Abstract: An image formed from compounded frames of ultrasound data acquired with different steering angles is displayed. Each component frame is associated with a scan of the entire displayed region. A majority of scan lines for each component frame are pointed in one direction or the same relative direction, and a minority of the scan lines are steered at different angles within each component frame to scan the rest of the display region, but with a different steering angle for the majority of scan lines of each of the component frames. As a result, the benefits of spatial compounding component frames associated with different steering angles are provided without having to apply filtering to reduce line artifacts.

Abstract: A noise-adaptive method for processing an ultrasonic image set forms a filtered image set having a selectively enhanced noise component as compared to the original image set. A noise parameter is generated as a function of the image set and the filtered image set, and then the noise parameter is used in ultrasonic image processing. A background noise image is generated from the noise parameter and the original image and is used in ultrasonic image processing.

Abstract: A medical ultrasound imaging pulse transmission method transmits at least three pulses, including at least two pulses of different amplitude and at least two pulses of differing phase. The larger-amplitude pulse is transmitted with a larger aperture and the smaller-amplitude pulses are transmitted with respective smaller subapertures. The subapertures are arranged such that the sum of the subapertures used for the smaller-amplitude pulses is equal to the aperture used for the larger-amplitude pulse. In this way, pulses of differing amplitudes are obtained without varying the power level of individual transducer elements, and precise control over pulse amplitude is provided.

Abstract: The gain for multiple mode imaging and/or contrast agent imaging is automatically adjusted. The gain algorithm separately determines gain parameters for two different types of imaging, such as tissue and contrast agent imaging. The gain based on the contrast agent image may be optimized to provide maximum sensitivity, such as by mapping noise values measured prior to injection of contrast agent to low values within the dynamic range or somewhat below the display dynamic range. The automatic gain based on the contrast agent image may be free of variance calculations. One of the two gain parameters is selected as the system gain, or the two gain parameters are combined to form the system gain. The presence of contrast agents within the image may be determined, and different gain parameters used based on the presence or absence of contrast agents. Various ones or combinations of the gain adjustments summarized above may be used.

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: Two or more temporal indicators are used for interleaving frames from a plurality of physiological cycles. For example, frames of one cycle are separated from the frames of another cycle based on an ECG signal. Data representing an imaged region for each of the frames is then used for temporally aligning the frames. For example, average velocity waveforms calculated from the frames of each of the cycles are fitted together. The temporal position of each of the frames within a base physiological cycle is determined based on the fitting. The interleaved frames provide a higher effective frame rate with improved temporal resolution which is based on the accurate interleaving of the data from the plurality of physiological cycles. Course alignment is provided using one event or temporal indicator. A more refined temporal alignment is provided in response to a second temporal indicator.

Abstract: A medical diagnostic ultrasonic imaging system includes a transmit waveform generator that uses stored parameters to completely define an arbitrarily complex transmit waveform. Preferably, the stored parameters define an envelope function and a modulation function in a piecewise fashion using a number of sets of quadratic parameters. These quadratic parameters are used to calculate the desired envelope function and modulation function in the log domain, and the envelope and modulation functions are combined in the log domain and then converted to the linear domain. Multiple separate transmit waveforms may be combined in a single channel, and individual channels may be combined prior to application to the transducer elements.

Abstract: Multiple layer elements for a transducer array are provided. Each element comprises two or more layers of transducer material. Various of the elements include one or more of: (1) multiple-layer, multiple-dimensional arrays where the layers are electrically connected through asperity contact, (2) multiple layer array of elements where air or gas separates at least two elements, (3) an even number of layers polymerically bonded together where each layer is electrically connected through asperity contact, (4) multiple-layers where each layer comprises transducer material and electrodes in a substantially same configuration, and (5) electrically isolating electrodes on layers by kerfing or cutting after bonding the layers together.

Abstract: An ultrasound image is morphed for perfusion assessment. Various images within a sequence of images or movie clip are mapped to one frame of reference using local warping. Nonlinear local image transformations or other warping based on local estimates of motion are used to interpolate different images to the common reference. The elastic stretching and compression of local image data results in a sequence of images where the same spatial location in each image represents the substantially same spatial location of the imaged tissue. The organ, tissue or region of interest is stationary throughout the sequence of images.

