Abstract: A method and system for obtaining ultrasound data is provided. Two or more transducer elements are shorted or connected to the same transmit or receive channel for a single transmit or receive event. The affect of any grating lobes generated from shorting the transducer elements are minimized by receiving acoustic energy and then obtaining ultrasound data at a harmonic of a fundamental transmit frequency. No contrast agent is added during imaging. A multiplexer with a limited number of switches is used to short pairs of transducer elements together. Alternatively, a multiplexer with a limited number of switches is used to transmit or receive from spaced apertures, such as by connecting a channel to every second transducer element.

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: A digital transmit beamformer system with multiple beam transmit capability has a plurality of multi-channel transmitters, each channel with a source of sampled, complex-valued initial waveform information representative of the ultimate desired waveform to be applied to one or more corresponding transducer elements for each beam. Each multi-channel transmitter applies beamformation delays and apodization to each channel's respective initial waveform information digitally, digitally modulates the information by a carrier frequency, and interpolates the information to the DAC sample rate for conversion to an analog signal and application to the associated transducer element(s). The beamformer transmitters can be programmed per channel and per beam with carrier frequency, delay, apodization and calibration values. For pulsed wave operation, pulse waveform parameters can be specified to the beamformer transmitters on a per firing basis, without degrading the scan frame rate to non-useful diagnostic levels.

Abstract: An apparatus and method for processing ultrasound data is provided. The apparatus includes an interface operatively connected to a memory, a programmable single instruction multiple data processor (or two symmetric processors), a source of acoustic data (such as a data bus) and a system bus. The memory stores data from the processor, ultrasound data from the source, and data from the system bus. The processor has direct access to the memory. Alternatively, the system bus has direct access to the memory. The interface device translates logically addressed ultrasound data to physically addressed ultrasound data for storage in a memory. The translation is the same for data from both the processor and the source for at least a portion of a range of addresses. The memory stores both ultrasound data and various of: beamformer control data, instruction data for the processor, display text plane information, control plane data, and a table of memory addresses. One peripheral connects to the ultrasound apparatus.

Abstract: An ultrasonic probe that includes at least two ultrasonic arrays and allows three dimensional images to be constructed of the region examined by the probe in a precise and facile manner.

Abstract: A medical diagnostic ultrasound method and system for simultaneous phase correction of signal components at two frequency bands is provided. Simultaneous phase correction is performed, in part, during transmission of ultrasound waveforms and, in part, during reception of returning echoes. The phase between any two transmitted beams is adjusted by a first phase value. The phase between any two received beams is adjusted by a second phase value. Selection of the first and second phase values allows for simultaneous correction of signal components at two different frequency bands. For example, fundamental and second harmonic frequency bands are corrected for coherent imaging or processing. The phase corrections may account for different transmit and receive processes, such as fixed focus transmission and dynamic receive focusing.

Abstract: An ultrasound transducer having a field of view greater than 180.degree., and having a physical shape which permits it to be employed in the investigation and observation of the anatomy, or other body, object or region of interest, having limited access. A plurality of ultrasound transducer arrays are provided, each having a field of view defining an image plane, wherein the axis of each transducer array lies within its corresponding defined image plane. Preferably, the plurality of transducer arrays are positioned end-to-end and nonaxially aligned with the image planes of all transducer arrays coincident, and with each transducer array having a field of view of about 90.degree., whereby a resulting combined field of view greater than 90.degree. is produced.

Abstract: An ultrasonic imaging system includes an auxiliary processor that is connected to the imaging system by an open-standard, high-speed digital data channel. The system processor of the imaging system directs some processing tasks to the imaging system for execution in the conventional manner. Other processing tasks (often associated with computationally intensive applications) are automatically routed to the auxiliary processor for execution. The data channels between the system processor and the auxiliary processor allow high-speed exchange of live video information such that the identity of the processor performing a particular application is transparent to the user.

Abstract: A method and system for registration of multiple ultrasound images or frames of data are provided. The images are registered as a function of relative movement of the transducer. A feature or feature pattern, such as one or more structural edges, are identified in one image. The feature or feature pattern is represented by fewer than all of the data points within a frame of data. Based on the identification of a particular feature or feature pattern, relative motion is estimated by correlating the feature pattern with another image in various relative positions. The best correlation is selected. The motion is estimated by selecting a translation and rotation of the position associated with the best correlation. The frames of data are registered and compounded to generate the panoramic field of view image as a function of the estimated motion. The panoramic field of view image comprises a B-mode image, or a color Doppler image, or an image that is a combination of both. The imaging may be static or dynamic.

