EP0248623A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Ultrasound scanning apparatus
Assignee: University of Washington
•
Filing: 1987-06-01
•
Granted: —
•
Expires: 2007-06-01
Abstract
Abstract Apparatus for deriving signals indicating a condition of tissue within a volume of a body comprising means (2) for launching spaced supersonic pulses into a body under examination and means (6) for detecting the power of supersonic waves scattered from locations along a plurality of known paths. Signals proportional to the squares of the amplitudes of the reflected waves are generated, and the squares are integrated to give the desired indication. Gain control means (42,44,48,50) are provided from compensating for changes in amplitude ofh scattered supersonic waves resulting from their passage through blood or tissue, the increased attenuation with frequency of the spectrum of the launched pulses (60) and the focussing of the launched pulses (62). Compensation (54) for ring-down and the attenuation of the chest wall is also provided.
Inventors
- 👤 Lewis J. Thomas Iii
- 👤 Thomas J. Hunt
- 👤 James G. Miller
- 👤 Hewlett E Melton, Jr.
- 👤 Thomas A. Shoup
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-23 14:41
CPC Classifications
G; G01; G01S; G01S7/00; G01S7/52; G01S7/52017; G01S7/52023; G01S7/52036; A; A61; A61B; A61B8/00; A61B8/08; G01N; G01N29/00; G01N29/04; G01N29/06; G01N29/0609; G01S7/52025; G01S7/52033
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
49 words
Apparatus for deriving signals indicating a condition of tissue within a volume of a body, comprising means (2) for launching pulses of supersonic pressure waves into a body under examination, and means (6) for detecting the power of supersonic waves scattered from locations along a pluarality of known paths.
Claim 2
Dependent Claim
49 words
Apparatus for deriving signals indicating a condition of tissue within a volume of a body, comprising means (2) for launching pulses of supersonic pressure waves into a body under examination, and means (6) for detecting the power of supersonic waves scattered from locations along a pluarality of known paths.
Claim 3
Dependent Claim
95 words
Apparatus as set forth in claims l, wherein said means (6) comprises means for converting pressure waves reflected from matter within a volume of said body into electrical signals, means for deriving amplitude signals proportional to the amplitudes of components of said electrical signals in either the time or frequency domain, means coupled to said latter means for deriving the squares of the amplitude signals, and means for summing said squares, thereby deriving a signal proportional to the integrated backscatter from said volume of the body, indicative of the condition of the tissue within it.
Claim 4
Dependent Claim
161 words
Apparatus as set forth in Claim 2 wherein said means for deriving said amplitude signals is comprised of sampling means (l4) for deriving samples corresponding to the amplitudes of successive samples of the electrical signals, arithmetic means (l6) coupled to said sampling means for deriving the squares of each sample, a summer (l8) having two inputs and an output, one input being coupled to the output of said arithmetic means (l6), a FIFO delay (20) coupled to the output of said arithmetic means, a subtractor (22) for subtracting a signal applied to a first input thereof from a signal applied to a second input thereof, said first input being coupled to said FIFO delay (20) and said second input being coupled to the output of said summer (l8), and the output of said subtractor (22) being coupled to the other input of said summer (l8), whereby the signal proportional to the intregrated backscatter appears at the output of said subtractor (22).
Claim 5
Dependent Claim
149 words
Apparatus as set forth in Claim 2 wherein said means for deriving said amplitude signals is comprised of sampling means (l4) for deriving samples respectively corresponding to amplitudes of samples of the electrical signals, arithmetic means (l6) coupled to the output of said sampling means for deriving the squares of said samples, said means for summing the squares comprising a subtractor (22) for subtracting a signal applied to a first input thereof from a signal applied to a second input thereof,said second input being coupled to the output of said arithmetic means (l6), a FIFO delay (20) coupled between said arithmetic means (l6) and said first input of said subtractor (22), and a summer (l8) having one input coupled to the output of said subtractor (22) and an output coupled to another input thereof, whereby the signal proportional to the integrated backscatter appears at the output of said summer.
