Abstract: An ultrasonic imaging method and apparatus are described for imaging the coronary arteries of the heart. The vascular system is infused with an ultrasonic contrast agent. A volumetric region of the heart wall including a coronary artery is three dimensionally scanned. A projection image of the volumetric region is produced from the scanning, providing a two dimensional contrast image of the coronary artery with the appearance of an angiogram. Preferably the coronary artery signals are segmented from contrast signals emanating from the myocardium and the heart blood pool so that the coronary arteries are clearly highlighted and distinct in the ultrasonic angiogram.

Abstract: An ultrasonic diagnostic imaging system receives fundamental frequency, harmonic contrast, and tissue harmonic echo information for image processing. The fundamental and harmonic signal content of the echo information is analyzed and the relative content of an output signal is adjusted as necessary to take advantage of the different characteristics of the different types of echo information present in the echo signal. The ultrasound system can produce images which are an adaptive blend of fundamental, tissue harmonic and harmonic contrast echo information.

Abstract: An ultrasonic diagnostic imaging system and method are described for performing nonlinear echo signal imaging with sum or difference frequency signal components. The sum or difference frequency components are produced by nonlinear effects of tissue or contrast agents and are advantageously separated from the fundamental transmit components of the echo signals by pulse inversion processing. The transmit frequency components are located at frequencies chosen so that the sum or difference frequency components to be used for imaging fall in the central, most sensitive, region of the transducer passband. The beam profiles of the sum or difference frequency components exhibit improved signal to clutter ratios and lateral resolution characteristics as compared to the transmit beam characteristics.

Abstract: An ultrasonic diagnostic imaging system and method are described for performing nonlinear echo signal imaging with harmonic and intermodulation product (sum or difference frequency) components. Both the harmonic and the intermodulation products are produced by nonlinear effects of tissue or contrast agents and both are advantageously separated from the fundamental transmit components of the echo signals by pulse inversion processing. The use of both nonlinear components can improve the signal to noise ratio of the ultrasonic images, and the two types of components can be blended or used in different regions of an image to offset the effects of depth dependent attenuation.

Abstract: Apparatus and methods are disclosed for the detection and imaging of ultrasonic contrast agents. Ultrasonic apparatus is provided for coherent imaging of ultrasonic contrast agents, and for detecting harmonic contrast agents. The inventive apparatus includes a dual display for simultaneously viewing a real time image which displays the location of the contrast agent and a triggered contrast image. Methods of contrast agent detection and imaging include the measurement of perfusion rate characteristics, multizone contrast imaging, multifrequency contrast imaging, tissue perfusion display, and high PRF contrast image artifact elimination.

Abstract: An ultrasonic imaging method and apparatus are described for imaging the coronary arteries of the heart. The vascular system is infused with an ultrasonic contrast agent. A volumetric region of the heart wall including a coronary artery is three dimensionally scanned. A projection image of the volumetric region is produced from the scanning, providing a two dimensional contrast image of the coronary artery with the appearance of an angiogram. Preferably the coronary artery signals are segmented from contrast signals emanating from the myocardium and the heart blood pool so that the coronary arteries are clearly highlighted and distinct in the ultrasonic angiogram.

Abstract: An ultrasonic imaging method and apparatus are described for imaging the coronary arteries of the heart. The vascular system is infused with an ultrasonic contrast agent. A volumetric region of the heart wall including a coronary artery is three dimensionally scanned. A projection image of the volumetric region is produced from the scanning, providing a two dimensional contrast image of the coronary artery with the appearance of an angiogram. Preferably the coronary artery signals are segmented from contrast signals emanating from the myocardium and the heart blood pool so that the coronary arteries are clearly highlighted and distinct in the ultrasonic angiogram.

Abstract: An ultrasonic imaging method and apparatus are described for imaging the coronary arteries of the heart. The vascular system is infused with an ultrasonic contrast agent. A volumetric region of the heart wall including a coronary artery is three dimensionally scanned. A projection image of the volumetric region is produced from the scanning, providing a two dimensional contrast image of the coronary artery with the appearance of an angiogram. Preferably the coronary artery signals are segmented from contrast signals emanating from the myocardium and the heart blood pool so that the coronary arteries are clearly highlighted and distinct in the ultrasonic angiogram.

Abstract: An ultrasonic imaging method and apparatus are described for imaging the coronary arteries of the heart. The vascular system is infused with an ultrasonic contrast agent. A volumetric region of the heart wall including a coronary artery is three dimensionally scanned. A projection image of the volumetric region is produced from the scanning, providing a two dimensional contrast image of the coronary artery with the appearance of an angiogram. Preferably the coronary artery signals are segmented from contrast signals emanating from the myocardium and the heart blood pool so that the coronary arteries are clearly highlighted and distinct in the ultrasonic angiogram.

