Abstract: An ultrasonic imaging system including an aberration correction system uses a harmonic component of the fundamental transmitted frequency for imaging, or for aberration correction, or both. By properly selecting the frequency pass bands of filters used in the image signal path and in the aberration correction signal path operating advantages are provided. The aberration correction values may be calculated concurrently with image formation.

Abstract: An ultrasonic imaging system includes an ultrasonic transducer having an image data array and a tracking array at each end of the image data array. The tracking arrays are oriented transversely to the image data array. Images from the image data array are used to reconstruct a three-dimensional representation of the target. The relative movement between respective frames of the image data is automatically estimated by a motion estimator, based on frames of data from the tracking arrays. As the transducer is rotated about the azimuthal axis of the image data array, features of the target remain within the image planes of the tracking arrays. Movements of these features in the image planes of the tracking arrays are used to estimate motion as required for the three-dimensional reconstruction. Similar techniques estimate motion within the plane of an image to create an extended field of view.

Abstract: A medical diagnostic ultrasound imaging method and system insonify a tissue containing a contrast agent with ultrasonic transmit signals at a fundamental frequency f. Backscattered ultrasonic receive signals are acquired and filtered to emphasize frequency components between the fundamental frequency f and the second harmonic frequency 2f, and the filtered receive signals are processed for display. This filtering enhances the ability of the method and system to discriminate between contrast agent and adjacent tissue.

Abstract: An ultrasonic imaging system includes an ultrasonic transducer having an image data array and a tracking array at each end of the image data array. The tracking arrays are oriented transversely to the image data array. Images from the image data array are used to reconstruct a three-dimensional representation of the target. The relative movement between respective frames of the image data is automatically estimated by a motion estimator, based on frames of data from the tracking arrays. As the transducer is rotated about the azimuthal axis of the image data array, features of the target remain within the image planes of the tracking arrays. Movements of these features in the image planes of the tracking arrays are used to estimate motion as required for the three-dimensional reconstruction. Similar techniques estimate motion within the plane of an image to create an extended field of view.

Abstract: A medical diagnostic ultrasonic imaging system acquires receive beams from spatially distinct transmit beams. The receive beams alternate in type between at least first and second types across the region being imaged. The first and second types of receive beams differ in at least one scan parameter other than transmit and receive line geometry, and can for example differ in transmit phase, transmit or receive aperture, system frequency, transmit focus, complex phase angle, transmit code or transmit gain. Receive beams associated with spatially distinct ones of the transmit beams (including at least one beam of the first type and at least one beam of the second type) are then combined. In this way, many two-pulse techniques, including, for example, phase inversion techniques, synthetic aperture techniques, synthetic frequency techniques, and synthetic focus techniques, can be used while substantially reducing the frame rate penalty normally associated with such techniques.

Abstract: A method and system for imaging contrast agent within human or animal tissue, organs and/or blood is provided. Contrast agents, such as perfluorocarbon gas-filled albumin microbubbles which exhibit momentary contrast enhancement when exposed to high intensity ultrasound are injected into a patient. Periodic images are generated to avoid reduction in the contrast provided by the contrast agents due to ultrasound destruction. Between the periodic images, an M-mode image is substantially continuously updated to allow the user to better locate and maintain imaging of a region of interest, determine dynamic movement within the region of interest, access attenuation, determine an appropriate trigger point, and view perfusion of the contrast agent between the periodic images while minimizing destruction of contrast agent. In one embodiment, an ultrasound system alternates between triggered firings of a two-dimensional B-mode image and substantially continuous updating of an M-mode image.

Abstract: An ultrasonic imaging system includes an ultrasonic transducer having an image data array and a tracking array at each end of the image data array. The tracking arrays are oriented transversely to the image data array. Images from the image data array are used to reconstruct a three-dimensional representation of the target. The relative movement between respective frames of the image data is automatically estimated by a motion estimator, based on frames of data from the tracking arrays. As the transducer is rotated about the azimuthal axis of the image data array, features of the target remain within the image planes of the tracking arrays. Movements of these features in the image planes of the tracking arrays are used to estimate motion as required for the three-dimensional reconstruction. Similar techniques estimate motion within the plane of an image to create an extended field of view.

Abstract: An ultrasonic imaging system including an aberration correction system uses a harmonic component of the fundamental transmitted frequency for imaging, or for aberration correction, or booth. By properly selecting the frequency pass bands, of filters used in the image signal path and in the aberration correction signal path operating advantages are provided. The aberration correction values may be calculated concurrently with image formation.

Abstract: A medical diagnostic ultrasound imaging system and method modulate the image signal as a function of the ratio of the harmonic receive signal to the fundamental receive signal. Tissue harmonic backscatter differs substantially in spectral shape as compared to contrast agent backscatter, and this method allows improved discrimination between contrast agent and tissue backscatter.

Abstract: An ultrasound imaging system is programmed to acquire first ultrasonic image frames intermittently. These first frames, typically triggered frames synchronized with a selected portion of an ECG cycle, are optimized for high image quality of a contrast agent included in the tissue. The imaging system automatically acquires second ultrasonic image frames between at least some of the first frames. The second image frames are typically locator frames which are optimized for reduced degradation of the contrast agent. More of the second frames are acquired per unit time than first frames, and both the first and second frames are displayed, either superimposed over one another or in side-by-side relationship. In this way the user is provided with substantially continuous transducer locating information, yet contrast agent destruction between acquisitions of the first, triggered frames is reduced or eliminated.