Claim 6
Dependent Claim
164 words
Apparatus as set forth in Claim 2 where in said means for deriving said amplitude signals is comprised of sampling means (l4) for deriving samples respectively corresponding to the amplitudes of successive samples of the electrical signals, said means for deriving the squares comprising computation means (26) having first and second inputs and an output, said means providing at its output a signal equal to the square of a signal applied to its first input less the square of a signal applied to its second input, said first input being coupled to the output of said sampling means, a FIFO delay (20) coupled between said sampling means (l4) and said second input of said computation means, and summer (24) having first and second inputs and an output, said first input being coupled to the output of said computation means (26) and said second input being coupled to its output, whereby the signal proportional to the integrated backscatter appears at the output of said summer.
Claim 7
Dependent Claim
144 words
Apparatus as set forth in Claim 2 wherein said means for deriving said amplitude signals is comprised of sampling means (l4) for deriving samples corresponding to the amplitudes of successive samples of the electrical signals, said means for deriving the squares comprising an FFT (28) coupled to said sampling means (l4) said FFT supplying real and imaginary components of each of a plurality of frequencies represented by said samples, arithmetic means (30) for deriving signals equal to the sum of the squares of all of said real and imaginary components appearing at the output of said FFT at given times, and an integrator (34) for integrating the signals at the output of said arithmetic means (30) over the usable bandwidth of the frequency components at the output of said FFT, whereby the signal representing the integrated backscatter appears at the output of said integrator.
Claim 8
Dependent Claim
51 words
Apparatus as set forth in Claim 6 having at least one other series combination of an FFT (28ʹ), an arithmetic means (30ʹ) and an integrator (34ʹ) connected to the output of said sampling means whereby said signal for a range overlapping said range appears at the output of said latter integrator.
Claim 9
Dependent Claim
51 words
Apparatus as set forth in Claim 2 wherein said means for deriving said amplitude signals is comprised of a spectrum analyzer (40), and an integrator (34) is provided coupled to the output of said spectrum analyzer whereby the signal proportional to the integrated backscatter appears at the output of said integrator.
Claim 10
Dependent Claim
144 words
Apparatus as set forth in Claim 2 comprising means (2) for converting the supersonic waves into electrical waves, gain control means (4) for coupling the electrical waves, to said power detection means (6); said gain control means (4) being responsive to a gain control signal applied to an input thereof, means for deriving a gain control signal for application to said input, said latter means including means (42,48,50), for providing a first component for said gain control signal that would, if operating by itself, cause a given increase in gain with time when the amplitude of said electrical waves is greater than a reference value, and means (44) for providing a different componentfor said gain control signal that would, if operating by itself, cause a smaller increase in gain with time when the amplitude of said electrical waves is less than the reference value.
Claim 11
Dependent Claim
63 words
l0. Apparatus as set forth in Claim 9 further comprising means (52) for disabling said means (50.44) for providing said first and second components for said gain control signal for a given first period after the launch of each pulse, and means (54) for providing during said period a gain control signal component that causes said gain control means to provide zero gain.
Claim 12
Dependent Claim
72 words
Apparatus as set forth in Claim 9 further comprising means (52) for disabling said means (50,44) for providing said first and second components for said gain control signal during a period after the launching of each ultrasonic pulse when said electrical waves result from scatter from the chest wall and for providing a component for said gain control signal that causes a greater increase in gain with time than said given increase.
Claim 13
Dependent Claim
49 words
Apparatus as set forth in claim 9 further comprising means (62) for providing another compenent for saig gain control signal that, wehn combined with said first or second components, compensates for the change in amplitude of the electrical waves that would result from the focussing of the ultrasonic pulses.
Claim 14
Dependent Claim
56 words
Apparatus as set forth in claim 9 further comprising means (60) for providing another component for saig gain control signal that, when combined with said first or second components, compensates for the change in amplitude of the electrical waves that results from the increase in attenuation with frequency of the frequency components of a launched pulse.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.