摘要:
One aspect of the present invention is a method for reconstructing computed tomographic (CT) images. The method includes generating a plurality of projection data, calculating a plurality of base weights using the projection data for each series of images to be reconstructed, storing the base weights in an external memory, and applying a z-smoothing module to the base weights to determine a plurality of final weights. The view weighting process then includes applying the final weights to the projection data for each image.
摘要:
One aspect of the present invention is a method for reconstructing an image of an object utilizing a computed tomographic (CT) imaging system. The method includes steps of: helically scanning an object; interpolating an axial fan beam set of projection data as a vector function {right arrow over (R)}a from a fan beam set of projection data from the helical scan {right arrow over (R)}hi, where i=1, . . . , n is a row index and n represents a of number of rows of the detector array, using a relationship written as: R → a ( β , γ ) = ∑ i = 1 n w i ( β ) R → h i ( β , γ ) , where wi(&bgr;) is a weighting function written as: w i = ∑ j = 1 m f ( β - β j ) , where m is a number of images used for z smoothing, &bgr;j is a gantry rotation angle for a plane of reconstrution of a jth image, and f ( x ) = { g ( x ) , &LeftBracketingBar; x &RightBracketingBar; ≤ β b 0 , &LeftBracketingBar; x &RightBracketingBar; > β b where constants β b = 2 π p , and g(x) is either a linear or non-linear function.
摘要:
A stable aqueous pharmaceutical formulation comprising a therapeutically effective amount of antibody not subjected to prior lyophilization, a buffer maintaining the pH in the range from about 4.5 to about 6.0, a surfactant and a polyol is described, along with uses for such a formulation.
摘要:
A nuclear imaging system (10) includes a crystal identification system (40) which receives a flood image (30) which includes a plurality of peaks, each peak responsive to radiation detected by a corresponding scintillator crystal. A crystal identification processor (42) partitions the flood image (30) into a plurality of regions (56), each region being masked to correspond to one of an array of nuclear detectors. A model image (62) is generated in which the at least one Gaussian models represents the identified peaks. Misidentified peaks in the model image (62) in which locations of the peaks in the flood image (30) differ from the corresponding scintillator crystal are determined and the locations of the misidentified peaks in the flood image (30) are corrected. A calibration processor (43) corrects geometric distortions in acquired projection data according to the corrected peaks.
摘要:
A method and apparatus for quickly rendering thick CT slice images wherein the data corresponding to an optimal number of slice images to be combined to generate a thick image and the data set required to generate the thick image are determined as a function of an optimal Z-smoothing factor and wherein Z-smoothing is implemented in software that performs quickly and is useable with any helical weighting algorithm and Z-smoothing function.
摘要:
There is therefore provided, in one embodiment of the present invention, a method for reconstructing a volume image of an object. The method includes steps of scanning an object with a multislice computed tomographic (CT) imaging system having a multislice detector array to acquire projection data of a volume of the object; filtering the acquired projection data; and backprojecting the filtered projection data to reconstruct voxels of the volume image. The multislice detector array has a plurality of rows and columns of detector elements and the backprojecting includes interpolating the filtered projection data across both rows and columns of the multislice detector array.
摘要:
A method for reconstructing an image of an object utilizing a computed tomographic (CT) imaging system having a radiation source configured to project a beam of radiation through an object and towards a multislice detector array configured to sense attenuation of the radiation passing through the object; the method includes helically scanning an object to acquire a plurality of slices of projection data, generating a separate projection dataset for each of N separate detector rows wherein the separate projection datasets include detector row projection data and detector row conjugate projection data, combining the detector row projection data and the detector row conjugate projection data, and helically weighting the combined projection data using a combined helical weighting and conjugate data weighting algorithm such that a greater weight is applied to combined center row projection data than to at least one outermost detector row projection data.
摘要:
A method for computing a natural logarithm function includes partitioning a mantissa region between 1 and 2 into N equally spaced sub-regions; precomputing a reference point ai of each of the N equally spaced sub-regions, where i=0, . . . ,N−1; selecting N sufficiently large so that, within each sub-region, a first degree polynomial in m computes log(m) to within a preselected degree of accuracy for any m within the sub-region, where m is a mantissa of a binary floating point representation of a variable x; and computing a value of log(x) for a binary floating point representation of x stored in a memory of a computing device utilizing the first degree polynomial in m.
摘要:
There is therefore provided, in one aspect, a method for imaging an object utilizing a computed tomographic (CT) imaging system having a rotating gantry, a multislice detector array on the rotating gantry and using at least n>1 rows of detector channels, and a radiation source on the rotating gantry configured to project a beam of radiation towards the multislice detector array through an object to be imaged. The method includes helically scanning the object with the CT imaging system at a pitch p>n to acquire projection data from the n rows of detector channels; applying a combined helical weight and conjugate weight to at least a portion of the acquired projection data to produce virtual projection data compensating for incomplete helical row data of the acquired projection data; and reconstructing an image of the object utilizing the acquired projection data and the virtual projection data.
摘要:
A stable aqueous pharmaceutical formulation comprising a therapeutically effective amount of an antibody not subjected to prior lyophilization, a buffer maintaining the pH in the range from about 4.5 to about 6.0, a surfactant and a polyol is described, along with uses for such a formulation.