Abstract: An ultrasonic imaging system includes an ultrasonic transducer having an image data array and a tracking array at each end of the image data array. The tracking arrays are oriented transversely to the image data array. Images from the image data array are used to reconstruct a three-dimensional representation of the target. The relative movement between respective frames of the image data is automatically estimated by a motion estimator, based on frames of data from the tracking arrays. As the transducer is rotated about the azimuthal axis of the image data array, features of the target remain within the image planes of the tracking arrays. Movements of these features in the image planes of the tracking arrays are used to estimate motion as required for the three-dimensional reconstruction. Similar techniques estimate motion within the plane of an image to create an extended field of view.

Abstract: A method and system for acquiring data in an ultrasound system are provided. A transducer is operatively connected to a transmit beamformer and a receive beamformer. The receive beamformer is configured to obtain a first value associated with a fundamental frequency interleaved with a second value associated with a harmonic frequency. A first transmit signal is transmitted at a first frequency. A first echo signal is received in response to the first transmit signal. At least the first value associated with the first frequency is obtained from the first echo signal. An interleaved second transmit signal is transmitted at the first frequency or a second frequency. A second echo signal is received in response to the second transmit signal. At least the second value associated with a third frequency is obtained from the second echo signal. Images are generated and displayed based on the at least one first value and the at least one second value.

Abstract: A method and system for acquiring data in an ultrasound system are provided. A transducer is operatively connected to a transmit beamformer and a receive beamformer. The receive beamformer is configured to obtain a first value associated with a fundamental frequency interleaved with a second value associated with a harmonic frequency. A first transmit signal is transmitted at a first frequency. A first echo signal is received in response to the first transmit signal. At least the first value associated with the first frequency is obtained from the first echo signal. An interleaved second transmit signal is transmitted at the first frequency or a second frequency. A second echo signal is received in response to the second transmit signal. At least the second value associated with a third frequency is obtained from the second echo signal. Images are generated and displayed based on the at least one first value and the at least one second value.

Abstract: A method and system for acquiring data in an ultrasound system are provided. A transducer is operatively connected to a transmit beamformer and a receive beamformer. The receive beamformer is configured to obtain a first value associated with a fundamental frequency interleaved with a second value associated with a harmonic frequency. A first transmit signal is transmitted at a first frequency. A first echo signal is received in response to the first transmit signal. At least the first value associated with the first frequency is obtained from the first echo signal. An interleaved second transmit signal is transmitted at the first frequency or a second frequency. A second echo signal is received in response to the second transmit signal. At least the second value associated with a third frequency is obtained from the second echo signal. Images are generated and displayed based on the at least one first value and the at least one second value.

Abstract: An ultrasonic imaging system including an aberration correction system uses a harmonic component of the fundamental transmitted frequency for imaging, or for aberration correction, or both. By properly selecting the frequency pass bands of filters used in the image signal path and in the aberration correction signal path operating advantages are provided. The aberration correction values may be calculated concurrently with image formation.

Abstract: An ultrasonic imaging system includes an ultrasonic transducer having an image data array and a tracking array at each end of the image data array. The tracking arrays are oriented transversely to the image data array. Images from the image data array are used to reconstruct a three-dimensional representation of the target. The relative movement between respective frames of the image data is automatically estimated by a motion estimator, based on frames of data from the tracking arrays. As the transducer is rotated about the azimuthal axis of the image data array, features of the target remain within the image planes of the tracking arrays. Movements of these features in the image planes of the tracking arrays are used to estimate motion as required for the three-dimensional reconstruction. Similar techniques estimate motion within the plane of an image to create an extended field of view.

Abstract: An ultrasound imaging system is programmed to acquire first ultrasonic image frames intermittently. These first frames, typically triggered frames synchronized with a selected portion of an ECG cycle, are optimized for high image quality of a contrast agent included in the tissue. The imaging system automatically acquires second ultrasonic image frames between at least some of the first frames. The second image frames are typically locator frames which are optimized for reduced degradation of the contrast agent. More of the second frames are acquired per unit time than first frames, and both the first and second frames are displayed, either superimposed over one another or in side-by-side relationship. In this way the user is provided with substantially continuous transducer locating information, yet contrast agent destruction between acquisitions of the first, triggered frames is reduced or eliminated.

Abstract: An ultrasound imaging method includes the step of transmitting two ultrasonic transmit pulses into a region. First components of the transmit pulses are inverted with respect to each other while second components of the transmit pulses are not. Received ultrasound pulses associated with the transmit pulses are summed to selectively cancel the harmonic or fundamental components. By properly selecting the inverted and noninverted portions of the transmit pulses, the transmit pulses may be made unipolar, or they may be pre-distorted to further reduce second harmonic energy associated with system or tissue non-linearities.

Abstract: An ultrasound imaging system of the type having a receive beamformer that acquires multiple receive beams from each respective transmit beam includes an azimuthal spatial filter which operates to correct for geometric distortions typically associated with such multi-beam imaging systems. This azimuthal spatial filter is responsive to input signals derived from the receive beams to generate a corrected signal output as a function of a selected set of receive beams and a set of filter weights. The filter weights are caused to vary in accordance with the azimuthal coordinates of the selected receive beams in order to improve performance.

Abstract: A method and an apparatus are provided for storage and retrieval of measured aberration correction values used in adaptive focus ultrasound imaging. The aberration correction values, corresponding to an aberration region in an imaged subject, are measured at a transmit focal depth. The measured aberration correction values, typically delays, from a measurement depth are stored in a geometric aberration transform (GAT.TM.) table and transformed to aberration correction values at other focal depths for correcting the focus of both transmit and receive beamformers. The transformation is accomplished by using a geometric aberration transform (GAT.TM.) index table which retrieves one or more aberration correction values in the table for any desired depth.