Abstract: The preferred embodiments include a method for manufacturing an end portion surrounding a catheter-mounted phased-array ultrasound transducer. The material used for the end portion can be altered to give the end portion focusing, defocusing, or non-focusing characteristics. In one preferred embodiment, a thermoplastic material is injection molded or insert molded around a phased-array ultrasound transducer carried at a distal end of a catheter. In another preferred embodiment, a thermoset material is used to form the end portion using a casting or transfer molding technique. In yet another preferred embodiment, the phased-array ultrasound transducer is placed into a pre-formed end portion. The pre-formed end portion can be adhesively-attached to the phased-array transducer and catheter. If the pre-formed end portion is made from a thermoplastic material, the end portion can be thermally melted to attach the end portion to the phased-array transducer and catheter.

Abstract: An ultrasound imaging system having an integrated touch-pad pointing device is provided. The touch-pad pointing device can be used to perform the functions currently performed by a trackball while overcoming the disadvantages commonly associated with trackballs. In addition to being integrated with the ultrasound imaging system, the touch-pad pointing device can also externally interface with the ultrasound imaging system, allowing the touch-pad pointing device to be easily added to existing ultrasound imaging systems that are not integrated with a touch-pad pointing device. Further, the touch-pad pointing device can be located on a remote user-interface device coupled with the ultrasound system to provide the further advantage of physically positioning the touch-pad pointing device closer to the user and away from the ultrasound machine.

Abstract: An ultrasonic imaging system and method provide a composite image having a near-field region and a far-field region that are displayed in a common imaging mode. The near-field region emphasizes received ultrasonic imaging at a harmonic of the fundamental of the transmit waveform, while the far-field region emphasizes received ultrasonic information at the fundamental frequency. In this way the advantages of harmonic imaging are obtained in the near-field without sacrificing penetration performance in the far-field.

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 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 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: Coherent data representing a plurality of two-dimensional regions that overlap as a function of the elevational beam width are obtained. The coherent data, such as in-phase and quadrature data, is filtered along an elevational dimension. The filtering adjusts the phase of the coherent data in the elevation dimension. Filtering effectively generates a Fourier transform of the coherent data along the elevational dimension, and adjusts the phase by multiplying by a spectral focusing function. Multiplying by the spectral focusing function results in a constant phase. The coherent data is then inversed Fourier transformed. This filtering narrows the elevation beam width associated with portions of each two-dimensional set of data. The filter varies as a function of the axial position of the coherent data.

Abstract: An ultrasound imaging system and ultrasound review station with a biophysical detector are provided. A biophysical attribute of a user is used to authorize (i.e., identify and authenticate) the user. Because the identification and authentication procedures are combined into a single step, the time and effort required for an authorized user to gain access to the ultrasound imaging system or ultrasound review station is greatly reduced. Using a biophysical attribute also makes the system or station practically impervious to impostors since biophysical attributes are unique and virtually impossible to duplicate. Also, since a user cannot forget or lose a biophysical attribute, the risk that an authorized user will be denied access is eliminated.

Abstract: An ultrasonic transmit waveform generator for an ultrasonic imaging system includes a waveform memory operative to store a plurality of stored ultrasonic waveforms, and an interpolator responsive to selected ones of the stored waveforms to form an ultrasonic transmit waveform.

Abstract: A diagnostic medical ultrasonic imaging method and system form first and second signals as a function of the Nth power of the absolute value of first and second ultrasound receive signals. These receive signals are associated with respective first and second transmit pulses that differ in phase and are both associated with overlapping or nearby regions of a subject. A combined signal is formed as a function of the difference between the first and second signals. The low pass component of the absolute value of this combined signal is then applied to an image processor. This low pass component, depending upon the value of N, can correspond to the second harmonic component of the combined receive signals, to the product of the fundamental and second harmonic components of the combined receive signals, and other combinations of fundamental and harmonic components.

Abstract: A system and method for tracking the position and orientation of a movable medical imaging device using a first and second sensor disposed on the device. The second sensor is of a different type than the first sensor and measures a P/O parameter different from that of the first sensor. The system and method also include techniques for recalibrating sensors using measurements from other sensors and improving the measurements made by some sensors using measurements from other sensors. The system and method also include measuring the position of a medical implement relative to a movable medical imaging device by providing a first and second subsystem on the medical implement and a third and fourth subsystem on the movable medical imaging device. The first subsystem has a sensor of a first type and the second subsystem has a sensor of a second type different from the sensor of the first type.