Abstract: The preferred embodiments described herein provide a medical diagnostic ultrasound imaging system with an ambient room light. The medical diagnostic ultrasound imaging system comprises a transducer probe, a beamformer, a processor, and a display device. In one preferred embodiment, an ambient room light is integrated with the display device of the ultrasound system. In another preferred embodiment, the ambient room light is carried by or integrated with an ultrasound imaging system cart that carries some or all of the components of the ultrasound system. Other preferred embodiments are provided, and each of these preferred embodiments can be used alone or in combination with one another.

Abstract: Methods and systems for providing consistent power and reducing power consumption for an ultrasound system are provided. The ultrasound system is provided with an uninterruptable power supply. Power is provided from an outlet through the uninterruptable power supply to the ultrasound scanner. If the power from the outlet falls below a threshold is of an insufficient quality or is otherwise unavailable, the uninterruptable power supply provides power. For mobility, the uninterruptable power supply provides power, avoiding the need to plug the ultrasound system into an outlet. To reduce the drain on the uninterruptable power supply or other source of power, the ultrasound system includes power reduction systems and methods. One or more electrical components, subsystems or the entire ultrasound system is operated in a reduced power state while not in use. For example, some digital electrical components draw more power in response to clock signal triggers.

Abstract: The preferred embodiments described herein provide a medical diagnostic ultrasound catheter with a tip portion carrying an ultrasound transducer. The tip portion comprises a first portion that is in the acoustic path of the ultrasound transducer, and a second portion that is outside the acoustic path of the ultrasound transducer. The first and second portions comprise different acoustic and mechanical properties. For example, the mechanical properties of the second portion can give the catheter tip sufficient durability to withstand normal use without bowing, while the acoustic properties of the first portion can give the catheter tip desired acoustic properties. This may be especially important for small diameter catheters (e.g., maximum cross-sectional dimensions less than or equal to about 10 French or 8 French) where the stiffness of the catheter tip is reduced.

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: A medical ultrasonic imaging system uses an adaptive multi-dimensional back-end mapping stage to eliminate loss of information in the back-end, minimize any back-end quantization noise, reduce or eliminate electronic noise, and map the local average of soft tissue to a target display value throughout the image. The system uses spatial variance to identify regions of the image corresponding substantially to soft tissue and a noise frame acquired with the transmitters turned off to determine the mean system noise level. The system then uses the mean noise level and the identified regions of soft tissue to both locally and adaptively set various back-end mapping stages, including the gain and dynamic range.

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 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 ultrasonic imaging system carries a holder that supports a gel container in an inverted position. The gel container includes a metallic cap including a heat exchanger in good thermal contact with the gel of the container, and the holder includes a heating element in good thermal contact with the cap. When the ultrasound system is powered, power is automatically applied to the heating element of the holder, thereby heating ultrasound coupling gel in the container near the spout.

Abstract: A two level power supply and method are provided for ultrasound transmission. A coupling capacitor is provided between a high voltage source and a low voltage source. The coupling capacitor provides direct current restoration for a two level power supply selector connected with an ultrasound transmit array. For example, a clamping circuit, including a capacitor and a diode, is provided between the high voltage and the low voltage sources. The high voltage source connects as a power supply to a pulser. Control signals are provided to the pulser to switch the output between the high voltage and ground depending on the type of ultrasound signal being transmitted. A voltage rail of the transmit array connects with the clamp circuit and receives a low voltage for CW Doppler mode imaging and a high voltage for B-mode imaging. This low cost circuitry may simplify and improve the delivery of high voltage in a two or more level power supply selection in ultrasound imaging.

Abstract: A method and system for reducing speckle for two and three-dimensional images is disclosed. For two-dimensional imaging, a one and a half or a two-dimensional transducer is used to obtain sequential, parallel or related frames of elevation spaced data. The frames are compounded to derive a two-dimensional image. For three-dimensional imaging, various pluralities of two-dimensional frames of data spaced in elevation are compounded into one plurality of spaced two-dimensional frames of data. The frames of data are then used to derive a three dimensional set of data, such as by interpolation. Alternatively, the various pluralities are used to derive a three-dimensional set of data. An anisotropic filter is applied to the set of data. The anisotropic filter filters at least along the elevation dimension. In either situation, various displays may be generated from the final three-dimensional set of data. A method and system for adjustably generating two and three-dimensional representations is also disclosed.

