; (c) transmitting ultrasound into the body so as to propagate the transmitted ultrasound along the hard tissues and along the soft tissues; (d) generating a fixed reference signal by joining the ultrasound transmitter to one of the first and second ultrasound receivers; (e) receiving ultrasound propagated along the hard tissues and along the soft tissues at the first ultrasound receiver and at the second ultrasound receiver; (f) autocorrelating the received ultrasound signals and cross-correlating the received ultrasound signals with said fixed reference signal; (g) extracting the correlated received ultrasound propagated through the hard tissue from the correlated signals; and (h) obtaining the approximated frequency response and characteristic response of the hard tissues based upon the extracted ultrasound.
Claim 7
Dependent Claim
29 words
A method according to claim 4, wherein step (g) includes gating the received ultrasound in the time domain so as to pass only ultrasound propagated through the hard tissues.
Claim 8
Dependent Claim
22 words
A method according to claim 5, wherein step (g) includes a substep of determining the peak and dispersion of the correlated signals.
Claim 9
Dependent Claim
50 words
A method according to claim 6, wherein step (h) further includes a substep of performing a fast fourier transform (FFT) on said correlated signals to obtain an approximated power spectrum and an approximated cross spectrum of said correlated signals and performing division between them to obtain the approximated frequency response.
Claim 10
Dependent Claim
34 words
A method according to claim 6, wherein step (h) includes a substep of performing an inverse fast fourier transform (IFFT) on the approximated frequency response to obtain the characteristic response of the hard tissues.
Claim 11
Dependent Claim
61 words
A method according to claim 4, further comprising the steps of: determining a time for said ultrasound transmitted in step (b) to travel between the ultrasound transmitter, the first ultrasound receiver and the second ultrasound receiver; and determining the velocity of ultrasound based upon the time delay and the distance between the ultrasound transmitter and the first and second ultrasound receivers.
References Cited (Backward Citations)
US4941474A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-09-01 | 1996-03-02 | 1996-09-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-09-01 | 2000-03-02 | 2000-09-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-09-01 | 2004-03-02 | 2004-09-01 | $7700.00 | Window Closed / Lapsed |