Abstract: A method and an apparatus for increasing the spatial resolution and sensitivity of a color flow image while maintaining a desired acoustic frame rate. The ultrasound energy is concentrated at a more narrowly defined focal region, which allows for increased flow sensitivity and vessel filling. Better flow uniformity across the color region of interest is also achieved. The method uses multiple transmit focal zones, and transmit and receive apertures having low f-numbers. Using multiple focal zones with low f-numbers allows for tight focusing over a larger depth-of-field. Unique waveforms and unique gain curves are used for each focal zone. Each focal zone is fired on a separate acoustic frame. An adaptive frame averaging algorithm is used to blend together the in-focus data from each of these acoustic frames before the data is displayed.

Abstract: A method and an apparatus for mitigating aliasing when imaging moving fluid or tissue using velocity Doppler shift data. To eliminate the effects of slight aliasing in the velocity mode, symmetrical (or non-directional) velocity/color maps are used to map positive and negative velocity data of the same magnitude to the same color and same display intensity. If the pulse repetition frequency is adjusted so that only subtle aliasing is present, an optimal frame averaging of the data can be achieved by removing the sign of the velocity data either before or during frame averaging.

Abstract: A method and an apparatus for three-dimensional imaging of ultrasound data by constructing projections of data from a volume of interest. An ultrasound scanner collects B-mode or color flow images in a cine memory, i.e., for a multiplicity of slices. A multi-row transducer array having a uniform elevation beamwidth is used to provide reduced slice thickness. The data from a respective region of interest for each of a multiplicity of stored slices is sent to a master controller, such data forming a volume of interest. The master controller performs an algorithm that projects the data in the volume of interest onto a plurality of rotated image planes using a ray-casting technique. The data for each projection is stored in a separate frame in the cine memory. These reconstructed frames are then displayed selectively by the system operator. Segmentation of three-dimensional projection images is enhanced by decreasing the thickness and increasing the resolution (i.e.

Abstract: A method for optimizing the beam distribution to obtain the highest frame rate together with the least amount of acoustic noise while limiting the spatial aliasing to an acceptable level. The beam distribution is adjusted according to the scan format and as a function of the beam width, which is proportional to the product of the F number and the operating wavelength. As the F number changes in going from the shallow depth to a deeper depth, the number of beams fired to construct an image would change correspondingly. In addition, if the F number is changing in going from the center of image to the edge of the image, the separation of the fired beams would change. Alternatively, if the operating frequency is being changed in going from shallower depths to deeper depths or in going from the center of image to the edge of the image, the beam spacing is changed in order to fire the optimum number of beams at all times, and thereby obtain the highest frame rate.

Abstract: In a method for maximizing frame rate of an ultrasound imaging apparatus, ultrasound B and color mode vector density are reduced. Initially, an actual displayed image size is determined. A minimum vector density requirement is then determined for B which will provide a useful image based on the actual displayed image size. The number of vectors in the image is then adjusted to meet the minimum vector density requirement.

Abstract: A method and an apparatus for activating one of a plurality of connected transducers in response to the operator picking up that transducer. This enables the selection of a transducer without the need for pressing a button or key. Automatic selection is accomplished by placing a proximity sensor located within the holder of the transducer or on the transducer itself to indicate whether the transducer is being held by its holder. Switches are also incorporated to detect when a transducer connector has been plugged into each port on the ultrasound imaging machine. Depending on the order in which unactivated normal transducers attain a state whereby the respective normal transducer is both connected and out of its holder, a stack of probe identifiers is created. Identifiers for connected special transducers are added to the stack below any probe identifiers for normal transducers. The identifier at the top of the stack indicates the transducer which will be activated next, i.e.

Abstract: A dynamic firing sequence for ultrasound imaging apparatus can be achieved in accordance with the present invention. Initially, operator selected parameters are provided and predetermined system constants are stored. The operator selected parameters in B mode include imaging depth. The operator selected parameters in Doppler mode include velocity scale, doppler range gate position and Doppler range gate size. The operator selected parameters in color mode include velocity scale and region of interest depth. PRI and minimum vector time are calculated using the operator selected parameters and the predetermined system constants. These calculations are used to maximize interleaving, thereby maximizing frame rate.

Abstract: In a method for obtaining temporal equity of multiple images for ultrasound imaging equipment, a vector set is determined for each of the multiple images, representative of vectors to be aligned. A plurality of independent weights is then calculated for each image based on the vector sets. The plurality of calculated independent weights is used to determine a firing sequence which provides temporal equity of the multiple images.