摘要:
The present invention provides a model and a method and apparatus for utilizing the model to simulate an imaging scenario. The model is mathematically defined by analytical basis objects and/or polygonal basis objects. Preferably, the model is a model of the human heart and thorax. Polygonal basis objects are only used to define structures in the model that experience torsion, such as certain structures in the heart that experience torsion during the cardiac cycle. The manner in which the basis objects comprising the model are transformed by scaling, translation and rotation is defined for each basis object. In the case where a basis object experiences torsion, the rotation of the basis object will change as a function of the length along the axis of the basis object about which rotation is occurring. During an imaging system simulation, the model is utilized by a forward projection routine, which integrates the linear attenuation coefficients associated with the rays emitted by a simulated x-ray source and collected by a simulated detector array to obtain line integrals corresponding to forward projection data. The forward projection data is then processed to take into account the physics of the imaging technology, the x-ray source and the detector array. The processed projection data is then processed and back-projected by a reconstruction modeling routine to produce a reconstructed representation of the model of the heart as a function of time.
摘要:
The invention provides tomographic image generation from four-dimensional projection data of an imaged object. The ability is provided to extract implicit information from time dependent aspects of volumetric projection data corresponding to multiple data acquisition cycles. The result is improved volumetric image quality from volumetric projection data previously used for slice by slice image reconstruction. The invention provides particular advantages for volumetric imaging of a patient's heart, or a portion thereof, at a selected phase of the cardiac cycle.
摘要:
A system for analyzing tissue samples, that generally comprises, a storage device for at least temporarily storing one or more images of one or more cells, wherein the images comprise a plurality of channels; and a processor that is adapted to determine the extent to which a biomarker may have translocated from at least one subcellular region to another subcellular region; and then to generate a score corresponding to the extent of translocation.
摘要:
An RF coil assembly for use in a multiple receive-channel MRI system is provided. The RF coil assembly is configured as a multi-turn-element RF coil assembly to operate as a surface-coil array in cooperation with the MRI system which is configured to operate in a multiple-channel receive mode.
摘要:
A magnet assembly system for use in an open Magnetic Resonance Imaging (MRI) system comprises a first assembly and a second assembly opposing each other in a longitudinally spaced apart relationship. The first and second assemblies generate a static magnetic field for use in imaging. Further provided is a plurality of support posts attached between the first and second assemblies for maintaining an open imaging volume between the first and second assemblies and for further providing structural support. Each of the support posts comprises a first support element and a second support element attached to first support element on the surface away from the imaging volume. A method for reducing vibration in an open MRI system comprises attaching a second support element to each of the support posts on a surface away from the imaging volume.
摘要:
An apparatus and method for Magnetic Resonance Imaging (MRI) by spiral trajectory scanning comprises an MR imaging device for acquiring and processing data samples of an object to be imaged, wherein the data samples are acquired by spiral trajectory scanning. An interface is coupled to the MR imaging device for receiving operator-defined spiral scanning parameters, and a computer is coupled to the interface and the MR imaging device. The computer is configured to generate an approximated spiral trajectory in k-space in accordance with operator-defined spiral scanning parameters. The approximated spiral trajectory is used by the MR imaging system to perform spiral trajectory scanning.
摘要:
The noise reduction system of the present invention takes into account that noise is random with little between images adjacent physically, and in sampling time. It also takes into account the fact that some sequences of images are cyclical and “wrap around” in time with the beginning closely resembling the end of the cycle. A filter was developed which would smooth noise in a direction along an edge, but will not blur across an edge. It operates by determining vectors tangential to a surface point p, at a current voxel, and projecting 4D data onto the tangential vectors. A curvature matrix B&agr;&bgr; is determined. The eigenvalues of curvature matrix B&agr;&bgr; are determined to result in three curvatures for 4 dimensions. If the sign of all of the eigenvalues is the same, the current voxel is filtered, else, it is unchanged. This filtering is repeated for a number of voxels as the current voxel within a desired region for a single iteration. Preferably, this is repeated for several iterations to result in filtered data with reduced noise and little change in detail. The filtered data may then be segmented to separate structures. The segmented structures may then be used in analysis, such as in medical diagnosis.
摘要:
A volumetric data set having a high intensity, dominant structure, near smaller, less intense structures is smoothed and segmented to separate the dominant structure. The dominant structure is masked out to result in the smaller, less intense structures which are displayed. For example, dominant structures such as the blood pool in atria, ventricles, and the aorta of a 3D angiography data set is segmented and removed from the data set using mathematical morphology operations to result in an enhanced data set. The enhanced data set is displayed by conventional means such as a maximum intensity projection (MIP) at different views to yield images of coronary arteries.
摘要:
A system for treating a prostate includes an acoustic carrier, a phase fresnel zone in a section of the acoustic carrier, and an acoustic transducer. The phase fresnel zone is formed in the acoustic carrier adjacent a first end of the acoustic carrier and extends at least partially around the outer surface of the acoustic carrier. An acoustic transducer is coupled to a second end of the acoustic carrier. In treating the prostate, which surrounds a urethra, the acoustic carrier is inserted into the urethra and positioned so that the phase fresnel zone is situated in a region of the urethra surrounded by the prostate. Acoustic waves are transmitted into the second end of the acoustic carrier and the phase fresnel zone focuses the acoustic waves to constructively interfere at the location in the prostate. By moving the acoustic carrier, the phase fresnel zone may be moved along at least a portion of the region of the urethra surrounded by the prostate while the acoustic waves are being transmitted.
摘要:
A system for analyzing tissue samples, that generally comprises, a storage device for at least temporarily storing one or more images of one or more cells, wherein the images comprise a plurality of channels; and a processor that is adapted to determine the extent to which a biomarker may have translocated from at least one subcellular region to another subcellular region; and then to generate a score corresponding to the extent of translocation.