Abstract: A method and system for contrast agent imaging with a catheter transducer is provided. The catheter transducer may comprise an intra-vascular, intra-cardiac or other transducer for insertion into or through a small space. The catheter transducer is inserted within the heart or other portion of a patient. Contrast agents, such as micro-spheres, are injected into the patient. Using the catheter transducer, ultrasonic acoustic energy is transmitted, and reflected energy is received. The reflected energy is responsive to the contrast agents. An image processor generates an image of the tissue and contrast agents as a function of the reflected energy. The image provides an indication of perfusion. Alternatively, the ultrasound system calculates perfusion. By generating intra-vascular images or data, interference from other tissues is avoided. Therefore, the perfusion information obtained may have higher resolution. Images with better resolution better assist doctors in medical diagnosis.

Abstract: A medical diagnostic ultrasound imaging system aligns substantially co-planar two-dimensional images to form an extended field of view using improved compounding methods. Compounding with a finite impulse response is used for more versatile compositing. The compounding is adaptive, such as through adapting the image regions, weighting, or type of compounding as a function of correlation, location within the image, estimated motion or combinations thereof. A user warning is provided as a function of the correlation between images.

Abstract: Methods and systems for detecting contrast agents is provided. Differences between different sized vessels throughout a period of contrast agent enhancement are identified without significantly depleting the available contrast agent. Dual detection paths are used for imaging, such as one path for detecting nonlinear response and another path for detecting differences between the responses to two or more pulses. Where echoes from two or more pulses of acoustic energy are combined to detect the nonlinear response, the nonlinear response may also include signals originating from a loss-of-correlation (LOC) or motion between received pulses. These signals generated from LOC or motion can be produced from agent disruption where a second received echo is different from a first received echo due to a change in a bubble's shape (i.e., destruction), or from simple spatial translation between acoustic pulses as seen from the same spatial location, respectively.

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 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: A system and method of processing received signals in an ultrasound imaging system is disclosed. In the system, the received signals are amplified by means of a gain controlled amplifier, and the gain of the amplifier is varied, by varying the load capacitance, as a function of depth (time) to compensate for the attenuation of ultrasonic energy at different depths within a patient's body.

Abstract: Accurate tissue motion systems and methods are provided. Motion of the ultrasound transducer is accounted for in estimates at tissue motion. Correcting for transducer motion better isolates localized tissue contractions or expansions, such as motion of the myocardial muscle or fibers. Accurate motion estimation is also provided by determining an angle of motion from the ultrasound data. The angle of motion is used to adjust velocity estimates, providing two-dimensional velocity vectors (i.e. motion estimates comprising motion in at least two dimensions). Movement of tissue is determined by correlating speckle or a feature represented by two different sets of ultrasound data obtained at different times. Additional aspects include tracking the location of a tissue of interest. A characteristic of strain, such as the strain rate or strain, is calculated for the tracked tissue of interest.

Abstract: A method and system for indicating the position and orientation of a scan plane relative to a patient is provided. The image as presented on a display is oriented in accordance with the orientation of a transducer. The orientation may provide for displaying an image where the transducer is not in a transducer up or transducer down position, but is rotated away from vertical of the display. Alternatively or additionally, a two or three-dimensional graphical generic representation is provided with a scan plane indicated as a polygon or image rendering within a generic representation to show relative positioning of the scan plane with respect to the patient.

Abstract: The use of any micro-mechanical component in an ultrasound system is disclosed. In particular, the use of micro-relays, micro-switches and inductors in the transducer probe head, in the transducer connector, coupled with the system transducer connector(s) or anywhere else in the system. In an ultrasound system, micro-mechanical components such as micro-fabricated switches, relays and inductors permit impressive size reduction, cost reduction, signal-integrity enhancement and improved operational flexibility.

Abstract: A medical ultrasound imaging pulse transmission method transmits at least three pulses, including at least two pulses of different amplitude and at least two pulses of differing phase. The larger-amplitude pulse is transmitted with a larger aperture and the smaller-amplitude pulses are transmitted with respective smaller subapertures. The subapertures are arranged such that the sum of the subapertures used for the smaller-amplitude pulses is equal to the aperture used for the larger-amplitude pulse. In this way, pulses of differing amplitudes are obtained without varying the power level of individual transducer elements, and precise control over pulse amplitude is provided.

Abstract: The preferred embodiments described herein provide a medical diagnostic ultrasound imaging system and method for constructing a composite ultrasound image. In one preferred embodiment, visual and audio components of an ultrasound image are separately stored so that a composite image including some or all of the components can later be constructed. The audio component can take the form of Doppler audio or voice data, for example. In another preferred embodiment, stored computer-readable program code is selected to perform an operation on a constructed composite ultrasound image.