Abstract: In a patient monitoring system which includes a signal transmission path between that portion of the patient monitoring system which acquires the physiological signals and that portion of the system which processes and displays the acquired signals, a method and apparatus is provided for displaying to a user of the system a time delay that is associated with a delay of the display of the physiological signals.

Abstract: Telemetry transmitting apparatus and a method are provided for reception and transmission of heart related electrical signals, such as electrocardiogram (EKG) and/or cardiac pacemaker signals, from a plurality of electrodes coupled to the body of a medical patient. A receiving facility of the apparatus receives a plurality of analog signals representing at least the EKG signals. An output signal representing the EKG signals is formed and transmitted, via a wireless coupling, to a telemetry receiver. An analog output port is provided on the telemetry transmitting apparatus. The analog output port is also coupled to the receiving facility. A plurality of output signals representing the EKG signals is provided to the analog output port of the telemetry transmitting apparatus. The analog output port may be coupled to buffers at the input terminals of the apparatus.

Abstract: A three-dimensional gadolinium-enhanced MR study of e.g. the patient's thoracic vasculature is carried out while the patient holds his or her breath. Acquisition of all data in each three-dimensional partition takes place during one and only one heartbeat. By synchronizing the MR pulse sequence to the patient's cardiac cycle, and advantageously by acquiring the MR data during the diastolic phase of the cardiac cycle, image artifacts caused by cardiac motion and pulsatile flow are eliminated or minimized.

Abstract: A monitor system for acquiring medical data from a plurality of sensors adapted for coupling to a patient located in a given patient monitoring area. The system comprises a portable monitor, a peripheral device, and a docking station. The portable monitor is adapted to be coupled to the plurality of sensors for receiving, processing and displaying patient data signals acquired from the plurality of sensors The peripheral device requires connection to the monitoring system, and comprises, i.e., a strip chart recorder. The docking station is located within the given patient monitoring area and includes at least first and second docking station platforms adapted for being selectively coupled to the portable monitor and the peripheral device respectively, for providing data transfer between the peripheral device and the portable monitor while the portable monitor acquires medical data from the patient.

Abstract: An apparatus for monitoring the respirations of a patient includes a device for generating a respiration signal having amplitude modulations representative of patient respirations, as well as respiration artifacts, and a processor coupled to the respiration signal generating device and responsive to the respiration signal for 1) detecting inflection points in the respiration signal; 2) determining if either one of a portion of the respiration signal which precedes or follows each detected inflection point has a slope which exceeds a predetermined slope threshold level which is indicative of a respiration artifact; and 3) developing breath indication information based upon the slope threshold determination.

Abstract: A method of establishing coincidence between a field size of a light field used in a setup mode of a radiation system and a field size of a radiation field used in an operation mode of the system includes providing automatic adjustment of field-defining structure to compensate for differences in optical properties of the light and the radiation. A light beam passing through the field-defining structure typically exhibits greater scattering than an X-ray beam passing through the structure. For each of a number of different settings of the field-defining structure, the difference between the field sizes of the light and the radiation are determined and recorded. Then, for a particular desired field size, the field-defining structure can be automatically adjusted to provide compensation.

Abstract: A method for compensating for inoperative transducer elements in an ultrasound transducer. The transmit voltage of the driving signals applied to transducer elements that are adjacent an inoperative element is increased to compensate for the inoperative element. Preferably, a linear interpolation used whereby the power/gain of the signals to be applied to the inoperative element is divided equally among the adjacent operative elements. If an inoperative transducer element is adjacent more than one inoperative element, then the gain of the operative transducer element is increased accordingly for each such inoperative element. In addition, the gain of the echo signals produced by the adjacent transducer elements is increased to compete for the inoperative element.

Abstract: A Doppler audio dealiasing system has a zero inserter that inserts zeros between input samples of signal. The resultant signal is then processed in various ways. After the zeros are inserted and a new signal is formed, the newly formed signal is filtered with or without a modulator and otherwise processed to remove inappropriate parts to generate forward and reverse audio signals corresponding to the adjuster.

Abstract: A probe holder embodies an insert body removably set into a through-slot of an ultrasound system panel. The holder defines an inner cavity extending from a first opening at a top surface to a second opening at a bottom surface. A side opening extends the axial length of the holder from the first opening to the second opening. Upon insertion of the holder into the panel through-slot, the holder is movable between an open position and a closed position. At the open position the holder side opening is aligned with a corresponding side opening of the panel. With the holder moved into the closed position, the holder side opening is blocked by inner walls of the panel through-slot. A probe cord slides through the side openings while the holder is in the open position. Once the holder is moved to the closed position, the probes cord is radially trapped within the holder.

Abstract: An ionization chamber for monitoring a radiation beam includes a housing having a primary beam passageway and a number of secondary beam cells that are adjacent to the primary beam passageway. The primary beam passageway passes entirely through the housing. In the preferred embodiment, a large-area beam measuring electrode and an array of small-area beam measuring electrodes are each coaxial with the primary beam passageway. Also, in the preferred embodiment, each secondary beam cell includes a beam measuring electrode. Because the portions of the radiation beam that enter the secondary beam cells do not pass through the ionization chamber, these portions do not contaminate the treatment beam, allowing the beam measuring electrodes within the cells to be dimensioned and configured so as to maximize signal strength.

