Abstract: Systems, methods and apparatus are provided through which, in one embodiment, an X-ray source and collimator are positioned relative to an image receptor for imaging of a subject.

Abstract: The present invention includes a filtering apparatus for a CT imaging system or equivalently for an x-ray imaging system. The filtering apparatus may be translated along a first axis or a transverse axis to with respect to an attenuation pattern of a subject during an imaging session to reduce radiation exposure to anatomical regions of the subject sensitive to radiation exposure and/or regions from which data is not being acquired.

Abstract: A system and method of diagnostic imaging with reduced x-ray exposure to the scan subject during scanning includes acquiring a set of cardiac signals or other motion (cardiac mechanical motion or respiratory motion) related signals and determining and imaging profile therefrom. Pursuant to the imaging profile, voltage applied to an x-ray source is modulated to provide an energizing voltage during primary data acquisition stages and a reduced voltage during secondary or non-data acquisition stages. Voltage modulation repeats until sufficient data for image reconstruction has been acquired.

Abstract: A method and apparatus for smoothing speckle pattern and increasing contrast resolution in ultrasound images is provided. Compared to other frequency compounding techniques, wide-band harmonic frequency compounding reduces speckle noise without sacrificing the resolution. Compared to spatial compounding, wide-band harmonic frequency compounding is more robust against tissue motion because sequential vectors rather than frames are summed together for compounding. The method and apparatus is implemented by transmitting two or more firings, combining two or more of the firings coherently to extract the tissue-generated harmonic components, detecting the outputs of the coherent sums and detecting one or more firings before coherent sum, and finally combining all detected outputs to form the compounded image. The method and apparatus sums wide-band fundamental and wide-band harmonic images after detection to form a compounded image.

Abstract: A system and method are provided for activating inactive software options pre-installed on a device upon initialization of the device and thereby preventing installation during device operation. The invention includes receiving a request from a user at a centralized facility for access to an inactive option resident on the device. After validation of the request, an option-specific activation key or code is generated at the centralized facility using data from at least one of a user identifier, a system identifier, a host identifier, a use period identifier, and the selected option. The activation key is then transmitted from the centralized facility to the device whereupon only during initialization or reboot of the device is access to the inactive option automatically granted. The limiting of access to the inactive option until device initialization ensures that option enablement is prevented during device operation.

Abstract: A Magnetic Resonance Imaging (MRI) magnet field instability simulator (80) is provided. The simulator includes a rigid body motion generator (82) that simulates motion of one or more MRI system components. An eddy current analyzer (84) generates a magnetic stiffness and damping signal and an electromagnetic transfer function in response to the motions and a cryostat material properties signal. A mechanical model generator (86) generates a mechanical disturbance signal and a mechanical model of one or more MRI system components in response to the motions and the magnetic stiffness and damping signal. A structural analyzer (88) generates a motion signal in response to the mechanical model. A field instability calculator (90) generates a field instability signal in response to the electromagnetic transfer function and the motion signal. A method of performing the same is also provided.

Abstract: The present invention is directed to a method of shimming a magnet assembly of an MR imaging system such that a desired B0 field strength may be created with minimal inhomogeneities therethrough. With this method, sufficient shimming of the magnet assembly may be achieved without requiring mechanical variations to the magnet assembly after the magnet assembly has been assembled. The invention analyzes variations from the desired B0 field and inhomogeneities at a number of target points along the magnet assembly or B0 field. A comparison is then made at each point to determine a shimming or weighting factor such that the desired overall B0 field strength and targeted field homogeneity is achieved. Active and/or passive shim elements may then be incorporated into the magnet assembly at each target point to achieve the desired overall field strength and minimum overall field homogeneity.

Abstract: A method and apparatus for eliminating the picket fence effect in PET scanners where the scanner includes a master clock and an event processing circuit that generates time stamps during each clock cycle, the scanner also including a coincidence detector that compares the time stamps during each clock cycle to identify coincidence events, the method including the steps of, for consecutive master clock cycles, identifying an overlap period that includes a portion of a first of the master cycles adjacent a second of the master cycles, adding an overlap period that occurs during the overlap period to the second of the master cycles to generate an extended cycle, identifying overlap events that occur during the overlap period in the first of the master cycles, copying the overlap events to the overlap period in the extended second cycle and performing a comparison of the events in the extended cycle to identify coincidence event pairs

Abstract: A system and method are disclosed using incremental table motion and partial data acquisition for increased volume coverage to reconstruct MR images across a large FOV without significant slab-boundary artifacts. At each table position, full z-encoding data are acquired for a subset of the kx-ky data. The table is stepped through a number of positions over the desired FOV and MR data are acquired over the plurality of table increments. Since full z-data are acquired for each slab, the data can be Fourier transformed in z, sorted, and then aligned to match anatomic z locations. The fully sampled and aligned data is then Fourier transformed in x and y to reconstruct the final image that is free of slab-boundary artifacts.

Abstract: A system and method are disclosed using continuous table motion while acquiring data to reconstruct MR images across a large FOV without significant slab-boundary artifacts that reduces acquisition time. At each table position, full z-encoding data are acquired for a subset of the transverse k-space data. The table is moved through a number of positions over the desired FOV and MR data are acquired over the plurality of table positions. Since full z-data are acquired for each slab, the data can be Fourier transformed in z, interpolated, sorted, and aligned to match anatomic z locations. The fully sampled and aligned data is then Fourier transformed in remaining dimension(s) to reconstruct the final image that is free of slab-boundary artifacts.

