Abstract: A method of generating an adiabatic FM pulse, comprising: selecting a starting trajectory for the pulse; and determining a velocity profile along the trajectory by constraining at least a portion of the velocity profile to fulfill an adiabatic condition other than a frequency frame adiabatic condition. Preferably, the other adiabatic condition is one defined in a double-rotating reference frame.

Abstract: A method of generating an adiabatic FM pulse, comprising: selecting a starting trajectory for the pulse; and determining a velocity profile along the trajectory by constraining at least a portion of the velocity profile only to fulfill an adiabatic condition other than a frequency frame adiabatic condition. Preferably, the other adiabatic condition is one defined in a double-rotating reference frame.

Abstract: A short radio frequency coil for magnetic resonance imaging of the head to provide a homogeneous magnetic field including parallel conductors forming a first cylindrical portion with end rings supporting the conductors which then continue at an angle to form the frustum of a cone and further continuing to form a reduced diameter second cylindrical portion. A third conductive end ring of reduced diameter positioned at the open end of the second cylindrical portion supports the end of the conductors and provides a reduced diameter opening. An asymmetrical coil surrounds portions of the radio frequency coil including the first cylindrical and frustum of a cone portions.

Abstract: A patient alignment device is disclosed for use in open magnet MRI having a movable patient table to move a patient within the open magnet MRI in order to position a desired patient scan area accurately within the field-of-view (FOV) of the open magnet MRI. A first alignment light is placed on the outer periphery of the upper magnetic structure of the open MRI to emit a light beam in longitudinal alignment with a center point of the FOV. A second alignment light is positioned to emit a second light beam downwardly from the upper magnetic structure to indicate an interior reference point of the FOV. The second alignment light is then used to reposition a patient within the open magnet MRI without having to withdraw the patient from the open magnet MRI.

Abstract: A retainer includes a base portion, a plurality of prongs, and a retention clip. The base portion has an inner bore engageable with a threaded stud extending from the mounting surface. The prongs extend outwardly from the base portion and are slidable into a bore of a device to be mounted to the mounting surface. The retention clip is formed by an outer distal end portion of the prongs and is configured to retain the device on the mounting surface by snap-locking onto the device when the device is slid onto the retainer. The prongs outer distal ends that are compressibly spaced apart from one another. In order to facilitate release of the device from the mounting surface, a pair of finger pads may be located at the outer distal ends of the prongs. The retainer is well-suited for mounting a telemetry antenna on a surface such as a ceiling and, in fact, can reduce antenna installation time by 75% when compare to prior known systems.

Abstract: The present invention relates to magnetic resonance imaging (MRI) and includes a method and apparatus to track motion of anatomy or medical instruments, for example, between MR images. The invention includes acquiring a time series of MR images of a region of interest, where the region of interest contains the anatomy or structure that is prone to movement, and the MR images contain signal intensity variations. The invention includes identifying a local reference region in the region of interest of a reference image and acquired from the time series. The local reference region of the reference image is compared to that of the other MR images and a translational displacement is determined between the local reference region of the reference image and of another MR image. The translational displacement has signal intensity invariance and can accurately track anatomy motion or the movement of a medical instrument during an invasive procedure.

Abstract: A multi purpose interconnect assembly between upper and lower helium vessels in a recondensing superconducting magnet to provide isothermal connections to extend the ride-through period, and to provide for helium liquid and gas passage, electrical interconnections, and to accommodate differential thermal contraction and expansion.

Abstract: A method and an apparatus for wall filtering the receive signal in each receive channel of an ultrasound imaging system prior to analog-to-digital conversion. Large-amplitude echoes corresponding to stationary or very slow-moving tissue are removed before they saturate the inputs to the analog-to-digital converters (ADCs) in the receive channels. By first removing the wall signal, the gain of the TIC amplifier in the receive channel can be increased without saturating the (ADC). This additional amplification will increase the small flow signals, mapping them into higher bits of the ADC, thereby allowing more sensitive detection of weak blood flow in the human body.

Abstract: The present invention relates generally to magnetic resonance imaging (MRI), and more particularly to a method and apparatus for efficient MRI tissue differentiation using an RF pulse designed to provide a frequency response combining a magnetization transfer contrast and fat saturation simultaneously. The invention includes creating a spectrally selective suppression pulse having an RF pulse profile designed to produce a frequency response with adequate fat suppression and selecting a spectrally selective suppression amplitude to produce a magnetization transfer contrast between two different tissue types, such as between proteinated tissue and water-based tissue. The invention also includes applying the spectrally selective suppression pulse with a flip angle selected to optimize fat suppression and magnetization transfer contrast saturation simultaneously.

Abstract: An x-ray tube casing coating prevents lead contamination of oil. The aluminum casing housing an x-ray tube has a lead lining with a top surface and a bottom surface, and is exposed to a dielectric cooling oil. An electroplating material is applied to both the top and bottom surfaces of the lead lining, forming an electroplated layer between the lead lining and the casing to prevent lead contamination of the dielectric cooling oil.

Abstract: A rotating x-ray tube comprises an anode assembly having an anode target for distributing heat generated at a focal spot. The x-ray tube further comprises a cathode assembly for producing X-rays upon impact with the anode. A target angle matching cathode cup structure is associated with the cathode assembly. The angled cathode cup structure creates a parallel surface between the cathode and the target to provide a focused electron beam.

