Abstract: A method of processing radiation from a source is described comprising: positioning a detector to receive radiation from the source; positioning a collimator between the source and the detector, wherein the collimator has a plurality of apertures; allowing radiation from the source to pass through the collimator and be incident upon the detector; receiving a plurality of responses each being a response to an interaction with incident radiation occurring within the detector; determining, for each of the plurality of responses, a characteristic of the interaction, wherein the characteristic comprises at least a position and depth of the interaction within the detector; processing the said plurality of responses by simultaneously processing position and depth of interaction data in such manner as to accommodate the effect of multiplexing due to overlap of the projected radiation pathways from multiple apertures in the collimator at the detector on the detected position on the detector.

Abstract: A method includes receiving Emission Tomography (ET) data of a subject from an ET/Computed Tomography (CT) scanner. The method further includes generating a first motion signal corresponding to a first bed position of the ET/CT scanner from the received ET data and determining whether the first motion signal indicates a periodic motion. The method also includes calculating a first time period from the first motion signal in response to determining that the first motion signal indicates the periodic motion and sending a first acquire notification to the ET/CT scanner to acquire Cinematographic (CINE) Computed Tomography (CT) data from the first bed position based on the first time period.

Abstract: Methods and systems for processing a set of images are described. In accordance with this disclosure, images are registered and an analysis is performed in view of one or more constraints (such as constraints based upon anatomical or physiological considerations). Weighting factors are determined based on the analysis. The weighting factors are used in subsequent processing of the registered (and/or unregistered) images and/or to formulate a visualization that conveys the degree of confidence in the motion estimation used in the registration process.

Abstract: A method implemented using at least one processor includes receiving time-varying image dataset generated by a medical imaging modality. The image dataset corresponds to a bed position and is affected by quasi-periodic motion data. The method also includes applying a signal decomposition technique to the time-varying image dataset to generate a plurality of dataset components and a plurality of motion signals. The method also includes determining reference data based on the time-varying image dataset, wherein the reference data is representative of a direction of the quasi-periodic motion. The method further includes deriving polarity of each of the plurality of motion signals based on the reference data to generate a plurality of sign corrected motion signals. The method also includes determining a gating signal corresponding to the bed position based on at least one of the plurality of sign corrected motion signals.

Abstract: A method implemented using at least one processor includes receiving time-varying image dataset generated by a medical imaging modality. The image dataset corresponds to a bed position and is affected by quasi-periodic motion data. The method also includes applying a signal decomposition technique to the time-varying image dataset to generate a plurality of dataset components and a plurality of motion signals. The method also includes determining reference data based on the time-varying image dataset, wherein the reference data is representative of a direction of the quasi-periodic motion. The method further includes deriving polarity of each of the plurality of motion signals based on the reference data to generate a plurality of sign corrected motion signals. The method also includes determining a gating signal corresponding to the bed position based on at least one of the plurality of sign corrected motion signals.

Abstract: A method includes receiving Emission Tomography (ET) data of a subject from an ET/Computed Tomography (CT) scanner. The method further includes generating a first motion signal corresponding to a first bed position of the ET/CT scanner from the received ET data and determining whether the first motion signal indicates a periodic motion. The method also includes calculating a first time period from the first motion signal in response to determining that the first motion signal indicates the periodic motion and sending a first acquire notification to the ET/CT scanner to acquire Cinematographic (CINE) Computed Tomography (CT) data from the first bed position based on the first time period.

Abstract: Methods and systems for processing a set of images are described. In accordance with this disclosure, images are registered and an analysis is performed in view of one or more constraints (such as constraints based upon anatomical or physiological considerations). Weighting factors are determined based on the analysis. The weighting factors are used in subsequent processing of the registered (and/or unregistered) images and/or to formulate a visualization that conveys the degree of confidence in the motion estimation used in the registration process.

Abstract: Methods and systems for processing a set of images are described. In accordance with this disclosure, images are registered and an analysis is performed in view of one or more constraints (such as constraints based upon anatomical or physiological considerations). Weighting factors are determined based on the analysis. The weighting factors are used in subsequent processing of the registered (and/or unregistered) images and/or to formulate a visualization that conveys the degree of confidence in the motion estimation used in the registration process.

