Abstract: A method for producing interpolated ultrasound images by storing at least two sequential ultrasound images and detecting the movement of objects of interest within two sequential images. A movement vector is then determined that describes the movement of each object within an image. One or more interpolated images are then produced by combining data from two sequential ultrasound images and the movement vectors. In addition, three-dimensional ultrasound images can be compensated for movement of a transducer or object of interest. At least two sequential ultrasound images are obtained and movement vectors are calculated for each object of interest. After determining the movement vectors, the images are compensated for the movement to realign the object of interest. The compensated images are then combined to produce three dimensional images.

Abstract: A radiation treatment apparatus (10) including a stand (12), a gantry (14) movably supported on the stand (12), the gantry (14) having a vertical section (16) and a generally linear cantilevered strut section (18), the cantilevered strut section (18) having a supported end adjacent the vertical section (16) and a projecting end opposite the supported end, a substantially linear particle accelerator (30) disposed within and longitudinally supported in generally parallel relationship with the cantilevered strut section (18), the accelerator (30) having a predetermined injection point (32) where particles are launched in the accelerator and a predetermined exit point (34) where the particles are discharged from the accelerator, a treatment head (22) coupled to the remote end of the cantilevered strut section proximate the exit point (34), the treatment head (22) for emitting a radiation beam (27), and a tuneable stiffening apparatus (40) attached to the accelerator (30) for substantially maintaining alignment be

Abstract: An ultrasonic transducer has a center row of transducers operating at a center row frequency and first and second outer rows of transducers operating at a common frequency or different frequencies lower than the center row frequency. In an enhancement of the ultrasonic transducer array, the center row of transducers has a matching layer with an acoustic velocity that is higher than matching layers that are associated with the first outer row and second outer row transducers. The matching layers can be selected such that the overall thickness of the transducer array is constant. A 1.5D ultrasonic transducer array operating at a higher center frequency and lower outer frequencies is adjustable to allow high resolution near field imaging in addition to better far field imaging without the need for a 2D transducer array.

Abstract: In a diagnostic ultrasound imaging system, a sequence of more than two signals is transmitted into the interrogation of the patient's body. In one embodiment of the invention, the pulses are grouped as pairs that have an inverted phase, that is, one is time-domain negative of the other. In an alternative of this embodiment, the pulses need not be paired, but rather are generated with alternating phase characteristics. The return signals are then filtered to isolate (or suppress) return signal components corresponding to portions of the interrogation region with non-linear (or linear) response characteristics. In a second embodiment of the invention, three or more pulses are generated so that have non-equidistant relative phase distribution. By combining the return signals, linear return signal components are suppressed.

Abstract: Method and system aspects for integrated automatic exposure control for portal imaging in radiotherapy are described. In an exemplary method aspect, the method includes controlling scanning and blanking of a target of a camera pick-up tube to capture an initial image, and analyzing the initial image to establish an initial image intensity. The method further includes utilizing the initial image intensity to determine a time for scanning a next image, and combining a scan of the next image with the initial image to produce a portal image with a maximized signal to noise ratio.

Abstract: A Doppler ultrasound clutter suppression system and method in which the clutter is first low-pass filtered (716) to suppress the flow component (4024) just before mean frequency estimation (718). The mean frequency is then estimated and mixed with the original clutter data which is positioned at DC. The low-pass filter bandwidth is predetermined based on the particular application and imaging parameters. The signal is then high-pass filtered (726) to remove the clutter component (4022).

Abstract: Method and system aspects for increasing resolution of a radiotherapy system to achieve virtual fractional monitor unit radiation delivery are described. Included in a method aspect, and system for achieving same, is identification of a desired treatment dose, the desired treatment dose exceeding a resolution of a radiation treatment device. Further included is the development of a schedule of treatment sessions for delivering the desired treatment dose by the radiation treatment device that produces a combined treatment dose equaling the desired treatment dose without exceeding the resolution within each treatment session.

Abstract: The present invention provides for delivering two one (1) centimeter by point five (0.5) centimeter intensity maps that are orthogonal to each other so as to generate microgradients within each one centimeter by one centimeter square. Thus, an effective intensity map grid size is point five centimeters by point five centimeters.

Abstract: A radiation therapy delivery and dosimetry error correction system. Rather than iteratively creating more segments to correct for dosimetry errors, the present invention receives the outputs from a segment optimization algorithm (i.e., a set of segments and an initial set of monitor units) and varies the number of monitor units associated with each segment to correct for dosimetry errors. Only if an extreme case exists will additional segments be added.

Abstract: A radiation therapy device (2) configured to receive a signal indicative of one or more of a patient's physiological parameters. The signal controls a gating, whereby a phase of an RF pulse (1002) and an injector pulse (1006) are varied so as to inhibit X-ray production without affecting injector or RF amplitudes.

Abstract: A method for increasing the valid data points produced by a digital filter. Input data is applied to a pair of filters that produce transients in response to different input data values. Output data from each of the filters is then combined to produce a data set with no transients. In one embodiment, the pair of filters have the same impulse response but the input data is applied to one filter in a first direction and to the other filter in an opposite direction. In another embodiment, the input data is applied to both filters in the same direction but the filters have inverted impulse responses. The present invention is particularly useful for minimizing a gap created when an ultrasound system alternates between different imaging modes. In addition, the present invention, can be used to increase the number of valid data points that are analyzed during color flow ultrasound imaging.