Abstract: A method and an apparatus for suppressing background noise in spectral Doppler imaging using adaptive noise-reduction low-pass filters. A pair of adaptive low-pass filters are arranged in the two audio Doppler channels for suppressing background noise in the audio Doppler data. The low-pass filtering can be implemented in the frequency domain, i.e., before the IFFT operation, or in the time domain, i.e., after the IFFT operation. Maximum frequency traces are fed into a filter selection block which prescribes the filter cutoffs of the low-pass filters.

Abstract: A method of peripheral MR angiography is provided for imaging an artery or other vessel, wherein the vessel is of such length that MR data must be acquired at each of a plurality of scan stations spaced along the vessel. In accordance with the method, a contrast agent is intravenously injected, in order to provide a bolus which successively flows to each of the scan stations. After acquiring an initial subset of the MR data associated with a given scan station, the bolus is tracked to determine whether it has arrived at the next-following scan station. If so, at least some of the MR data associated with the next scan station are then acquired. However, if it is found that the bolus has not yet arrived at the next scan station, acquisition of further data at the given scan station is continued.

Abstract: Functional filter elements are linked in a multi-pass filter framework that forms part of an MRI system. The filter framework is configured by a set of parameters selected by the operator to perform smoothing and edge sharpening functions on acquired MR images. The functional filter elements used during each pass through the filter framework and the number of passes through it are configurable to obtain a wide variety of visual effects on medical images.

Abstract: A system and method for the acquisition of preferential arterial and venous images is disclosed. The invention includes setting a noise level in the phase image, that is proportional to the velocity encoding value, at a threshold level above the venous signal but below the arterial signal during a systolic portion of the cardiac cycle and acquiring a phase contrast MR image during the systolic portion that effectively acquires the arterial signal and suppresses the venous signal. During the diastolic portion of the same R—R interval, the velocity encoding value is then set to establish a noise threshold level in the phase image lower to a value below the venous signal but above the arterial signal to acquire the venous signal and suppress the arterial signal. In this manner, either an arterial only image or a venous only image can be displayed. Alternatively, the images can be combined to create a higher SNR arterial and venous image.

Abstract: A method and apparatus for configuring an ultrasound imaging system at a remote location by obtaining an encrypted feature key from a central location (e.g., via telephone) and then inputting that feature key into the ultrasound imaging system using an operator interface (e.g., a keyboard). To validate the feature key, the ultrasound imaging system decrypts the encrypted data and then compares the decrypted data to validation data pre-stored in the system. If the decrypted data matches the validation data, then the optional feature identified by the feature key will be enabled each time the system is booted or initialized. Optionally, an expiration date can be associated with the activated option, after which date the feature will be disabled when the system is initialized. Similarly, an activated optional feature can be disabled at a remote location by the input of an encrypted key obtained from a central location.

Abstract: An ultrasound probe having an integrated user-operable switch mechanism with two or more positions for respectively requesting activation of a single function or multiple functions. For example, the user-operable switch mechanism may be of the type having only “on” and “off” positions. In response to movement (e.g., by depression, rotation or sliding) of the switch to the “on.” position, the system host computer will activate the associated system function in accordance with the current order of prioritized tasks to be performed. For example, the switch could be mapped to a freeze or print function. Alternatively, the user-operable switch may be of the type having multiple positions (e.g., a sliding switch or a rotary switch) corresponding to multiple functions.

Abstract: The present invention relates to magnetic resonance imaging (MRI) and includes a method and apparatus to rapidly acquire T2 weighted MR images in a repetition time comparable to times usually associated with T1 weighted imaging. The invention also includes a pulse sequence for use with MR image acquisition to accomplish the foregoing. Two embodiments are disclosed, both of which have in common the use of a pulse sequence that has a first and second RF pulse, each RF pulse separated by an interval &tgr; and wherein the phase of the second and subsequent RF pulses is incremented linearly so as to spoil undesirable RF signal coherences so that the system can operate in steady state and acquire pure T2 weighted image in a time (TR) usually associated with T1 date acquisition.

Abstract: An apparatus for determining the quality of X-ray tubes by analyzing filmed images of the focal spots produced by the tubes. In an exemplary embodiment of the apparatus, a slide scanner receives a filmed focal spot from an X-ray tube and scans it to produce a digital version of the focal spot. The digital focal spot is then analyzed by a personal computer to determine parameters relating to the focal spot such as its background and peak optical density, line spread function, modulation transfer function, skew, and loading. These parameters are then compared to parameter standards to determine whether the X-ray tube should be accepted or rejected under current quality standards.

Abstract: An exposure management and control system and method for x-ray technique selection is provided. Optimal x-ray technique, which affects image quality, can be accurately predetermined to use for any application. A patient model is combined with a closed loop brightness control, using a parameter that does not affect image quality. This is used to create a control system that operates as a knowledge based control system. The x-ray system brightness control system comprises a first and second regulator. The first regulator is an image quality, or brightness, regulator. The brightness regulator can have multiple functions, such as peak mA control, power limiter, skin dose limiter, and an override function. The second regulator is a dose error regulator. The second regulator is independent of the first regulator, and cooperates with the first regulator to provide x-ray technique optimization independent of brightness control.