Abstract: A portable medical diagnostic ultrasound system is provided which includes shielding for electromagnetic interference by forming shielded enclosed compartments around the individual components of the ultrasound system. This compartmentalization of components isolates EMI between the components themselves as well as the outside world. Further, the EMI shielding provides structural rigidity and support for the entire ultrasound system. In another aspect, the EMI shielding provides heat dissipation capability for the internal components of the ultrasound system. The portable medical diagnostic ultrasound system further provides a transducer connector which provides high density interconnects between the transducer and the ultrasound system while providing an ergonomically easy to handle connector. Further, the connector is rugged, providing a high number of connection and disconnection cycles.

Abstract: A capacitive microelectromechanical ultrasound transducer array with improved efficiency and durability is provided. Efficiency is provided by stacking CMUTs in the range dimension (i.e. away from the face of the transducer). A plurality of chambers and associated membranes are stacked along a range dimension or parallel to the direction of acoustic radiation. Because the CMUT transducer element is stacked, ultrasound is transmitted through the plurality of chambers, amplifying the response of the transducer element. Durability is increased within the transducer by filling the chamber with a nongaseous filler. A liquid, polymer, solid or plasma fills the chamber or chambers. The nongaseous filler allows movement of the membrane for transducing between acoustic and electrical energies, but prevents collapse or bottoming out of the membrane.

Abstract: A medical diagnostic ultrasonic imaging system acquires image data for at least two frames at each of multiple positions, each frame identified with a respective phase of a physiological cycle. A multiphase 3-D or extended field of view data set is constructed from the image data. Then a plurality of images are generated from the multiphase data set. Each image is associated with a respective phase of the physiological cycle, and these images are displayed in sequence to a user. The acquired sequence of image frames is synchronized by adding frames to the sequence in portions of the sequence characterized by a low number of image frames per period of the physiological cycle, and by removing image frames from portions of the sequence characterized by an excessive number of frames per period of the physiological cycle.

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. Using variations in characteristics for each component frame or sub-set of data, the extended field of view image is enhanced. For example, the steering angle or acquisition frequency associated with each component image is different.

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: A pulse echo beamforming system generates high spatial bandwidth ultrasound images using only a few transmit/receive events per frame. Each transmit/receive event consists of firing an unfocused or weakly focused wave and receiving and storing the echo on every receive channel. Each set of stored echoes is delayed and apodized to form component beams for each desired image point in the region insonified by that particular wave. The final images are synthesized by adding two or more of the component beams for each image point.

Abstract: Line synthesis avoids artifacts from differences in collateral destruction of contrast agent. Data representing a plurality of scan lines is received in response to each transmit event. Transmission and reception along the same scan lines are repeated a plurality of times for loss correlation imaging. Coherent data or data prior to detection along two or more scan lines is combined, removing differences. The combined data represents a synthesized line of data for detection. Line data representing contrast agents or not representing contrast agents may be synthesized from detected data. Detected data or data in the magnitude and phase domain representing two or more scan lines is combined. By altering the data provided to a flow processor or Doppler data detector, the relative phase of the data representing the two scan lines is determined. A magnitude for a synthetic line is calculated as a function of the magnitude of data representing two separate scan lines and the relative phase.

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: A medical diagnostic ultrasonic imaging system analyzes receive signals generated by the system to adaptively set the interline delay and/or the transmit power to optimize frame rate while reducing or eliminating the wraparound artifact associated with transmit events that are too closely spaced in time for currently prevailing imaging conditions.

Abstract: A digital-to-analog converter that outputs positive and negative portions of the desired bi-polar waveform as a representative unipolar waveform (e.g. absolute value of the bi-polar waveform) is connected to a switch. The switch selects between current driver paths as a function of the positive or negative polarity of the desired bi-polar waveform. The current drivers feed a push-pull output amplifier to generate the bi-polar ultrasound waveform. Alternatively, a digital-to-analog converter with differential outputs is connected to two difference amplifiers. The difference amplifiers provide current signals to the push-pull output amplifier through their supply nodes. A single scaling resistor connects between the conventional outputs of two differential amplifiers to reduce mismatching between the positive and negative waveform paths. As a result of the feedback between the two difference amplifiers, a lower level of even harmonic distortion products is achieved.

Abstract: A medical imaging system provides increased detectability of targets such as membranes, tendons, muscle fibers and biopsy needles that have strong directional responses. This improved result is achieved by compounding multiple images generated by using only one or two transducer firings per ultrasound line. Speckle variance is also reduced as the result of spatial compounding, and this reduction improves the detectability of soft-tissue lesions.