Surgery – Diagnostic testing – Detecting nuclear – electromagnetic – or ultrasonic radiation
Reexamination Certificate
1998-04-15
2001-11-06
Lateef, Marvin M. (Department: 3737)
Surgery
Diagnostic testing
Detecting nuclear, electromagnetic, or ultrasonic radiation
C600S443000
Reexamination Certificate
active
06312379
ABSTRACT:
FIELD OF THE INVENTION
This invention generally relates to ultrasound imaging systems. In particular, the invention relates to an ultrasound system and method for generating waveforms for harmonic imaging.
BACKGROUND OF THE INVENTION
Ultrasound imaging systems generate images of a body. One type of imaging is harmonic imaging. Ultrasound signals or pulses are transmitted at fundamental frequencies, and echo signals are received by a transducer. The echo signals are filtered to obtain signals associated with harmonic frequencies.
The signals associated with harmonic frequencies are generated through non-linear propagation and scattering within the body. For example, the signals are generated by non-linear scattering from contrast agents. Non-linear contrast agents are described for example by V. Uhlendorf, et al., in “Nonlinear Acoustical Response of Coated Microbubbles in Diagnostic Ultrasound” (1995 Ultrasonic Symposium, pp. 1559-1562). Such agents possess a fundamental resonant frequency. When they are insonified with high intensity ultrasonic energy at this fundamental frequency, they radiate ultrasonic energy at a harmonic of the fundamental frequency as well as at the fundamental frequency. Such contrast agents are often used to highlight regions containing blood loaded with the contrast agent. For example, in the case of a blood-filled chamber of the heart, the borders of the chamber can be distinguished more easily when contrast agents are used. Since the contrast agent generates harmonic ultrasound energy, echoes at the fundamental frequency from tissue or fluid containing no contrast agent may be eliminated by filtering at a receive beamformer.
Other than contrast agents, another source of harmonic energy is nonlinear propagation. As the ultrasonic burst propagates through the body, the burst distorts. The distortion corresponds to the shifting of energy to harmonic frequencies. As the burst propagates, more harmonic signals are generated. The harmonic signals are scattered from tissue and other structures in the body. Some of the harmonic signals impinge upon the transducer.
Another source of harmonic energy is system hardware nonlinearity. For example, high-voltage transmit circuitry may introduce harmonic energy in the transmit pulse before application to the transducer for transmission. Nonlinearity of the transducer may also add to harmonic content in the transmitted signal.
For contrast agent imaging, the signals output by the receive beamformer preferably include substantially only information from contrast agents (nonlinear scattering) and structure within the body (nonlinear propagation). The present invention is directed to improvements to reduce the harmonic information associated with structures in the body and system nonlinearity for harmonic imaging, whether imaging tissue or contrast agents.
SUMMARY OF THE INVENTION
This invention relates to improvements to a method for harmonic imaging of a target, which method comprises the steps of (a) transmitting ultrasonic energy at a fundamental frequency, (b) receiving reflected ultrasonic energy at a harmonic of the fundamental frequency and (c) generating an image responsive to the reflected energy at the harmonic.
According to a first aspect of this invention, the transmitting step includes the step of pre-distorting at least one of a plurality of waveforms as a function of a non-linearity. In various embodiments, the non-linearity may comprise a device non-linearity, a waveform propagation non-linearity, and combinations thereof.
According to a second aspect of this invention, the transmitting step includes the step of transmitting a waveform comprising a fundamental spectral component and a harmonic spectral component from a transducer. An attenuation normalized peak of the harmonic spectral component is reduced at a region spaced from the transducer as compared to the peak at a region adjacent to the transducer.
According to a third aspect of this invention, the transmitting step includes the step of transmitting a pre-distorted waveform from a transducer. The pre-distorted waveform includes a harmonic spectral peak suppressed by about 4 dB or more at a region of interest spaced from the transducer as compared to a harmonic spectral peak at the region associated with transmission of a waveform comprising a fundamental spectral component adjacent said transducer.
According to a fourth aspect of this invention, the transmitting step includes the step of transmitting a waveform comprising a positive pulse spatially defined by first and second zero values. A positive peak amplitude of the positive pulse is a first distance from the first zero value that is less than half a second distance between said first and second zero values.
