Abstract: A Multiple Aperture Ultrasound Imaging (MAUI) probe or transducer is uniquely capable of simultaneous imaging of a region of interest from separate apertures of ultrasound arrays. Some embodiments provide systems and methods for designing, building and using ultrasound probes having continuous arrays of ultrasound transducers which may have a substantially continuous concave curved shape in two or three dimensions (i.e., concave relative to an object to be imaged). Other embodiments herein provide systems and methods for designing, building and using ultrasound imaging probes having other unique configurations, such as adjustable probes and probes with variable configurations.

Abstract: Changes in tissue stiffness have long been associated with disease. Systems and methods for determining the stiffness of tissues using ultrasonography may include a device for inducing a propagating shear wave in tissue and tracking the speed of propagation, which is directly related to tissue stiffness and density. The speed of a propagating shear wave may be detected by imaging a tissue at a high frame rate and detecting the propagating wave as a perturbance in successive image frames relative to a baseline image of the tissue in an undisturbed state. In some embodiments, sufficiently high frame rates may be achieved by using a ping-based ultrasound imaging technique in which unfocused omni-directional pings are transmitted (in an imaging plane or in a hemisphere) into a region of interest. Receiving echoes of the omnidirectional pings with multiple receive apertures allows for substantially improved lateral resolution.

Abstract: A method of full-field or “ping-based” Doppler ultrasound imaging allows for detection of Doppler signals indicating moving reflectors at any point in an imaging field without the need to predefine range gates. In various embodiments, such whole-field Doppler imaging methods may include transmitting a Doppler ping from a transmit aperture, receiving echoes of the Doppler ping with one or more separate receive apertures, detecting Doppler signals and determining the speed of moving reflectors. In some embodiments, the system also provides the ability to determine the direction of motion by solving a set of simultaneous equations based on echo data received by multiple receive apertures.

Abstract: A turbine vane adjustment assembly for calibrating the nozzle/throat width dimension between adjacent adjustable vanes in a nozzle vane ring assembly and for producing conjoint rotation of the individual vane following their calibration includes a vane stem that extends outwardly of a turbine case and further includes a motion converting sleeve in surrounding relationship thereto and coacting means between the sleeve and the vane stem that concurrently rotates both the sleeve and the stem and also provides relative axial movement of the sleeve with respect to the vane stem; the adjustment assembly further includes an actuator arm for rotating each of the vanes and means for connecting the actuator arm to the sleeve to cause angular positioning of the actuator arm to be directly transmitted to each of the vanes following calibration thereof.