摘要:
A method for generating an image of an object using a computed tomography (CT) imaging system, which includes at least one x-ray detector array and at least one rotating x-ray source projecting an x-ray beam, includes the steps of identifying a physiological cycle of the object (the cycle comprising a plurality of phases); selecting at least one phase of the object; collecting at least one segment of projection data for each selected phase of the object during each rotation of each x-ray source; generating a projection data set by combining the projection data segments; generating a cross-sectional image of the entire object from the projection data set; and communicating the image or data associated with the image to a remote facility. The remote facility provides remote services over a network.
摘要:
The present invention, in one form is an imaging system for generating images of an entire object. In one embodiment, a physiological cycle unit is used to determine the cycle of the moving object. By altering the rotational speed of an x-ray source as a function of the object cycle, segments of projection data are collected for each selected phase of the object during each rotation. After completing a plurality of rotations, the segments of projection data are combined and a cross-sectional image of the selected phase of the object is generated. As a result, minimizing motion artifacts.
摘要:
A method and apparatus for imaging a heart with a scanning computed tomography (CT) imaging system. A cardiac cycle of a patient is measured. The patient's heart is then scanned with the scanning CT imaging system at an angular rate asynchronous to the measured cardiac cycle to obtain image data. An image of the patient's heart is then assembled from chronologically discontinuous segments of the image data. The image is representative of a selected portion of the cardiac cycle.
摘要:
Methods and corresponding apparatus for imaging a portion of a patient's body with a computed tomographic imaging system configured to scan the patient's body at a cyclically varying view angle, in which the imaging system includes a radiation source and detector array providing a fan angle width of image data. In one embodiment, the method includes axially scanning the portion of the patient's body, gating the radiation source on over less than a 360 °view angle cycle of the axial scan, acquiring image data of the portion of the patient's body during at least a portion of the time the radiation source is gated on, and assembling the acquired image data into an image of the portion of the patient's body.
摘要:
One aspect of the present invention is a method that includes helically scanning an object at a selected helical pitch to acquire projection data of the object. The acquired projection data includes conjugate samples from single rows of the detector array of the CT imaging system and interrow samples. Projections in a plane of reconstruction (POR) are estimated based upon a selection of the projection data from the group consisting of the conjugate samples from at least one of the single rows, the interrow samples, and combinations thereof, the selection dependent upon the selected helical pitch. The estimated projections are filtered and backprojected to reconstruct at least one image of the object.
摘要:
A method is described for evaluating substance scoring, the scoring based on imaging system-generated images of an object having regions of interest due to possible presence of the substance, the method including the steps of simulating the regions of interest using a phantom having a plurality of volumes, each volume having dimensions simulating dimensions of a region of interest, each volume having a density representative of a substance density; generating images of the phantom; scoring the substance based on the phantom images; and comparing results of the substance scoring to expected phantom-image results. The above-described phantom and method allow a scoring system user to verify substance scoring accuracy and to compare scores resulting from different imaging systems, scanning methods and reconstruction algorithms.
摘要:
A method of evaluating a substance scoring system comprises acquiring data from a phantom using an imaging system, moving at least a portion of the phantom during the acquiring step, and generating an actual substance score for the phantom based on the data acquired using the imaging system. The phantom simulates a human organ such as a human heart. The phantom is provided with a motion profile that simulates a motion profile of the human organ.
摘要:
Image reconstruction time in a CT scanner is enhanced by using a pipeline structure and interpolation techniques to identify each detector for use in back projection of radiation aborption measurements through each pixel in each view of the scanner. In a preferred embodiment, detectors are identified by calculation for a pixel in every third view with detectors for intermediate views obtained by interpolation of the calculated detectors. Similarly, detectors are identified for every other pixel in a view with the detector for the intermediate pixel identified by interpolation.
摘要:
A method and apparatus for use with a gated CT imaging system for correcting for Rpeak errors in a heart beat signal, the method including identifying heart rate corresponding to each specific heart beating cycle and comparing the heart rate for each specific cycle to moving averages to determine when a likely Rpeak error has occurred and, when a likely error has occurred, modifying the heart beat signal to generate a more accurate signal and thereby render more accurate gated images.
摘要:
A procedure for use with a data acquisition system and an array processor for real time processing of the acquired data. Rather than utilize the array processor in its normal mode to process one array before moving on to the next, processing of subportions of a given array is interleaved with inputting of acquired data sets for the next array. The size of the subgroup, the number of data sets in the array, the number of channels to be processed, the nature of the process to be performed and the speed at which it can be performed are balanced in such a way that (a) processing of a subgroup is completed at about the time the next set is ready for input, and (b) at the completion of processing of the last subgroup within a given array, the last set of the next array is ready for input, so that processing of the next array commences immediately.