REFERENCES:
patent: 4712037 (1987-12-01), Verbeek et al.
patent: 4771792 (1988-09-01), Seale
patent: 5040537 (1991-08-01), Katakura
patent: 5111823 (1992-05-01), Cohen
patent: 5115809 (1992-05-01), Saitoh et al.
patent: 5190766 (1993-03-01), Ishihara
patent: 5195520 (1993-03-01), Schlief et al.
patent: 5215680 (1993-06-01), D'Arrigo
patent: 5219401 (1993-06-01), Cathignol et al.
patent: 5255683 (1993-10-01), Monaghan
patent: 5285788 (1994-02-01), Arenson et al.
patent: 5325858 (1994-07-01), Moriizumi
patent: 5358466 (1994-10-01), Aida et al.
patent: 5380411 (1995-01-01), Schlief
patent: 5410205 (1995-04-01), Gururaja
patent: 5410516 (1995-04-01), Uhlendorf et al.
patent: 5417214 (1995-05-01), Roberts et al.
patent: 5425366 (1995-06-01), Reinhardt et al.
patent: 5433207 (1995-07-01), Pretlow, III
patent: 5438554 (1995-08-01), Seyed-Bolorforosh et al.
patent: 5456255 (1995-10-01), Abe et al.
patent: 5456257 (1995-10-01), Johnson et al.
patent: 5469849 (1995-11-01), Sasaki et al.
patent: 5479926 (1996-01-01), Ustuner et al.
patent: 5482046 (1996-01-01), Deitrich
patent: 5523058 (1996-06-01), Umemura et al.
patent: 5526816 (1996-06-01), Arditi
patent: 5558092 (1996-09-01), Unger et al.
patent: 5560364 (1996-10-01), Porter
patent: 5577505 (1996-11-01), Brock-Fisher et al.
patent: 5579768 (1996-12-01), Klesenski
patent: 5579770 (1996-12-01), Finger
patent: 5580575 (1996-12-01), Unger et al.
patent: 5601086 (1997-02-01), Pretlow, III et al.
patent: 5608690 (1997-03-01), Hossack et al.
patent: 5617862 (1997-04-01), Cole et al.
patent: 5632277 (1997-05-01), Chapman et al.
patent: 5675554 (1997-10-01), Cole et al.
patent: 5678554 (1997-10-01), Hossack et al.
patent: 5696737 (1997-12-01), Hossacke t al.
patent: 5706819 (1998-01-01), Hwang
patent: 5724976 (1998-03-01), Mine et al.
patent: 5740128 (1998-04-01), Hossack et al.
patent: 5995450 (1999-11-01), Cole et al.
patent: 6016285 (2000-01-01), Wrighte et al.
patent: 6056943 (2000-05-01), Schutt
patent: 0 770 352 A1 (1997-05-01), None
patent: WO 98/20361 (1998-05-01), None
Pi Hsien Chang, et al., “Second Harmonic Imaging and Harmonic Doppler Measurements with Albunex.” IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, vol. 42, No. 6, Nov. 1995.
Marc Gensane, “Bubble population measurements with a parametric array.” J. Acoustical Society of America, 95 (6), Jun. 1994.
Ken Ishihara, et al., “New Approach to Noninvasive Manometry based on Pressure Dependent Resonant Shift of Elastic Microcapsules in Ultrasonic Frequency Characteristics.” Japanese J. of Applied Physics, vol. 2 (1988).
V.L. Newhouse, et al., “Bubble size measurements using the nonlinear mixing of two frequencies.” J. Acoustical Society of America, 75 (5), May 1984.
“Small Spheres Lead to Big Ideas.” Research News, Science vol. 267, Jan. 20, 1995.
Abstracts Journal of the American Society of Echocardiography, vol. 8, No. 3 pp. 345-346, 355, 358-364.
Deborah J. Rubens, MD, et al., “Sonoelasticity Imaging of Prostate Cancer: In Vitro Results.” Radiology, vol. 195, No. 2, 1995.
B. Schrope, et al., “Simulated Capillary Blood Flow Measurement Using a Nonlinear Ultrasonic Contrast Agent.” Ultrasonic Imaging 14 (1992).
Fred Lee, Jr., MD et al., “Sonoelasticity Imaging: Results in in Vitro Tissue Specimens.” Radiology, vol. 181, No. 1 (1991).
Kevin J. Parker, P
Bradley Charles E.
Hedberg David J.
Holley Gregory L.
Napolitano Dave
Newell Lawrence J.
Acuson Corporation
Brinks Hofer Gilson & Lione
Lateef Marvin M.
Patel Maulin
Summerfield, Es Craig A.
LandOfFree
Ultrasonic harmonic imaging system and method using waveform... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Ultrasonic harmonic imaging system and method using waveform..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Ultrasonic harmonic imaging system and method using waveform... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2590273