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.

Abstract: A method and system of processing Doppler data includes determining a noise component independently of automatic signal analysis. A succession of frequency spectra is formed in response to receiving reflected energy from an object of interest. A Doppler waveform is then derived from the succession of frequency spectra. The execution of noise estimation is limited to time periods between peaks of the Doppler waveform, providing a first level of isolation from the true-signal processing. Implementation of the noise estimation is based upon portions of the frequency spectra that are independent of the portions from which the Doppler waveform is derived. This provides a second level of isolation. The determined noise component is used as a threshold level in subsequent derivation of the Doppler waveform. Preferably, there are multiple noise thresholds that are adaptively utilized to permit application of a short search block during Doppler frequency detection.

Abstract: A monitor system for acquiring medical data from a plurality of sensors adapted for attachment to a patient. The system is distributed over at least two geographically separate patient monitoring areas via a communication network and includes a portable monitor and at least two monitor docking stations. The portable monitor is adapted for coupling to the plurality of sensors, for receiving, processing and displaying patient data signals acquired from the plurality of sensors when said sensors are attached to the patient. At least one docking station is located in each of the two patient monitoring areas and are connected to one another for transmission of patient data therebetween via the communication network.

Abstract: An ultrasound system (50) estimates the speed of sound in the tissue (60) under examination. The ultrasound system obtains a series of test images (150) using different estimates of the speed of sound in the body tissue. For each image produced, the ultrasound system computes a function that is indicative of image quality for one or more regions of interest (152) in the test image. The image quality function exhibits a minimum or maximum when computed for a region of interest obtained at a speed of sound substantially equal to a true speed of sound in the tissue. The ultrasound system selects the test image having the minimum or maximum function value and obtains subsequent images of the tissue using the speed of sound used to obtain the test image selected.

Abstract: An MR pulse sequence for conducting fat- or water-suppressed multislice MR studies. Saturation prepulses are used less frequently than is conventional practice. Each time at least one saturation prepulse is used to saturate all slices in a group of slices, one line of MR data is acquired from each slice in the group without using any other saturation prepulse.

Abstract: A method for generating an ultrasound image that enhances regions occupied by non linear scattering media. The method utilizes first and second ultrasound pulses that are alternatively transmitted into the specimen being imaged. The first and second ultrasound pulses are amplitude modulated harmonic signals, the first ultrasound pulse differing from the second ultrasound pulse by the phase of the harmonic signal. The echo signals generated by these pulses are measured and combined. In one embodiment of the present invention, the first and second ultrasound signals differ by 180 degrees and the echo signals are combined by adding the echo signals generated by each of the ultrasound pulses.

Abstract: An image of an interrogation region of a patient's body is generated from the return signal from an ultrasound pulse, which is directed into the interrogation region by a transducer array, which may be linear (to create a planar image) or planar (to create a 3-D image). The time-domain signal back-scattered to the transducer is sensed at a reference plane (preferably, the transducer plane itself) and is transformed first by a temporal Fourier transform and then by a spatial Fourier transform, in order to generate an angular spectral decomposition of the back-scattered signal. This decomposed reference signal is then propagated to image planes (or lines) at depths other than at the reference plane, throughout the image volume. The resulting propagated signals are then inversely transformed twice, back into the time domain. An entire image is thus reconstructed from the back-propagated signal from a single input pulse.

Abstract: An ultrasonic diagnostic system is provided that removes the effects of image motion from the received Doppler information signals, allowing the display of a fluid flow image without image motion artifacts. The Doppler information signals received from an ultrasonic transducer include velocity components due to both the fluid flow through a subject as well as image motion. The Doppler information signals are demodulated to provide Doppler baseband signal samples containing a fluid motion component and an image motion component. An image motion vector is estimated from a comparison of consecutive image frames, and a relative Doppler frequency between the fluid motion component and the image motion component is derived utilizing the estimated image motion vector. A fluid motion vector can then be derived from the derived relative Doppler frequency.

Abstract: An apparatus for monitoring the expansion and contraction of the thoracic cavity of a patient caused by respirations comprises, generating means for generating an AC examination current signal, coupling means for applying the examination current signal to the patient so that the examination current passes through the thoracic cavity of the patient, but at least a portion of the current does not pass through the thoracic cavity of the patient, detecting means coupled to the coupling means for detecting an amplitude modulated voltage signal developed across the patient in response to the application of the examination current and variation of the transthoracic impedance of the patient due to respiration, and current modifying means coupled with the generating means for modifying the AC examination current during application to the patient so that the portion of the examination current which does not pass through the patient is at least partially compensated.

Abstract: An embodiment of the present invention is a disposable/reusable needle guide which can be: (a) utilized with many ultrasound probes; (b) attached and detached from such ultrasound probes easily and rapidly; and (c) utilized with biopsy needles. In particular, an embodiment of the present invention is a needle guide for use with an ultrasound probe which includes: (a) a clip for detachably affixing the needle guide to the ultrasound probe; (b) a clip lock for detachably locking the clip to securely affix the needle guide to the ultrasound probe; (c) a needle support, affixed to the clip, for supporting and positioning a needle; and (d) a needle cap, detachably affixed to the needle support, for supporting and positioning the needle; wherein the needle support and the needle cap include a snap locking for detachably affixing the needle support and the needle cap to each other.

