Patent classifications
G06T2211/408
METHOD OF PROCESSING COMPUTER TOMOGRAPHY (CT) DATA FOR FILTER BACK PROJECTION (FBP)
The present invention relates to a method of processing CT data for suppressing image cone beam artefacts (CBA) in CT images, which are reconstructed from said CT data. For the reconstruction the Frequency Split method is used. However, a straightforward use of this method can lead to an un-desired increase of the residual low-frequency noise left in the basis image after applying image domain de-noising methods. This residual noise then propagates rather linearly to the spectral results. In order to avoid this increase of the noise, the method presented here uses the FS method selectively and yet effectively. Thus, in a first aspect of the invention there is provided a method of processing computer tomography (CT) data for suppressing image cone beam artefacts (CBA) in CT images to be reconstructed from said CT data. The method comprises the steps of obtaining CT data generated during a CT scan of a patient (step S1); decomposing the obtained CT data in the projection domain resulting in a plurality of decomposed sinograms (step S2); and non-uniformly spreading between said decomposed sinograms noise and/or inconsistencies that would lead to image cone beam artefacts (step S3).
SCANNER AND METHOD OF IMAGE RECONSTRUCTION
Provided herein is technology relating to radiology and radiotherapy and particularly, but not exclusively, to apparatuses, methods, and systems for multi-axis medical imaging of patients in vertical and horizontal positions with single or dual energy acquisition.
SYSTEM AND METHOD FOR HYBRID IMAGING
The present disclosure provides systems and methods for hybrid imaging. The systems and methods may obtain a first magnetic resonance (MR) image of a target object. The first MR image may be acquired by a magnetic resonance imaging (MRI) device using a first imaging sequence. The systems and methods may also obtain a second MR image of the target object. The second MR image may be acquired by the MRI device using a second imaging sequence. The second MR image may correspond to a target respiratory phase of the target object. The systems and methods may also obtain a target emission computed tomography ECT) image of the target object. The target ECT image may correspond to the target respiratory phase. The systems and methods may further fuse, based on the second MR image, the first MR image and the target ECT image.
IMAGE DATA SEGMENTATION AND DISPLAY
A method displays spectral image data reconstructed from spectral projection data with a first reconstruction algorithm and segmented image data reconstructed from the same spectral projection data with a different reconstruction algorithm, which is different from the first reconstruction algorithm. The method includes reconstructing spectral projection data with the first reconstruction algorithm, which generates the spectral image data and displaying the spectral image data. The method further includes reconstructing the spectral projection data with the different reconstruction algorithm, which generates segmentation image data, segmenting the segmentation image data, which produces the segmented image data, and displaying the segmented image data.
Systems and methods for correcting mismatch induced by respiratory motion in positron emission tomography image reconstruction
The disclosure relates to PET imaging systems and methods. The systems may obtain a plurality of PET images of a subject and a CT image acquired by performing a spiral CT scan on the subject. Each gated PET image may include a plurality of sub-gated PET images. The CT image may include a plurality of sub-CT images each of which corresponds to one of the plurality of sub-gated PET images. The systems may determine a target motion vector field between a target physiological phase and a physiological phase of the CT image based on the plurality of sub-gated PET images and the plurality of sub-CT images. The systems may reconstruct an attenuation corrected PET image corresponding to the target physiological phase based on the target motion vector field, the CT image, and PET data used for the plurality of gated PET images reconstruction.
SPARSE BACKGROUND MEASUREMENT AND CORRECTION FOR IMPROVING IMAGING
Disclosed herein is an imaging system including a first x-ray source configured to produce first x-ray photons in a first energy range suitable for imaging, project the first x-ray photons onto an area designated for imaging, a rotatable gantry configured to rotate the first x-ray source such that the first x-ray source traverses an angular path, and a data processor having an analytical portion. The analytical portion is configured to collect first data relating to the transmission of the first x-ray photons through the area designated for imaging at a set of image-collection angles along the angular path, collect background data at a set of background-collection angles along the angular path, wherein the system acquires more than one image of the designated area for imaging between background angles. The analytical portion is also configured to remove errors in the first data using the background data, and generate a corrected image based on the removal of errors in the first data.
SYSTEM AND METHOD FOR QUANTITATIVE BLOOD VOLUME IMAGING
A system and method for generating reports on perfusion blood volume from computed tomography (CT) data acquired from a subject. The method includes receiving multi-faceted CT data acquired from the subject using one of a multi-energy or polychromatic CT acquisition and deriving an iodine concentration in an artery feeding a volume of interest (VOI) in the multi-faceted CT data. The method further includes determining an effective atomic number of a spatial distribution in the VOL calculating a perfused blood volume of the VOI using the iodine concentration and the effective atomic number, and generating a report of the perfused blood volume of the VOI.
SYSTEMS AND METHODS FOR CORRECTING MISMATCH INDUCED BY RESPIRATORY MOTION IN POSITRON EMISSION TOMOGRAPHY IMAGE RECONSTRUCTION
The disclosure relates to PET imaging systems and methods. The systems may obtain a plurality of PET images of a subject and a CT image acquired by performing a spiral CT scan on the subject. Each gated PET image may include a plurality of sub-gated PET images. The CT image may include a plurality of sub-CT images each of which corresponds to one of the plurality of sub-gated PET images. The systems may determine a target motion vector field between a target physiological phase and a physiological phase of the CT image based on the plurality of sub-gated PET images and the plurality of sub-CT images. The systems may reconstruct an attenuation corrected PET image corresponding to the target physiological phase based on the target motion vector field, the CT image, and PET data used for the plurality of gated PET images reconstruction.
System and method for basis material decomposition with general physical constraint for multi-energy computed tomography
A system and method is provided for performing material decomposition using a computed tomography (CT) system. The method includes acquiring CT imaging data of an object including data subsets corresponding to at least two different energy spectral bins and using the CT imaging data at each of the at least two different energy spectral bins to form a series of equations for basis material decomposition. The method also includes using a general physical constraint, which quantifies how each basis material in the object is mixed together to form the object, within the series of equations. The method also includes determining at least one basis material density of the object using the physical constraint and the CT imaging data and generating an image of the object using the CT imaging data and the mass densities of at least one basis material.
IMAGE PROCESSING APPARATUS, IMAGE PROCESSING METHOD, AND STORAGE MEDIUM
An image processing apparatus that processes a radiation image generates a decomposition image representing a planar distribution related to a material, using a plurality of radiation images of an object containing a target object that correspond to different radiation energies, and obtains a target object image related to the target object using a band limitation image corresponding to a frequency band related to a size of the target object, the band limitation image being obtained by performing frequency decomposition on the decomposition image.