Abstract: In a radiation emitting device, particularly in a radiation treatment device, the actual radiation delivered to an object via a radiation beam is adjusted dependent on the dimensions of an opening in a plate arrangement provided between a radiation source and an object so that the radiation output has a constant wedge factor over an irradiation field, regardless of the size of the opening. The wedge factor is defined as the ratio between a reference radiation output along a reference axis of the beam with a predetermined physical wedge in the beam path and an actual radiation output of the beam in a substantiallylossless beam path.

Abstract: An ultrasonic Doppler flow (i.e. blood) imaging and/or measuring system capable of adaptively suppressing stationary or slowly-moving non-flow (i.e. tissue) signals having variable spectra from recovered ultrasonic echoes. In accordance with the invention, the tissue signals are suppressed using a tissue rejection filter having an attenuation characteristic which is controllably shaped based upon measured estimates of at least one spectral characteristic of the tissue signals to be removed, thereby maximizing the rejection of tissue movement signals and minimizing undesired attenuation of the blood flow signals. In accordance with one embodiment of the invention, the tissue rejection filter is embodied as a complex notch filter for filtering the baseband components of the recovered ultrasonic echoes, which filter has a variable notch shape and position as adaptively determined in response to changes in estimates of the spectral components of the tissue signal portion of the recovered echoes.

Abstract: A method for enhancing an ultrasound image. The image is assumed to be in the form of an ordered array of pixels. Each pixel corresponding to the intensity of the echo generated by a corresponding voxel in an ultrasound energy field. Axial and lateral directions relative to the ultrasound beam used to generate the sound field are defined within the ordered array. The method of the present invention includes the steps of dividing the image into a plurality of processing blocks, picking blocks that satisfy certain statistical constraints for edge enhancement, enhancing the pixels in the selected blocks, and then displaying the pixels in each block, whether enhanced or not, that are above a display threshold for the block in question. The statistical constraints are determined by second order statistics with reference to the axial and later directions.

Abstract: A compounded field of view ultrasound image is derived from correlated frames of ultrasound image data. An operator manually translates an ultrasound probe across a patient target area. Frames of sensed echo signals are processed to detect probe motion without the use of a dedicated position sensor or motion sensor. Motion is detected by correlating the frames for probe translation among as many as 6 degrees of freedom. Image registration then is performed for correlated portions to compound a large ultrasound image. Such image encompasses an area larger than a single field of view image frame for the given manually-scanned transducer probe.

Abstract: An apparatus and method for removing noise from a signal S(x). The noise is removed by filtering S(x) through a low pass filter having an adjustable pass band. A control processor analyzes S(x) prior to S(x) being input to the low pass filter and adjusts the pass band in response to an estimate of the SNR or rate of change of S(x) such that the pass band is reduced when the estimated SNR decreases and the pass band is increased when the SNR increases. In embodiments in which the control processor utilizes the rate of change of S(x) to control the pass band, the pass band is reduced when the rate of change of S(x) increases and increased when the rate of change of S(x) decreases. In embodiments used in ultrasound applications, the estimate of the SNR can be obtained from x, the power in S(x), or the variance in the measured velocity. The estimate of the rate of change of S(x) may be computed from an estimate of the correlation distance in S(x).

Abstract: A system and a method for generating an ultrasound image of an interrogation region in an object with a transducer with a two-dimensional array of transducer elements, includes the steps of generating an ultrasound beam by activating many transducer elements of the two-dimensional array; electronically controlling the beam to illuminate substantially the same region from at least two orientations; capturing the echoes generated with the beam illuminating the object at different orientations; and analyzing the echoes from all directions to produce an image of the region of the object. The aperture of the transducer generating the beam is at least substantially equal to the aperture generated by a linear array of transducer elements extending across the substantially shortest distance between two opposite edges on the two-dimensional array. The ultrasound power emitted from the transducer elements is not spatially uniform, and the multiple echoes reduce speckle in the image.

Abstract: A method and an apparatus for positioning blocking elements (310, 320) in a collimator (4) is provided. The collimator (4) is located in a radiation emitting device (2) delivering a radiation beam (1) to an object (13). The collimator (4) includes a plurality of movable blocking elements (310, 320). The blocking elements (310, 320) are movable for defining an opening (330) for the radiation beam (1). After forming an opening (330) with the blocking elements (310, 320), a calibration tool (400) having a cross bar (410) is inserted in the opening (330) and the cross bar (410) is moved to a defined first position (500) in the opening (408) of the calibration tool. A group of blocking elements is then moved to the cross bar (410). The cross bar (410) is then moved to a defined second position (510) in the opening (408) and the a group of blocking elements is moved to the cross bar (410).

Abstract: A two-dimensional radiation emitter has a plurality of line sources, advantageously of Gd-153. The line sources are removeably retained in the emitter, and form an array. The most active line sources are located in the center region of the array, and the activity of the sources progressively diminishes from the center of the array to the ends of the array (where the least active line sources are located). As the line sources undergo radioactive decay, they are moved towards the ends.

Abstract: Apodization parameters for respective transducer elements are generated, for example, at a beam-former, by accessing a select look-up table. An apodization parameter generator circuit includes respective look-up tables for each of multiple window algorithms. The same look-up table is used for a given window algorithm regardless of (i) aperture size; (ii) whether performing transmit or receive beam-forming; and (iii) whether deriving elevation or azimuthal apodization parameters. Each of the multiple tables has a common, fixed number of entries. Such number is at least as big as the number of transducer elements along the longest axis of the host transducer array. For symmetrical tables, the number of entries is halved. A pointer into a look-up table is calculated from the elevational or azimuthal aperture size in elements ("N") and the location of the transducer element of interest ("n") along the aperture.