Abstract:
A method and system for calibrating a time of flight (TOF) positron emission tomography (PET) scanner are provided. The method stores acquired scan data from detector pairs including data and timing information. The method further calculates an intensity distribution of emission sources based on the scan data and defines a timing pivot point based on a median of an intensity histogram. The method determines a timing correction for each detector based on the location of the timing pivot point. The positron emission tomography (PET) system further provides a plurality of detectors, used in performing imaging scans, and a processor. The processor is configured to determine a timing correction for each detector.
Abstract:
A region of interest is automatically evaluated. The automatic evaluation is based on assessments of one or more characteristics. The one or more characteristics of the region of interest are assessed in a plurality of image data sets acquired by a respective plurality of imaging modalities. In some embodiments, the evaluation is based on assessments of one or more characteristics for each region of interest derived from a combination of structural and functional image data. In one embodiment, the set of structural image data is a set of CT image data and the set of functional image data is a set of PET image data. The one or more lesions may be detected in the structural and/or functional image data by automated routines or by a visual inspection by a clinician or other reviewer.
Abstract:
The invention is directed to a technique for reconstructing PET scan images. According to one embodiment, the invention relates to a method for reconstructing PET scan images. The method comprises: detecting a plurality of coincidence events in a PET scanner; storing data associated with the plurality of coincidence events in a chronological list based on a detection time for each of the plurality of coincidence events; generating correction data based on scatter coincidence events and random coincidence events in the plurality of coincidence events; and reconstructing one or more PET scan images based at least in part on the chronological list of data and the correction data.
Abstract:
A Nuclear Medicine (NM) imaging system and method using multiple types of imaging detectors are provided. One NM imaging system includes a gantry, at least a first imaging detector coupled to the gantry, wherein the first imaging detector is a non-moving detector, and at least a second imaging detector coupled to the gantry, wherein the second imaging detector is a moving detector. The first imaging detector is larger than the second imaging detector and the first and second imaging detectors have different detector configurations. The NM imaging system further includes a controller configured to control the operation of the first and second imaging detectors during an imaging scan of an object to acquire Single Photon Emission Computed Tomography (SPECT) image information such that at least the first imaging detector remains stationary with respect to the gantry during image acquisition.
Abstract:
A Nuclear Medicine (NM) imaging system and method using multiple types of imaging detectors are provided. One NM imaging system includes a gantry, at least a first imaging detector coupled to the gantry, wherein the first imaging detector is a non-moving detector, and at least a second imaging detector coupled to the gantry, wherein the second imaging detector is a moving detector. The first imaging detector is larger than the second imaging detector and the first and second imaging detectors have different detector configurations. The NM imaging system further includes a controller configured to control the operation of the first and second imaging detectors during an imaging scan of an object to acquire Single Photon Emission Computed Tomography (SPECT) image information such that at least the first imaging detector remains stationary with respect to the gantry during image acquisition.
Abstract:
A method for determining the effectiveness of an image transformation process includes acquiring a four-dimensional (4D) image data set, sorting the 4D image data set into separate field-of-view bins using a temporal gating system generating a plurality of deformation vectors using the sorted 4D image data set, and using the plurality of deformation vectors to generate a transformation effectiveness value that is representative of the effectiveness of the image transformation process. The method further includes acquiring a respiratory signal, calculating a power spectrum of the respiratory signal, calculating a power spectrum for each of the plurality of deformation vectors, and comparing the power spectrum of the respiratory signal to the power spectrum of the plurality of deformation vectors to generate the transformation effectiveness value.
Abstract:
A method for determining the effectiveness of an image transformation process includes acquiring a four-dimensional (4D) image data set, sorting the 4D image data set into separate field-of-view bins using a temporal gating system generating a plurality of deformation vectors using the sorted 4D image data set, and using the plurality of deformation vectors to generate a transformation effectiveness value that is representative of the effectiveness of the image transformation process. The method further includes acquiring a respiratory signal, calculating a power spectrum of the respiratory signal, calculating a power spectrum for each of the plurality of deformation vectors, and comparing the power spectrum of the respiratory signal to the power spectrum of the plurality of deformation vectors to generate the transformation effectiveness value.
Abstract:
Methods and systems for imaging by using a filter for Time-Of-Flight Positron Emission Tomography (TOF PET) are described. The described methods of imaging a patient by using a positron emission tomography (PET) system includes acquiring a plurality of frames of sinogram data, filtering the acquired sinogram data and back-projecting the filtered sinogram data to form an output image of the patient. The acquired sinogram data defines a line of response (LOR) and a time-of-flight (TOF) measurement that localizes positron annihilation within the patient. The filtering of the acquired sinogram data is performed using the TOF measurement.
Abstract:
Systems and methods for attenuation compensation in nuclear medicine imaging based on emission data are provided. One method includes acquiring emission data at a plurality of energy windows for a person having administered thereto a radiopharmaceutical comprising at least one radioactive isotope. The method also includes performing a preliminary reconstruction of the acquired emission data to create one or more preliminary images of a peak energy window and a scatter energy window and determining a body outline of the person from at least one of the reconstructed preliminary image of the peak energy window or of the scatter energy window. The method further includes identifying a heart contour and segmenting at least the left lung. The method additionally includes defining an attenuation map based on the body outline and segmented left lung and reconstructing an image of a region of interest of the person using an iterative joint estimation reconstruction.
Abstract:
A method and system for reconstructing an image in a time-of-flight (TOF) positron emission tomography (PET) system is provided. The method includes using a reconstructed image to determine predicted timing information. Timing bias data is updated based on received timing information associated with acquired scan data from a PET system and the predicted timing information. The method further includes reconstructing the image, based on the updated timing bias data.