Abstract: A method of generating data compatible with forming a three-dimensional ultrasonic image includes selecting different frame rates for generating patterns of image information and frames of non-imaging information, such as motion information. The frame rates may be independently determined, based upon the desired characteristics of the two types of frames. Typically, image frames and motion frames are formed concurrently, with the formation of each motion frame overlapping the formation of more than one image frame, i.e., motion frames have a lower frame rate than image frames. After a sufficient number of image and motion frames have been generated, the image frames and the motion data are spatially coordinated to provide a three-dimensional flow image of a region of interest. In one approach, the spatial coordination of motion frames is implemented by incorporating the motion frames in a non-parallel relationship with the image frames.

Abstract: A fastener comprising first and second separable members, for engaging an elongate element. Each member includes first and second complementary shaped partial-cylindrical portions formed on a facing side thereof. The first and second partial-cylindrical portions of the first member have outside dimensions that are complementarily dimensioned with respect to the inside dimensions of the first and second partial-cylindrical portions of the second member, so that the first and second partial-cylindrical portions of the first member selectively engage and nest within the first and second partial-cylindrical portions of the second member when the facing side of the first and second members are positioned towards each other. The elongate element is engaged between the first and second members of the fastener by an engagement area formed when one of the first and second partial-cylindrical portions are nested.

Abstract: A system and method for radiation therapy delivery. A radiation therapy device according to the present invention is configured to monitor for instantaneous dose rate and accumulated dose even during conditions when the high voltage modulator is decoupled. If either the dose rate or the accumulated dose exceed a predetermined threshold, an interlock will be asserted to shut down the radiation treatment device.

Abstract: The present invention relates to a fast and accurate method for calculating fluence of a calculation plane over a patient. According to an embodiment of the present invention, only a subset of the collimator leaves are analyzed for the fluence calculation, thus reducing the number of calculations required. Additionally, pre-integrated values of scatter strips, associated with each point of the calculation plane, may be referenced in a lookup table. The use of these pre-integrated values allows the avoidance of adding the fluence contribution of each square on the scattering plane. Rather, pre-calculated values of a subset of the scattering plane (scatter strip) may be referenced and combined, thus reducing the number of calculations required for a final scatter contribution to a point on the calculation plane. Further, the thickness of the collimator leaves is considered in the fluence calculation, thus providing a more accurate model for the scatter contributions of points on the scattering plane.

Abstract: The present invention relates to a fast and accurate method for calculating fluence of a calculation plane over a patient. According to an embodiment of the present invention, only a subset of the collimator leaves are analyzed for the fluence calculation, thus reducing the number of calculations required. Additionally, pre-integrated values of scatter strips, associated with each point of the calculation plane, may be referenced in a lookup table. The use of these pre-integrated values allows the avoidance of adding the fluence contribution of each square on the scattering plane. Rather, pre-calculated values of a subset of the scattering plane (scatter strip) may be referenced and combined, thus reducing the number of calculations required for a final scatter contribution to a point on the calculation plane. Further, the thickness of the collimator leaves is considered in the fluence calculation, thus providing a more accurate model for the scatter contributions of points on the scattering plane.

Abstract: A robust histogram analysis algorithm is used in accordance with the present invention to control the electronic portal image analog to digital (A/D) window such that the acquired images will have sufficient contrast for their uses in radiotherapy. The algorithm includes setting an initial estimate of a region of interest within a histogram, the histogram including pixel counts and pixel values related to the pixel counts, and determining two dominant peaks inside the region of interest. One of the two dominant peaks is below a predetermined value and the other of the two dominant peaks is between the predetermined value and a second predetermined value. If the one dominant peak is more than two times the standard deviation of the other dominant peak, then a first local minimum to the right of the one dominant peak will be the revised boundary.

Abstract: An ultrasound front end circuit (1000) according to the present invention includes a single transformer core which performs all of the pulse and transmit/receive switching functions. A transmit pulser (1102) is formed by a pair of transistor switches in combination with a transformer having first windings (N1, N2) driven by a DC source. A secondary winding (N3) provides a voltage step up for transmitted wave forms and a pair of anti-parallel shunt diodes (1014) on the receiver terminal direct the transmitted 0 waveform to the ultrasound transducer (1024). A floating third winding (N4) shunted by a current biased diode bridge (1002) provides an effective open circuit across the secondary winding while transmitting high amplitude signals. The third winding (N4) and diode bridge (1002) act to short circuit the secondary winding (N3) while receiving small amplitude signals, thus providing a direct connection between the transducer (1024) and receiver (1020).

Abstract: An amplifier (32) is provided which allows for reduced system power dissipation. The amplifier (32) can dynamically draw power from different supply voltages in response to an input voltage signal. The amplifier (32) includes a plurality of complementary transistor pairs (40-46), where each transistor pair is coupled to a respective power supply. Each transistor pair provides output current when the input voltage signal is within a respective predetermined voltage range. This arrangement permits the amplifier (30) to interpolate between the supply voltages to generate a continuous amp output. System power is conserved by selecting the power supply which can most efficiently supply the required current within the voltage range.

Abstract: A transmit/receive circuit employing passive elements. A transmit/receive circuit according to an embodiment of the present invention includes a transformer having a primary winding coupled to an input stage and an output stage. A transducer is coupled to the secondary winding of the transformer. A diode limiter is coupled to the input stage and a diode bridge is coupled to a node at the output stage. The input and output stages are alternatingly grounded. An output switch including an inverse parallel circuit of two diodes having opposite polarities may be connected at the output stage between a transmitter and the transformer. Alternatively, a complementary common emitter amplifier may be provided at the output stage. The circuit thus electrically couples the transducer element to the receiver during reception and electrically decouples both the transducer and the transmitter from the receiver during transmission.