Abstract: A variable self-compensating detent control system for improved positioning accuracy and repeatability is provided. The detent control system provides a system for reducing positioning errors in the positioning of an X-Ray tube in an X-Ray imaging system, such as accurate and repeatable positioning of the X-Ray tube at detents. The control system preferably includes a sensor unit generating positional or velocity signals indicative of the position or velocity of the X-Ray tube and a microprocessor receiving the positional signals and determining an overshoot correction. The overshoot correction is used by the X-Ray system to control a locking system controlling the position of the X-Ray tube. The sensor unit may employ a potentiometer, a digital encoder, or preferably both in combination to determine the positional or velocity signals.

Abstract: An ultrasound system and method for calculation and display of tissue deformation parameters are disclosed. An ultrasound acquisition technique that allows a high frame rate in tissue velocity imaging or stain rate imaging is employed. The tissue deformation parameter strain is determined by an accumulation of stain rate estimates for consecutive frames over an interval. The interval may be a triggered interval generated by, for example, an R-wave in an ECG trace. The strain calculation may be improved by moving the sample volume from which the stain rate is accumulated from frame-to-frame according to the relative displacement of the tissue within the original sample volume. The relative displacement of the tissue is defined by the instantaneous tissue velocity of the sample volume. An estimation of strain rate based upon a spatial derivative of tissue velocity is improved by adaptively varying the spatial offset, dr. The spatial offset, dr, can be maximized to cover the entire tissue segment (e.g.

Abstract: A system and method for acquiring ultrasound information at an acquisition rate and displaying at least a portion of the acquired ultrasound information at a display rate that is slower than the acquisition rate is disclosed. Ultrasound information may be continuously acquired and stored at a frame-rate that is greater than the perception rate of the human eye. At least a portion of the acquired ultrasound information is displayed at a frame-rate that allows human perception. Acquisition and display are synchronized from time-to-time upon satisfaction of a synchronization condition. The synchronization condition may be related to a predetermined time interval or a triggering event generated by or through triggering generated by, for example, a physiological event detected in, for example, an ECG trace.

Abstract: A distributed medical diagnostic system is implemented using one or more first computers that execute one or more instances of a first medical diagnostic system software module and one or more second computers that execute one or more instances of a second medical diagnostic system software module. The first and second medical diagnostic system software modules are members of a system software set (including any number of such system software modules) that implements any chosen medical diagnostic system. One or more communication links are present to provide communication between the system software modules that exchange data.

Abstract: A method for multi-angle compound flow imaging includes the steps of receiving first and second (in general, N) ultrasound signal reflections from a target. Each ultrasound signal reflection is preferably oriented at a different angle. The method further includes evaluating a display decision algorithm based on the ultrasound signals to determine a display result and displaying the display result, for example, as an angiogram. An ultrasound medical diagnostic imaging device includes an ultrasound transducer for receiving a first and second (in general, N) ultrasound signal reflections from a target. Each ultrasound signal reflection is preferably oriented at a different angle. The device further includes a processor coupled to the ultrasound transducer for evaluating a display decision algorithm based on the ultrasound signals to determine a display result. A display coupled to the processor shows the display results, for example, as an angiogram.

Abstract: A method for determining a suggested value for a cancellation parameter for a dual energy decomposition includes obtaining a first energy level image of internal structure, obtaining a second, lower, energy level image of the internal structure, and iteratively processing the images to determine a provisional value for the cancellation parameter. The iteration includes varying a cancellation parameter in a cancellation equation, obtaining a structure cancelled image from the first and second energy level images according to the cancellation equation, and evaluating a cancellation metric from the structure cancelled image. The provisional cancellation parameter may then be chosen (e.g., as the value that approximately minimizes a variance cancellation metric). Further iterations may be performed around the provisional cancellation parameter to refine the provisional cancellation parameter into a final cancellation parameter.

Abstract: A preferred embodiment of the present invention provides a method and apparatus for reducing photoconductive effects in dual energy applications of solid state digital x-ray detectors. The method comprises exposing a detector to a first exposure from an energy source and obtaining a first image data set during a first read time from the first exposure following a first delay. The method further comprises exposing the detector to a second exposure from the energy source and obtaining a second image data set during a second read time from the second exposure following a second delay. The first delay is less than the second delay. The first read time is less than the second read time.

Abstract: A system an method for determining the Dose Area Product (DAP) in an X-ray imaging system is provided. The present system constructs a pre-determined parameter space describing the DAP contour over ranges of typical imaging parameters. Later, when the employed in clinical imaging, a DAP processor on board the imaging system received a set of the imaging parameters being employed. The DAP applies the set of parameters to the parameter space to interpolate the DAP being delivered by the clinical imaging system. The present system may be individually calibrated to a specific X-ray imaging system to provide more optimal DAP values. Additionally, in imaging system employing an asymmetric shutter, such as a one-leaf shutter, the present system may determine a rotational scale factor for the DAP based on the rotation of the shutter. The rotational scale factor may also be calibrated to an individual X-ray imaging system.

Abstract: An ultrasound system determines the relative movement in a first direction (F1) of first matter, such as blood flow, and second matter, such as an artery wall, in a subject under study (S). A beam (B1) of ultrasound waves defining a plurality of beam positions (BP1 and BP2) and beam axes (A1and A2) are moved in scan directions having components parallel to direction F1. First and second blocks of data representing the first and second matter, respectively, are generated. A processor (20) performs an estimation of speckle size on first data to obtain a first result, and performs analysis of the second block of data to obtain a second result. The two results are analyzed to obtain a measure of the relative movement of the first and second matter.

Abstract: An ultrasound survey frame (SF) is processed in order to determine the portions representing fluid flow. An assembly (20) again rescans only the portions of a subject represented by the portions of the survey frame in which fluid flow was found. Target frames (TF) then are created from the rescanning and are processed in order to provide a color flow image restricted to the portions of the survey frame in which fluid flow is indicated.

Abstract: A radiographic imaging system including a solid state x-ray imager is disclosed. An x-ray tube is supported in a vertical x-ray tube support system alternately or in addition to a overhead angulating x-ray tube support system. A solid state x-ray imager is supported in a wall stand alternately or in addition to an angulating table stand. Associated sensors sense the position of the solid state x-ray imager, and a position controller adjusts the position of the x-ray tube such that the x-ray tube is positioned at the center of the solid state x-ray imager. Readout circuitry receives the analog image from the solid state x-ray imager and transmits the corresponding digital information to a digital processor for image creation or manipulation. The digital image may than be displayed on a digital imager acquisition and display system.