Abstract: Nonlinear tissue or contrast agent effects are detected by combining echoes from multiple, differently modulated transmit pulses below the second harmonic band. The received echoes may even overlap the fundamental transmit frequency band. The modulation may be amplitude modulation or phase or polarity modulation, and is preferably both amplitude and phase or modulation. The present invention affords the ability to utilize a majority of the transducer passband for both transmission and reception, and to transmit pulses which are less destructive to microbubble contrast agents.

Abstract: An ultrasonic diagnostic imaging system and method are described for performing nonlinear echo signal imaging with harmonic and intermodulation product (sum or difference frequency) components. Both the harmonic and the intermodulation products are produced by nonlinear effects of tissue or contrast agents and both are advantageously separated from the fundamental transmit components of the echo signals by pulse inversion processing. The use of both nonlinear components can improve the signal to noise ratio of the ultrasonic images, and the two types of components can be blended or used in different regions of an image to offset the effects of depth dependent attenuation.

Abstract: Apparatus and methods are disclosed for the detection and imaging of ultrasonic contrast agents. Ultrasonic apparatus is provided for coherent imaging of ultrasonic contrast agents, and for detecting harmonic contrast agents. The inventive apparatus includes a dual display for simultaneously viewing a real time image which displays the location of the contrast agent and a triggered contrast image. Methods of contrast agent detection and imaging include the measurement of perfusion rate characteristics, multizone contrast imaging, multifrequency contrast imaging, tissue perfusion display, and high PRF contrast image artifact elimination.

Abstract: Nonlinear tissue or contrast agent effects are detected by combining echoes from multiple, differently modulated transmit pulses below the second harmonic band. The received echoes may even overlap the fundamental transmit frequency band. The modulation may be amplitude modulation or phase or polarity modulation, and is preferably both amplitude and phase or modulation. The present invention affords the ability to utilize a majority of the transducer passband for both transmission and reception, and to transmit pulses which are less destructive to microbubble contrast agents.

Abstract: Nonlinear tissue or contrast agent effects are detected by combining echoes from multiple, differently modulated transmit pulses below the second harmonic band. The received echoes may even overlap the fundamental transmit frequency band. The modulation may be amplitude modulation or phase or polarity modulation, and is preferably both amplitude and phase or modulation. The present invention affords the ability to utilize a majority of the transducer passband for both transmission and reception, and to transmit pulses which are less destructive to microbubble contrast agents.

Abstract: Apparatus and methods are disclosed for the detection and imaging of ultrasonic contrast agents. Ultrasonic apparatus is provided for coherent imaging of ultrasonic contrast agents, and for detecting harmonic contrast agents. The inventive apparatus includes a dual display for simultaneously viewing a real time image which displays the location of the contrast agent and a triggered contrast image. Methods of contrast agent detection and imaging include the measurement of perfusion rate characteristics, multizone contrast imaging, multifrequency contrast imaging, tissue perfusion display, and high PRF contrast image artifact elimination.

Abstract: An ultrasonic diagnostic imaging system and method are described which produce tissue harmonic images containing both fundamental and harmonic frequency components. Such a blended image takes advantage of the performance possible with the two types of ultrasonic echo information and can advantageously reduce near field clutter while improving signal to noise performance in the far field of the image.

Abstract: An ultrasonic diagnostic imaging system and methods are described which produce tissue harmonic ultrasonic images from harmonic echo components of a transmitted fundamental frequency. Fundamental frequency waves are transmitted by an array transducer to focus at a focal depth. As the transmitted waves penetrate the body, the harmonic effect develops as the wave components begin to focus. The harmonic response from the tissue is detected and displayed, while clutter from the fundamental response is reduced by excluding fundamental frequencies. The technique is especially useful for imaging the endocardial tissue of the heart.

Abstract: Pulse inversion harmonic separation is performed utilizing echoes from three or more pulses of alternating phase or polarity. Temporally different echoes of opposite phase or polarity are combined in pairs, which are in turn combined to form partial sums and a final sum in which fundamental frequency signal components are substantially eliminated. Preferably the signals are normalized to a common reference level. The inventive technique can be performed by a filter structure using weighting coefficients exhibiting a Gaussian variation.

Abstract: Perfusion of tissue such as the myocardium by a microbubble contrast agent is imaged in realtime by a multiple pulse technique which uses low power transmit pulses which are sufficient to elicit a harmonic response from the microbubbles but are not high enough in power to cause substantial destruction to the microbubbles. In a preferred embodiment the realtime microbubble image sequence is displayed in color, overlaid with a grayscale image of the surrounding tissue in the region being imaged.

Abstract: An ultrasonic diagnostic imaging system and method are provided for producing harmonic contrast images with harmonic components produced by the contrast agent with little interference from nonlinear tissue interaction. A method is described for developing predistorted ultrasonic transmit signals, the predistortion of which will be counteracted by the nonlinear effects of tissue and result in substantially linear waveforms at the location of the contrast agent. The echoes returned by the contrast agent will contain nonlinear components resulting from the interaction of a linear waveform with the agent, with reduced nonlinear components from nonlinear tissue effects.