Abstract: A method and apparatus for correcting ghosting artifacts that are related to Maxwell fields and/or other perturbation magnetic fields is disclosed. The method and apparatus includes acquiring MR image n-space data and an MR reference scan, each having perturbation field effects therein. After determining phase correction values from the MR reference scan and reconstructing an MR image using the phase correction values, a projection phase error is calculated from the reconstructed MR image and then subtracted from the reference scan, the result of which is used to determine a new set of phase correction values. The new set of phase correction values is applied to the acquired MR image data to reconstruct a new image. The reconstructed new image can then be reused to calculate a new projection phase error, which again is subtracted from the reference scan data and the process is repeated until an image of desired ghost artifact reduction is achieved.

Abstract: An x-ray imaging apparatus having an anode stem assembly with explosion-bonded joints is provided. Explosion-bonding the components of an anode stem assembly to one another provides a hermetic seal with increased reliability as well as reducing the anode stem's susceptibility to thermal and/or mechanical induced fracture. By eliminating the need for brazing and/or welding material within the anode stem, the present invention also provides an anode stem with increased heat transfer capabilities. Further, providing explosion-bonded joints creates a simple joint microstructure absent any voids and temperature-induced phases not previously present in the anode stem materials.

Abstract: A method and apparatus are disclosed for achieving suppression of blood pool signal to detect myocardial infarction using MR technology. After administering a contrast agent into the blood stream of a patient, an RF pulse sequence is applied that includes a slice-selective inversion pulse to suppress normal myocardial tissue followed by a notched inversion RF pulse designed to suppress blood pool in and around the region-of-interest. MR data is then acquired within the region-of-interest that not only has signals from normal myocardial tissue suppressed, but also has blood pool signal suppression to improve delineation of infarcted myocardium from the ventricular blood pool and normal myocardium.

Abstract: A system for and method of configuring capital equipment in an on-line marketplace environment provides for the generation and acceptance of purchase orders in an automated and distributed environment. Using this system or method, a purchaser may view basic product information at a business-to-business exchange web page and select a link to display a product provider web page. After the purchaser contacts the product provider to configure a particular capital equipment product, the product provider posts a complete product specification and price quotation on-line at the product provider web page. A reference to the quote is displayed at the exchange web page, and the purchaser may view the quotation on-line and accept the quotation at the exchange web page.

Abstract: An improved scintillator detector cell geometry for converting radiation to light with improved light collection is provided. Shaping the exit face of a scintillator to increase the surface area of the exit face results in a decrease in a fraction of angles that undergo total internal reflection within the scintillator. The scintillator has the advantage of preventing total internal reflection parallel, as well as perpendicular, to the detecting surface of a light collection device. Further, providing a specular reflector on a hemispherical dome portion of the radiation detecting surface of the scintillator results in reduced bounce-off the specular reflector before light contacts the scintillator-photodiode interface. Furthermore, implementing a convex shape when coated with the specular reflector increases the fraction of light directed toward the photodiode compared to a plane surface parallel to the photodiode.

Abstract: The invention includes a technique for efficient multi-slice fast spin echo image acquisition with black blood contrast in cardiac imaging. The technique includes applying a non-selective inversion pulse, followed by a re-inversion pulse that is slice-selective over a region encompassing a plurality of slice selections. Execution of a series of RF excitation pulses with fast spin echo readout is timed such that signal from blood is near a null point before acquiring data for each spatial slice. For greater contrast consistency, the flip angles for the excitation pulses occurring before the null point can be reduced, and those occurring after the null point can be increased.

Abstract: The present invention discloses a method of aligning scintillator crystalline structures for computed tomography imaging and a system of use. Crystal seeds are deposited inside a glass melt and are then grown to form a plurality of layer crystallites. While growing the crystallites, a field is applied to align each crystallite structure in a uniform orientation. As a result, the crystallites are configured to reduce light scattering and improve the overall efficiency of the CT system. A CT system is disclosed implementing a scintillator array having a plurality of scintillators, each scintillator being formed of a plurality of uniformly aligned crystallites. Each crystallite includes a receiving surface and an exiting surface configured perpendicular to an x-ray beam. Further, the receiving surface and the exiting surface are connected by a plurality of surface walls arranged parallel to the x-ray beam.

Abstract: The present invention provides a detector for a CT imaging system. The detector includes a focused scintillator for receiving and converting high frequency electromagnetic energy to light energy. The detector further includes a photodiode positioned adjacent to the scintillator and configured to receive light energy discharged through a light exiting surface of the scintillator. The detector also includes electrical leads to transmit signals from the photodiode to a data processing unit for image construction. The CT system also provides for a gantry having an output for projecting high frequency electromagnetic energy toward the scintillator. A method of use and method of fabricating the tapered scintillators of the tapered scintillator array are also disclosed.

Abstract: A method and apparatus for correcting ghost artifacts that are related to orthogonal perturbation magnetic fields is disclosed. The technique includes acquiring MR data and an MR reference scan, each in the presence of orthogonal perturbation magnetic fields. However, the region of interest for the MR reference scan is limited to a relatively narrow band within the imaging subject. Preferably, the narrow band is selected in the vicinity of the magnet iso-center and parallel to the readout direction. Alternatively, the narrow band can also be selected in the limited region where the orthogonal perturbation fields are either minimal or constant along the phase encoding direction, and parallel to the readout direction. The selection of the relatively narrow band is accomplished by either spatially saturating surrounding regions, or using a two-dimensional spatially selective RF pulse.

Abstract: A method and system for processing data in a PET scanner is provided, in which a projection plane data set is converted into a two-dimensional sinogram data set. The method includes (1) selecting a subset of projection plane data from the projection plane data set, (2) performing a set of Fourier transforms, respectively, on a plurality of data rows within the subset of projection plane data to obtain a transformed data set, and (3) performing an additional set of Fourier transforms on the transformed data set to obtain intermediate results. The additional set of Fourier transforms includes a plurality of individual Fourier transforms respectively corresponding to a plurality of combinations of at least two indices.

Abstract: The present invention is directed to a method and apparatus for administering computed tomography (CT) imaging scans with reduced radiation dosage. The present invention includes an algorithm that allows for reduction of the sampling rate and tube current to acquire a first set of angular views. A second set of angular views is then created using interpolation from the first set of angular views. The sets of angular views are then combined to form a final set of angular views that are used to create an aliasing-free image of the scan subject. The present invention is particularly applicable for scanning centralized small objects such as the heart or the head and also is particularly useful in acquiring imaging data of pediatric patients.

Abstract: A method for producing a base tomographic image and a subsequent tomographic image of an object using projection data acquired in a scan with a system which includes an x-ray source and a detector array which includes a plurality of detectors. The method includes applying a segmentation algorithm to the projection data to generate base image data comprising a plurality of segments; generating image data for each segment; generate subsequent image data based on image data of each segment; and communicating image data, segments, subsequent image data, or base image data to a remote facility via a network. The remote facility provides remote services.