Abstract: An ultrasonic imaging system has a three-dimensional acoustic display. Beam-formed ultrasound scan signals are separated into channel signals and are then filtered using head-related transfer function (HRTF) filters. An HRTF is associated with each of several points in an interrogation region. A filter coefficient processor selects, for each channel signal, a set of HRTF filter parameters according to which sample volume the channel signal comes from. Each HRTF parameter set defines left-ear and right-ear response functions to a calibration sound generated at a calibration point in a calibration space; the calibration point itself corresponds to a predetermined position in the interrogation region. The HRTF-filtered channel signals are then combined into left and right audio output signals which drive left and right speakers that the user listens to while performing the ultrasound scan.

Abstract: An ultrasound imaging system comprises a position location array adapted to be affixed to a surface layer of an imaging subject. The position location array comprises a plurality of electrodes disposed in a grid pattern within a flexible substrate. An imaging transducer having at least one element is operable to provide an acoustic pulse through the position location array and the surface layer in response to a driving signal and to provide a corresponding return signal in response thereto. A receiver is coupled to the imaging transducer to receive the return signal from the at least one element and provide a beamformed signal. A processor coupled to the receiver and the position location array forms an image from the beamformed signal that includes position coordinates that correspond to an intersection between the acoustic pulse and associated ones of the plurality of electrodes.

Abstract: A patient pallet has two sides, a proximal end and a distal end. The patient pallet is horizontally elongated and is positioned to support a human patient with the patient's body axis horizontal. The pallet is supported by a pedestal. The pedestal is vertically moveable so that the patient may be raised and lowered with respect to the floor. The pedestal receives the patient pallet so that the pallet can slide horizontally, parallel to the floor. A pallet support is horizontally spaced from the pedestal and is so located that the distal end of the patient pallet can be supported by the pallet support when the patient pallet is slid horizontally. In this way, the patient pallet is either supported by the pedestal alone or by the pedestal and the pallet support. In the latter instance, the patient pallet bridges between the pedestal and pallet support. Left and right horizontally elongated arm rests are provided.

Abstract: Radiation output directed toward at least one field of an object, such as a patient, is sensed, for example, during a session of radiation therapy. The accumulated dose delivered to the field is displayed and updated throughout the delivery of radiation. A prescribed dose profile may also be displayed simultaneously so the user can compare the accumulated dose with the prescribed dose profile over the irradiated field. Dose profiles--both prescribed and accumulated--are preferably stored in a memory unit. Profiles for several different fields at several different times may be stored and used to direct and monitor the course of radiation treatment.

Abstract: An ultrasonic transducer array has a piezoelectric ceramic layer that is separated in a longitudinal direction into n transducer groups. Each group is separated in a transverse direction into m elements. A double-sided flex circuit has a flexible, non-conductive base layer, through which conductive vias extend and are in electrical contact with a respective element. A conductive layer on a bottom side of the flex circuit is divided into a plurality of electrodes, each of which is in electrical contact with a respective one of the elements. For each group, electrically conductive traces connect predetermined ones of the flex circuit electrodes with external driving circuitry, and are located on a top side of the flex circuit. Transducer groups with different numbers of elements are provided, some with 1.5-D operation (with element pairs stimulated via a common trace) and some with 2-D operation (with separate traces for each element).

Abstract: A shielded electrical connector having an elongated annular housing composed of an electrically insulative material molded so as to form an elongated structure for the connector and at least a portion of a grasp for a user of said connector. The housing defines outside and inside surfaces and front and rear ends for said connector. A contact holding portion composed of an electrically insulative material is positioned inside said annular housing and includes a plurality of electrically conductive signal contacts positioned therein so as to be completely surrounded by, yet spaced a distance away from, the inside surface of the housing. An elongated annular electrically conductive shield having inner and outer sides is insert molded with the housing so as to be disposed between its outside and inside surfaces.

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 output factor over an irradiation field, regardless of the size of the opening. The output factor is defined as the ratio of the radiation output in air with a scatterer (such as shielding plates) in the beam path to the radiation output without the scatterer for a reference field.

Abstract: An interrogation region, such as a portion of a patient's body, is imaged as an unfiltered pattern of image elements, to each of which is assigned a numerical value such as brightness. One element is selected either automatically or manually as a reference element, which lies in a substantially homogeneous image portion. For ultrasonic imaging, the homogeneous portion preferably corresponds to a region of speckle noise. A reference histogram of the numerical values is then accumulated for all the elements in a region or window about the reference element. All of the remaining elements are sequentially designated as current elements, for each of which a current histogram is accumulated. Each current histogram is compared with the reference histogram using an error function for each corresponding pair of histogram bins. The error function values for all bins, which may be normalized and weighted, are used to generate a similarity value between the current and reference histograms.