Abstract: A mechanically adjustable brake for use with a C-arm x-ray apparatus is generally comprised of a brake handle and an eccentric shaft support which, when rotated using the handle, actuates a cam and presses a brake pad into the C-arm. Movement of the C-arm is thus restricted when the brake is applied. The brake mechanism specifically includes a brake handle, a brake shaft, a cam mounted on the brake shaft, a plunger having a first end engaged with the cam and a second end having a brake. The brake handle is used to rotate the brake shaft and the cam, the cam pushes down on the plunger and the brake engages the C-arm. The brake mechanism further comprises a plunger support, a spring that is compressed when the brake is actuated and is decompressed when the brake is released thus permitting movement of the C-arm. The brake shaft is connected to the brake handle using an eccentric shaft support.

Abstract: A real-time imaging and visualization method and system that allows multiple field-of-view imaging on multiple receiver channels is disclosed. The method and system implement a semi-bit reversed modified phase-encoding scheme to acquire identical data over all receiver channels, and to reconstruct independently on each channel an image thereby providing multiple FOV images. The method and system provide for real-time catheter tracking where separate receiver channels collect anatomical roadmap data, guidewire data, and catheter data. The present invention uses a loopless antenna to acquire projection images thereby allowing the entire antenna and structures within its diameter of sensitivity to appear as a bright signal and a long narrow connected region. The present invention allows for very narrow FOV imaging for guidewire and catheter channels as well as full FOV imaging for roadmap image reconstruction.

Abstract: The present invention provides a detector for a CT system. The detector includes a scintillator with built-in gain for receiving and converting high frequency electromagnetic energy to light. Each scintillator is formed of a scintillating material and an optically stimulated material. The components may be intermixed with one another to form a single composite structure or formed into layers to form a single layered structure. The scintillator may be incorporated into the detector array of any CT system including medical diagnostic systems and package/baggage inspection systems.

Abstract: A system and method is disclosed for in-field communication connectivity verification reporting between centralized on-line centers, and a number of in-field subscribing stations. The substations each have associated therewith an in-field product controlled by software which requires periodic upgrading, maintenance, service, and general monitoring. The system and method includes a computer program and a computer data signal embodied in a carrier wave for carrying out the process, which includes submitting customer and product data, and a user selected mode of notification of completion electronically to a centralized on-line center, which in turn creates a configuration module based on the submitted customer and product data. The configuration module is then transmitted to the subscribing station by the on-line center. The configuration module is loaded into the subscribing station to allow future communications between the on-line center and the subscribing station.

Abstract: A method of resampling medical imaging data from a first spatial distribution of data points onto a second spatial distribution of data points. The method includes determining a matrix of coefficients for resampling data from the second spatial distribution onto the first spatial distribution and inverting a matrix based on the matrix of coefficients to determine forward resampling coefficients for resampling data from the first spatial distribution to the second spatial distribution. Then, resampling data from the first spatial distribution onto the second spatial distribution using the forward resampling coefficients.

Abstract: A method and apparatus is disclosed in which a two-tiered approach is taken to first grade a patient to identify the presence of any suspected stenosis, and then a second step is used to acquire more detailed information to grade the stenosis. The invention includes performing a screening study by acquiring a first MR image having a low resolution to scan a suspected stenosis region. After analyzing the first MR image to identify a suspected stenosis within the suspected stenosis region, a more detailed study is performed by acquiring a second MR image having a higher resolution than the first MR image to scan the identified suspected stenosis. If no lesions, or stenotic vessels, are identified after the first MR image, the second MR image need not be obtained.

Abstract: An automatic and adaptive MR data selection technique for use with a multi-receiver coil assembly in an MR imaging device is disclosed. The invention includes acquiring image data from a plurality of receiver coils and determining an index gauge for each of the images. The index gauge is a representation of the position of a given receiver coil within a desired field-of-view (FOV). The index gauges are compared and any image data set having an index gauge demonstrating a less than optimal position of the given receiver coil with respect to the desired FOV is removed based on the index gauges and the comparison. A final image can be reconstructed using the remaining image data sets. The final image is reconstructed from data having overall reduced noise, and therefore reduced artifacts.

Abstract: A variable friction disc brake for use with a C-arm x-ray imaging apparatus interposed between the support arm and yoke of the imaging apparatus. The variable friction disc is generally comprised of ring having a gap, width both sides of said gap having apertures therethrough such that a bolt may be inserted into said apertures and used to adjust the width of the gap, and the tension on the ring.

Abstract: Automatic coil selection is based on determining an index gauge for a corresponding k-space data line acquired for each preselected coil during a prescan. Reliance on manual coil selection and markers is eliminated by adaptively determining the coils of an MR system that produce a preferred sensitivity to a desired field-of-view (FOV). The fast scan data is used to determine those coils most sensitive to the FOV and reject coil(s) least sensitive. Using only data acquired with the most sensitive coils, SNR is increased and unwanted artifacts are reduced in the final data acquisition and image reconstruction. Through automatic and adaptive selection/deselection, the invention reduces the susceptibility to human error, and therefore results in higher quality images.

Abstract: The present invention is directed to a method and apparatus of cardiac CT imaging. The present invention utilizes ECG signals as well as mechanical motion signals of a cardiac region of a subject to correlate CT data acquired of the subject with the phases of the subject's cardiac region. The present invention contemplates measuring mechanical gatings of the heart by measuring changes in pressure, sound, or blood flow acceleration within the cardiac region. The mechanical gatings are then used with ECG data to correlate acquired imaging data with phases of the cardiac region for subsequent image reconstruction.