Abstract: A method and apparatus are provided for reducing motion related imaging artifacts. The method includes obtaining an image data set of a region of interest in an object, obtaining a motion signal indicative of motion of the region of interest, determining at least one quiescent period of at least a portion of the motion signal, extracting image data from the image data set that is within the determined quiescent period to form an image data subset, and generating an image of the region of interest using the image data subset.

Abstract: A method for reducing, in an image, motion related imaging artifacts includes obtaining an image dataset of a region of interest, generating a plurality of intermediate images using the image dataset, applying a multivariate data analysis technique to the plurality of the intermediate images to generate motion information, sorting the intermediate images into a plurality of bins based on the motion information, and generating an image of the region of interest using at least one of the plurality of bins.

Abstract: Methods and systems for multiple scatter estimation in Positron Emission Tomography (PET) are provided. One method includes determining attenuation sinograms and determining a varying convolution kernel as a function of the attenuation sinograms, wherein the kernel varies in amplitude and width over a radial length of a PET imaging system. The method also includes using the varying convolution kernel to estimate multiple PET scatter.

Abstract: A method for generating an image is provided. The method comprises: acquiring a first set of image data using a first imaging modality; sorting the first set of image data into a plurality of gates to generate a plurality of gated data sets; reconstructing each gated data set to generate a respective gated image for each gated data set; registering the respective gated images to generate a plurality of registered images; and generating a median image from the plurality of registered images, wherein each voxel of the median image is a respective median value of the corresponding voxels of the plurality of registered images.

Abstract: A method and apparatus are provided for reducing motion related imaging artifacts. The method includes obtaining an image data set of a region of interest in an object, obtaining a motion signal indicative of motion of the region of interest, and determining a displacement and a phase of at least a portion of the motion signal. The method also includes mapping the image data set into a matrix based on the displacement and phase of the motion signal, and generating an image of the region of interest from the matrix.

Abstract: An imaging method comprises reconstructing gated emission tomography images for a region of interest, adjusting a mismatch between the gated emission tomography images and a computed tomography image of the region of interest, registering the gated emission tomography images, and combining the registered gated emission tomography images to generate motion corrected images.

Abstract: Methods and systems for multiple scatter estimation in Positron Emission Tomography (PET) are provided. One method includes determining attenuation sinograms and determining a varying convolution kernel as a function of the attenuation sinograms, wherein the kernel varies in amplitude and width over a radial length of a PET imaging system. The method also includes using the varying convolution kernel to estimate multiple PET scatter.

Abstract: A method and apparatus are provided for reducing motion related imaging artifacts. The method includes determining an internal motion for of two regions of the object, each region having a different level of motion, scanning the first region using a first scan protocol based on the motion, scanning a second region using a second different scan protocol based on the motion, and generating an image of the object based on the first and second regions.

Abstract: A method for generating an image is provided. The method comprises: acquiring a first set of image data using a first imaging modality; sorting the first set of image data into a plurality of gates to generate a plurality of gated data sets; reconstructing each gated data set to generate a respective gated image for each gated data set; registering the respective gated images to generate a plurality of registered images; and generating a median image from the plurality of registered images, wherein each voxel of the median image is a respective median value of the corresponding voxels of the plurality of registered images.

Abstract: A method for reducing, in an image, motion related imaging artifacts includes obtaining an image dataset of a region of interest, generating a plurality of intermediate images using the image dataset, applying a multivariate data analysis technique to the plurality of the intermediate images to generate motion information, sorting the intermediate images into a plurality of bins based on the motion information, and generating an image of the region of interest using at least one of the plurality of bins.

Abstract: Methods and systems for processing a set of images are described. In accordance with this disclosure, images are registered and an analysis is performed in view of one or more constraints (such as constraints based upon anatomical or physiological considerations). Weighting factors are determined based on the analysis. The weighting factors are used in subsequent processing of the registered (and/or unregistered) images and/or to formulate a visualization that conveys the degree of confidence in the motion estimation used in the registration process.

Abstract: A method and apparatus are provided for reducing motion related imaging artifacts. The method includes obtaining an image data set of a region of interest in an object, obtaining a motion signal indicative of motion of the region of interest, determining at least one quiescent period of at least a portion of the motion signal, extracting image data from the image data set that is within the determined quiescent period to form an image data subset, and generating an image of the region of interest using the image data subset.